Hello friends, I hope you all are doing great. Today, I am going to share the Raspberry Pi 4 Library for Proteus. In our previous tutorial, we shared the Raspberry Pi 3 Library for Proteus and as we mentioned in that tutorial, these Raspberry Pi libraries will have dummy modules i.e. We have just designed the exterior but these boards won't be able to read the Python code. Although just for fun, we have added the Arduino firmware in these boards, so we can upload the Arduino code in it. As the legends say, something is better than nothing. We have given these boards an unofficial name "Arduino Pi".
You can use these Pi boards to design your circuit diagram or can also use it in your presentation/demonstration of your projects. I hope you will enjoy these simulated Raspberry Pi boards. Before going forward, let's first have a brief overview of Raspberry Pi 4:
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Battery 12V | Amazon | Buy Now | |
| 2 | LEDs | Amazon | Buy Now | |
| 3 | Resistor | Amazon | Buy Now | |
| 4 | Raspberry Pi 4 | Amazon | Buy Now | |
So, now let's have a look at How to add this Proteus library and simulate Raspberry Pi 4 in Proteus.
Raspberry Pi 4 Library for Proteus
Now let's design the Simulation of Raspberry Pi 4 in Proteus. As I mentioned earlier, we can't feed Python code to this RPi4 board. So, we have added the Arduino firmware to it. Thus, we need to upload the Arduino hex file in it. Let's attach an LED with Raspberry Pi 4:
So, that was all for today. I hope you will enjoy this Raspberry Pi 4 Library for Proteus and will use it in your projects. Let me know your feedback. Have a good day. Take care!!!
Thank you for joining us today for our in-depth Raspberry Pi programming tutorial. The previous guide covered the steps necessary to connect a fingerprint scanner to a Raspberry Pi 4. In addition, we developed a python script to complement the sensor's ability to identify fingerprints. Yet, in this guide, we'll discover how to interface a ws2812 RGB to a Raspberry Pi 4.
Bright, colorful lights are the best, and this tutorial shows you how to set up Fully Configurable WS2812B led strips to run on a Pi 4 computer as quickly and flexibly as possible. In that manner, you can have the ambiance of your home reflect your tastes.
In most cases, when people talk about a "WS2812B Strip," they mean a long piece of extensible PCB with a bunch of different RGB LED Nodes spread out and dotting all along the top. As a bonus, WS2812B strips can be addressed individually. Each RGB node can independently set its own color and brightness. The functionality of non-addressable RGB strips will be identical to that of WS2812B strips. WS2812B Strips are superior in every way, allowing for more imaginative LED light shows. It is possible to create more complex animations, stripes, and chases by individually programming the actions of each LED Node.
The "WS" in WS2812B indicates that this is the second major revision of this design; "World Semi" refers to the chip's original equipment manufacturer, "2812" to its specific part number, and "B" to its revision number. Each WS2812B LED Node contains an integrated circuit chip, as shown below.
Fully Configurable Strip LEDs now come in wide varieties. It's important to remember whether the strip operates on 5 volts or 12-volt power. To power our 5V-powered Raspberry Pi Computer, we need to use a 5V power supply. Or we'll have to install extra gear to meet the 12v Dc power specifications. LED Node densities also vary across WS2812B LED strips. Since our strip consists of WS2812B nodes soldered onto rigid PCBs, it may also be controlled by the Python script included in this article. ws2812B LED strips are the ideal LEDs to use because of the benefits above. What this manual entails is listed below.
The control mechanism implemented in this tutorial works with WS2812B LED nodes, whether they are rigidly coupled on a PCB or flexibly arranged over a long strip. No prior experience with Raspberry Pi has required, thanks to our comprehensive online raspberry pi 4 for the introduction. You should be able to follow these guidelines if you've read at least chapter 1.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Jumper Wires | Amazon | Buy Now | |
| 2 | Raspberry Pi 4 | Amazon | Buy Now | |
Let's go over the protocol for these addressable LEDs so you can see how they function. Each WS2812B unit's red, green, and blue LEDs can be independently controlled to one of 256 brightness levels. Each LED module needs 24 bits of data or three groups of eight brightness bits. Here's a quick rundown of the steps involved:
The first LED in the string receives this data stream from the microcontroller, which consists of eight green bits, eight red bits, and eight blue bits.
In the case of several LEDs, the data sequence for the second LED begins with green, red, and blue information immediately after the information for the first LED. The process repeats itself until each LED is turned on.
The first LED acts as a receiver for data for all subsequent LEDs in the chain and then sends that data to the second LED without applying the same sequence.
When the original "number one" LED unit runs out of binary LED sequences, it passes the baton to the next available unit.
What follows are detailed instructions for configuring a single Raspberry Pi board to manage many individually addressable LEDs.
A pi 4
5v led strip
A DC barrel jack to 2-pin terminal block adapter.
More than 30 WS2812B strip Nodes will necessitate the usage of an external power supply. Even with highly efficient LEDs, producing brilliant light takes a lot of energy. On average, each pixel will consume 20mA, and while projecting white light at full brightness, each pixel will consume 60mA. This information shows us that 30 Pixels can consume 600mA on average and 1.8A at full brightness. As a side note, staring directly into a room with the lights set to full white causes blind spots in my vision. Because of this, I typically set the brightness of my WS2812B lights to 20%. Ensure your WS2812B strip's power source is adequate for the illumination level you intend to achieve.
In today's world, 3.3V data logic is compatible with most WS2812B LED nodes. The GPIO Pins on a Raspberry Pi have an operational voltage range of 0 to 3.3V; therefore, this works out perfectly. This surface-mounted WS2812B strip Node has seen five minor changes since its inception. Since the earlier WS2812B strip can only work on 5V Data Logic, a logical level shifter may be necessary if you're experiencing strange or intermittent issues.
We'll configure our Raspberry PI to look and act like a desktop PC because that's how most people use computers at home and because it's the most user-friendly setup for novice makers. To convert our Raspberry Pi into a desktop computer, we'll need to install a micro-SD card pre-flashed with the operating system. Then hook it up to a monitor via HDMI and a mouse/keyboard combo. Also, this is a good moment to install a small heatsink on the Raspberry Pi Board's central processing unit IC. Look at the image below to see the setup adjacent to a short WS2812B LED strip with three wires protruding from it. The WS2812B has three wires that have not yet been connected to the Raspberry Pi. WS2812B LED Strip PCBs are often marked with arrows to indicate the direction of data flow. It is a common problem in troubleshooting when this is ignored.
How to Configure Hardware for WS2812B Chains with fewer than 30 Nodes We need to plug in the 5V WS2812B Strip's three wires to the Raspberry Pi before turning the power on. Link the Raspberry Pi's 5V Power Input Pin with the Red Power Cable. Join the white wire labeled "Ground" to the Pi's Ground pin. Join the Raspberry Pi's Green Input Pin to its GPIO 18 port. It is important to remember that the Green Input Pin could be any GPIO pin as long as the appropriate adjustments are made in your Python programs. In this manual, GPIO 18 will be used for the Data Line in all scripts. The picture below shows how these three wires are joined together. This straightforward system can provide power and data transmission for a limited amount of LEDs.
Hardware Configuration for a WS2812B Strip with more than 30 Nodes in Length. However, the Pi 4 Power Pin Out is not powerful enough to power a full LED strip. It's important to know the power requirements of fully addressable WS2812B LEDs, especially when used in large quantities. 150 fully illuminated RGBW LEDs should be manageable by a high-quality 5v 4A power supply.
Following the diagram below, we will connect a 5V 4A power source via a DC barrel jack. Our WS2812B LEDs are pre-soldered with one green data wire, two red power wires, and two white ground wires. The white wire should be attached to the DC barrel jack's negative terminal using a screwdriver. Join the Red Wire to the Terminal With the Positive Screw Down. The White Connectors all link to one other, indicating a Common Ground shared by the Raspberry Pi and the power source. The two devices can't be connected without ground, which will prevent voltage fluctuations and data transmission mistakes.
Furthermore, the WS2812B Strip is no longer connected to the Pi 4 computer via a red power wire. We have found an alternative to using a Raspberry Pi to run our system. See the diagram below for details on connecting a Raspberry Pi to a string of WS2812B LEDs so that they may be controlled remotely.
There are several great best practices to keep in mind if you're planning on powering many LED strips. If you need to run more than a 5-meter roll of LEDs, I recommend consulting the adafruit documentation on the subject. It's important to think about heat and currents.
Now that everything is hooked up how you like it, you can turn on the Pi 4 System by inserting a USB-C cable.
You'll need to install a few packages if you're starting with a clean install of Raspberry Pi OS. Since this is the case, WS2812B LEDs will function properly. When you plug the Raspberry Pi into an electrical outlet and finish the initial boot-up wizard, you will be taken to the operating system's familiar desktop.
Click the black button in the upper left corner to open a new terminal window. An interactive terminal will launch. Below is a picture of this happening, with a huge red arrow indicating the pressed terminal icon.
With this terminal window, we can search for specific programs and download them from the internet. Here are the command lines you use in the terminal to install everything you need. Type | Y | to confirm installs if prompted.
sudo pip3 install rpi_ws281x
sudo pip3 install adafruit-circuitpython-neopixel
sudo python3 -m pip install --force-reinstall adafruit-blinka
You now have the software and programming packages installed on your Device to power and run WS2812B properly.
You may trigger the Raspberry Pi to turn on the associated WS2812B LED strips in various ways. To begin, I will utilize the simplest and quickest technique, which involves hooking up this Raspberry Pi to a monitor, mouse, and keyboard so that I can execute Python scripts directly to control it. Below, you'll find the best and most fun Python script to start with: | strandtest.py |. Even though it's far more involved than the rest of the Python scripts in this tutorial, we felt it was essential to include it first because it provides a comprehensive overview of the various possible patterns and lighting styles.
import time
from rpi_ws281x import *
import argparse
LED_COUNT = 30
LED_PIN = 18
LED_FREQ_HZ = 800000 # LED signal frequency in hertz (usually 800khz)
LED_DMA = 10 # DMA channel to use for generating a signal (try 10)
LED_BRIGHTNESS = 65 # Set to 0 for darkest and 255 for brightest
LED_INVERT = False # True to invert the signal (when using NPN transistor level shift)
LED_CHANNEL = 0 # set to '1' for GPIOs 13, 19, 41, 45 or 53
def colorWipe(strip, color, wait_ms=50):
"""Wipe color across display a pixel at a time."""
for i in range(strip.numPixels()):
strip.setPixelColor(i, color)
strip.show()
time.sleep(wait_ms/1000.0)
def theaterChase(strip, color, wait_ms=50, iterations=10):
"""Movie theater light style chaser animation."""
for j in range(iterations):
for q in range(3):
for i in range(0, strip.numPixels(), 3):
strip.setPixelColor(i+q, color)
strip.show()
time.sleep(wait_ms/1000.0)
for i in range(0, strip.numPixels(), 3):
strip.setPixelColor(i+q, 0)
def wheel(pos):
"""Generate rainbow colors across 0-255 positions."""
if pos < 85:
return Color(pos * 3, 255 - pos * 3, 0)
elif pos < 170:
pos -= 85
return Color(255 - pos * 3, 0, pos * 3)
else:
pos -= 170
return Color(0, pos * 3, 255 - pos * 3)
def rainbow(strip, wait_ms=20, iterations=1):
"""Draw rainbow that fades across all pixels at once."""
for j in range(256*iterations):
for i in range(strip.numPixels()):
strip.setPixelColor(i, wheel((i+j) & 255))
strip.show()
time.sleep(wait_ms/1000.0)
def rainbowCycle(strip, wait_ms=20, iterations=5):
"""Draw rainbow that uniformly distributes itself across all pixels."""
for j in range(256*iterations):
for i in range(strip.numPixels()):
strip.setPixelColor(i, wheel((int(i * 256 / strip.numPixels()) + j) & 255))
strip.show()
time.sleep(wait_ms/1000.0)
def theaterChaseRainbow(strip, wait_ms=50):
"""Rainbow movie theater light style chaser animation."""
for j in range(256):
for q in range(3):
for i in range(0, strip.numPixels(), 3):
strip.setPixelColor(i+q, wheel((i+j) % 255))
strip.show()
time.sleep(wait_ms/1000.0)
for i in range(0, strip.numPixels(), 3):
strip.setPixelColor(i+q, 0)
# Main program logic follows:
if __name__ == '__main__':
# Process arguments
parser = argparse.ArgumentParser()
parser.add_argument('-c', '--clear', action='store_true', help='clear the display on exit')
args = parser.parse_args()
# Create NeoPixel object with appropriate configuration.
strip = Adafruit_NeoPixel(LED_COUNT, LED_PIN, LED_FREQ_HZ, LED_DMA, LED_INVERT, LED_BRIGHTNESS, LED_CHANNEL)
# Intialize the library (must be called once before other functions).
strip.begin()
print ('Press Ctrl-C to quit.')
if not args.clear:
print('Use "-c" argument to clear LEDs on exit')
try:
while True:
print ('Color wipe animations.')
colorWipe(strip, Color(255, 0, 0)) # Red wipe
colorWipe(strip, Color(0, 255, 0)) # Blue wipe
colorWipe(strip, Color(0, 0, 255)) # Green wipe
print ('Theater chase animations.')
theaterChase(strip, Color(127, 127, 127)) # White theater chase
theaterChase(strip, Color(127, 0, 0)) # Red theater chase
theaterChase(strip, Color( 0, 0, 127)) # Blue theater chase
print ('Rainbow animations.')
rainbow(strip)
rainbowCycle(strip)
theaterChaseRainbow(strip)
except KeyboardInterrupt:
if args.clear:
colorWipe(strip, Color(0,0,0), 10)
Get started with Python using an IDE like Thonny IDE. You can use any Python Interpreter you like, as Thonny IDE is one of many. Thonny IDE can be accessed through the Application Menu under the Programming submenu. Then, copy the above code inside Thonny Python Editor and save it as strandtest.py on your desktop. Proceed by clicking the large green Run button. See what happens when you do that in the image below.
With that, you should see vibrant hues coming from your LED strip. If individual LEDs on your WS2812B LED Strip aren't lighting up, but the others are, open the Python script, locate the variable labeled LED COUNT, and raise its value till it's in line with the number of LEDs on your strip. The script can be saved and re-run by clicking the Run button. To accommodate the enormous quantity of WS2812B LED Strip, I set this variable to 150. In the next image, you can see a long WS2812B strip that has been wired to an external power source and is controlled by the modified Python script.
Now you can check if your Device is properly constructed and functioning with the help of the above strandtest.py script. Moreover, the resulting illumination is just breathtaking. Maker may be left wanting more, though. This is of special importance to the readability of the code, which facilitates its adaptation to specific tasks. This section will show you how to control the WS2812B strip with a few basic Python programs easily modified to suit your needs.
To get started, look at OneStripNeopixels.py, a very basic WS2812B Control Script.
import time
import board
import neopixel
#Initialise, a strips variable, provide the GPIO Data Pin
# utilized and the amount of LED Nodes on the strip and brightness (0 to 1 value)
pixels1 = neopixel.NeoPixel(board.D18, 55, brightness=1)
#Also, create an arbitrary count variable
x=0
pixels1.fill((0, 220, 0))
#LED Node 10 and the color Blue were selected
pixels1[10] = (0, 20, 255)
#Showing a different color
time.sleep(4)
#Below will loop until variable x has a value of 35
while x<35:
pixels1[x] = (255, 0, 0)
pixels1[x-5] = (255, 0, 100)
pixels1[x-10] = (0, 0, 255)
#Add 1 to the counter
x=x+1
#Add a small time pause which will translate to 'smoothly' changing color
time.sleep(0.05)
#Below section is the same process as the above loop, just in reverse
while x>-15:
pixels1[x] = (255, 0, 0)
pixels1[x+5] = (255, 0, 100)
pixels1[x+10] = (0, 255, 0)
x=x-1
time.sleep(0.05)
#Add a brief time delay to appreciate what has happened
time.sleep(4)
#Complete the script by returning all the LEDs to the off
pixels1.fill((0, 0, 0))
The Python script has been thoroughly commented on, so you should have no trouble following along. The script in the previous paragraph includes readily apparent dials and switches. You'll learn the fundamentals of making a captivating LED Pattern, including how to adjust the number of LED Nodes, the brightness of the LED strips, whether to illuminate the entire board or just a section of it and how to illuminate individual LEDs. Each Node color can be customized by entering a corresponding Red, Blue, or Green numeric value. A number can have any value between zero and 255. The term "RGB Color Code" is commonly used to describe this. While experimenting with different hues can be a lot of fun, the best method to find the precise shade you need is to use a website that lists RGB color codes. Choose any color on this site, and you'll get its corresponding RGB color code in three numbers. After you've located the three-digit color code, you can easily enter it into the Python program.
You can copy and paste the script into Thonny IDE and run it. Once you've saved the file, you can press the run button to activate the script. Below are some screenshots displaying the output.
Next is to hook up a few different LED Strips to the Pi 4 SBC and run a Python script to manage everything. Hardware-wise, I've replicated the procedure described in Hardware Configuration for Small, fewer than 30 Nodes long WS2812B, adding a second, similarly-sized WS2812B LED Strip.
I wired an additional WS2812B strip of lights up to the GPIO in the manner described below. The Raspberry Pi's other 5V Pin was connected to the red power line. The Raspberry Pi's White Ground Wire was attached to the board's second Ground Port. In this case, GPIO 21 received the green data wire. Check out the diagram of the wired components below; using two WS2812B LED strips of varying density is fine.
Using Thonny IDE as previously, run the python script titled TwoStripsNeopixels.py to control these two WS2812B Strips in a no-frills fashion. Look at this thoroughly documented Python script down here.
#include all necessary packages to get LEDs to work with Raspberry Pi
import time
import board
import neopixel
#Initialise two strips variables, provide the GPIO Data Pin
# utilized and the amount of LED Nodes and brightness (0 to 1 value)
pixels1 = neopixel.NeoPixel(board.D18, 30, brightness=1)
pixels2 = neopixel.NeoPixel(board.D21, 6, brightness=1)
#Focusing on a particular strip, use the command Fill to make it all a single color
#based on decimal code R, G, B. Number can be anything from 255 - 0. Use an RGB Colour
#Code Chart Website to quickly identify a desired fill color.
pixels1.fill((0, 255, 0))
pixels2.fill((0, 0, 255))
#Sleep for one second, and then code repeats for different color combinations. Light changes
#Could happen instead in response to certain buttons being pressed or due to threshold values
time.sleep(1.5)
pixels1.fill((200, 200, 0))
pixels2.fill((0, 200, 200))
time.sleep(1.5)
pixels1.fill((50, 70, 215))
pixels2.fill((215, 50, 70))
time.sleep(1.5)
pixels1.fill((0, 0, 0))
pixels2.fill((0, 0, 0))
Note that a Pi 4Computer has four Data Wire locations that can control individual WS2812B LED Strips, provided the corresponding Python script is updated correctly. The pinouts are numbered as follows: GPIO18, GPIO21, GPIO12, and GPIO10. With some tweaking and development of this technique, you can use a single Raspberry Pi as a standalone controller for four individually addressable WS2812B strips.
Ensure the right number of LED Nodes has been assigned to both LED WS2812B Strips before running the script. Once the script is ready to be executed, click the Thonny IDE's large green Run button. Both strands will suddenly come to life, each filled with a unique color. In the picture below, you can see this in action.
In this tutorial, we looked at connecting a WS2812B led strip to a Raspberry Pi. We also programmed the LEDs to blink in various patterns and colors using Python. You may now explore with your raspberry pi and these led strips to create patterns or whatever you like. Next, we'll look at connecting a Pi 4 to a sharp infrared distance measurement sensor.
Welcome to today's article on our comprehensive Raspberry Pi 4 programming guide. As we saw in the previous article, the Raspberry Pi 4 may power a single seven-segment display. In addition, we also interfaced a Raspberry Pi with 4 Seven-Segment Display Modules to display the time. However, this guide will show you how to construct a Raspberry Pi 4 crypto miner that uses very little electricity.
Cryptocurrencies have been the subject of widespread conversation for some time now. It's possible to use your computer to create them, and they can be used as currency. Because of this, the Raspberry Pi can also be used for Bitcoin mining. It's also possible to mine other cryptocurrencies. One drawback of mining is that the cost of electricity often exceeds the revenue it brings in. So, let's check out how to construct a solar-powered, money-making cryptocurrency miner with a Raspberry Pi.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Raspberry Pi 4 | Amazon | Buy Now | |
A pool account
Bitcoin Wallet
Raspberry Pi
Raspbian image SD card
USB Bitcoin miner
Crypto mining, the digital equivalent of the gold mining industry, involves a combination of complex mathematical calculations and blind luck. Mining is crucial for cryptocurrencies as it is the only way to update the distributed ledger (Blockchain).
Despite Bitcoin's popularity, there are other digital currencies available. All cryptocurrencies use blockchains to ensure that all transactions are legitimate and that users cannot spend the same cryptocurrency more than once.
To simplify things for the unfamiliar in the web3 environment, let's say that a blockchain is a distributed ledger that maintains track of all transactions made over it. Similar to how a bank keeps a record of who gave money to whom, how much was sent, and when it was sent, blockchain stores this unchangeable data within distributed blocks linked together via a network.
Users, known as miners or validator nodes, provide the network's computational power to verify all of the blockchain's transactions. This blog post will not delve further into smart contracts, which are computer programs that can be set up to run automatically on a blockchain if and only if specific criteria are met.
Bitcoin and Ethereum miners are sometimes pictured as a large server farm full of powerful graphics processing unit (GPU) or application-specific integrated circuit (ASIC) devices that work tirelessly to solve complex cryptographic puzzles issued by the blockchain in exchange for financial rewards. The consensus technique for validating submissions and awarding incentives varies from blockchain to blockchain.
Raspberry Pi users can choose from several different coins to mine, but not all are profitable. The most profitable option is the one you should choose. The USB miner is crucial to mining since it dramatically boosts productivity. In mining, you have two primary options:
For anyone interested in beginning mining using a USB miner like NEWPAC, selecting a cryptocurrency that uses the SHA-256 algorithm is a must. Bitcoin (BTC), Bitcoin Cash (BCH), Bitcoin SV (BSV), and many others are just some of the cryptocurrencies that use the SHA-256 algorithm. However, Bitcoin is the most lucrative and should be explored first if you plan to mine using a Raspberry Pi.
The Raspberry Pi's central processing unit (CPU) can be used to begin mining in the absence of a dedicated USB miner. In such a scenario, you should go with Monero (XMR), the coin that can be mined with the least effort using a Raspberry Pi.
After calculating electricity and equipment costs, I found that bitcoin mining with a regular computer could have been more worthwhile. Most bitcoins are now mined using specialized computers called ASIC bitcoin miners; nevertheless, amateurs and enthusiasts still have some success mining by joining a mining pool. What if we set up a mining rig powered by a Raspberry Pi and solar panels and "deducted" the cost of the equipment? As the number of miners for Bitcoins increases, the difficulty of mining rises, and the rewards for miners decrease, the industry has become very competitive. Despite this discouraging information, I've decided to move on with this plan and shift my focus to alternative crypto assets.
Since we are utilizing a Raspberry Pi rather than an ASIC bitcoin miner, individual crypto mining was not an option. Despite my best efforts, I could not locate any mining pools that supported the Raspberry Pi operating system among the many available for Windows and macOS. Since Linux miners are written for the x86 architecture, Raspberry Pi cannot participate in the mining process. Linux mining software that runs on x86 processors like those found on most personal computers is supported.
Please note that the purpose of this paper is to promote further study of blockchain technology and cryptocurrencies, not to create any of those assets. The techniques outlined here are workarounds that need to be endorsed by the developers. Instead, you can download the free software linked with your preferred mining pool and install it on your personal computer.
We'll first sign up for an account on minergate, a crypto mining pool with over 3.5 million users worldwide that supports Bitcoin, Gold, Zcash, Ethereum, Ethereum, and monero. Since Monero is the only crypto I have had success with, this guide will focus solely on that one.
Turn on your Raspberry Pi.
Press Ctrl-T or launch a Terminal window in Raspberry Pi OS using Desktop. Please use the standard login procedures while using Raspberry Pi Lite.
If you're already in the Terminal, you can install the updates and prerequisites immediately.
sudo apt-get update && sudo apt-get upgrade -y
sudo apt install git automake autoconf libcurl4-openssl-dev libjansson-dev libssl-dev libgmp-dev
cd cpuminer-multi
Please use the below three commands to compile the mining code. This process will take a few minutes if you're using a Raspberry Pi 4.
sudo ./autogen.sh
sudo ./configure
sudo ./build.sh
Let's begin monero mining once we've installed and set up the mining program on our Raspberry Pi. To activate the miner, run the following line in the Terminal, substituting YOUR EMAIL with the address you used to create your minergate account.
./cpuminer -a cryptonight -o stratum+tcp://xmr.pool.minergate.com:45700 -u YOUR_EMAIL
The mining software will begin running, and if you're lucky, you'll see some 'accepted' shares marked with a "yes."
Please log in to minegate/internal so we can inspect your Minergate Dashboard. This can be done on a PC or laptop using the Chromium web browser or on a Raspberry Pi using the Raspberry Pi Desktop interface. Find the Monero icon at the bottom of your screen. The ONLINE status will be displayed if Monero is connected and functioning correctly. Congratulations! You have started Monero mining!
Now that we have a basic understanding of blockchain and cryptocurrencies, the issue of which currency is superior naturally emerges. The original cryptocurrency was Bitcoin, but there are now thousands of others, each with unique characteristics.
Though Bitcoin transactions may be traced back to specific senders and recipients through their hash values, this is a significant drawback of the cryptocurrency.
Monero is a cryptocurrency with unique rules in this regard. It's likewise mineable and based on a blockchain, but unlike bitcoin, the transactions here are anonymous and difficult to track. This is why most exchanges will not let you buy or sell Monero and why mining is the best option if you want some.
Many more cryptocurrencies exist besides Bitcoin and Monero, such as the technically superior coins Ethereum and the humorous currency Dogecoin. The Raspberry Pi can be used to mine a large number of them.
We'll utilize the Crontab approach to ensure that our cryptocurrency miner is always running on our Raspberry Pi.
crontab -e
If you haven't already, you'll see the message "no crontab for pi, Choose an editor" when you try to set the crontab.
Select 1 and press Enter.
Clicking here will launch a new crontab file; once it has opened, go to the bottom and add the following command, substituting YOUR EMAIL with the email you used to sign up for your Minergate account.
@reboot sudo /cpuminer-multi/cpuminer -a cryptonight -o stratum+tcp://xmr.pool.minergate.com:45700 -u YOUR_EMAIL
To keep your crontab, hit Ctrl-X and then y.
Type "sudo reboot" into the Terminal to restart the Pi.
After being powered on for almost 8 hours, my Raspberry Pi 4 has successfully calculated 357 good shares. Successful miners receive compensation when their shares are valued. If I do the math and get the appropriate answer, but my Pi is slower than another computer, I get a bad share. Only the first miner will be compensated if a miner submits a valid response before anyone else. Every invalid share is a penalty for the miner because of the possibility of fraud. I began to worry when my first four shares were flagged as invalid.
357 good shares = 0.000001410642 Monero = 0.00015569 USD
For 8 hours, I earned $0.000100, which is less than a penny. I was required to have at least 0.05 Monero (equivalent to about $5.811 USD) to make a withdrawal. (As of the date this article was published, the exchange rate was.) To attain the minimum withdrawal criterion of 0.05 Monero would take me 3,762 years at a rate of accumulating 0.000001410642 Monero per 8 hours.
As was mentioned at the outset of this piece, the aim of this activity was education regarding bitcoin, not financial gain.
Mined cryptocurrency rewards are divided up based on hash rates and shares. My hash rate swung between 1.6 and 33.3 hashes per second. The pool averaged 10.27 MH/s, around 3 million times faster than my Pi. As a point of comparison, 1 MH/s equals 1,000,000 hashes/ sec.
Additionally, a tiny commission is added to your transactions by the Minergate. Choose a Pay Per Share structure or one based on chance (with more significant potential gain).
Many 'time out' and send line failed' errors appeared on my Pi as I wrote this essay. On occasion, a Pi reboot was required, but on other occasions, the miner resumed operations without any more intervention.
Even though my Raspberry Pi wasn't a "money maker" in the cryptocurrency mining game, we still had a great time seeing it effectively compute and accumulate excellent shares.
A person can easily mine bitcoins at home with minimal equipment. A powered external USB hub may be the way to go if you want to avoid shelling out the cash for a desktop PC. Bitcoin mining can be facilitated and made more profitable by using a powered external USB hub. Raspberry Pi version B, compatible with most PCs, is also readily available and inexpensive. You can use Bitcoins to buy and sell on websites or keep them safe in a digital wallet
when you have Bitcoins.
Remember that large commercial Bitcoin miners employing thousands of computers will be your main competition. Still, a Pi 4 mining system is a fantastic (and entertaining) method of earning Bitcoins with little work. Because of the high cost of maintaining the hardware, mining Bitcoin using a Pi 4 is not financially sound. For Bitcoin mining, you'll also need hardware that's up to the task.
To be sure, a Pi 4 mining system can be a fantastic (and entertaining) method of earning Bitcoins without much effort on your part. However, even if you only make a few Satoshi, you'll still gain valuable experience and knowledge, so it's a good use of time. Be mindful of your monthly electricity costs, though.
Although you might make a few dollars mining on a Raspberry Pi, you won't become filthy rich overnight. Your electric bill may skyrocket if you've amassed a sizable Raspberry Pi fleet for mining. You can generate a small profit with a solar panel designed for the Raspberry Pi. The revenues won't make you rich, though; mining Monero with a Pi 4 and 100H/s of hashing power will net you just $1 per year. Making an annual average of $20 from mining using a USB miner is possible with Bitcoin.
We have developed a cryptocurrency miner that generates no additional costs whatsoever. The hash rate is a severe drawback of this design. Bitcoin mining on the Pi 4 is only profitable if the values of cryptocurrencies are supposed to remain the same. The upfront investment in equipment is more than the yearly return on investment from mining. One's perspective could alter if one were to speculate on the possibility of dramatically increasing prices. Those who are just sitting on unused hardware are in the same boat. A little setup is not worthwhile. The following guide will teach you how to set up a fingerprint sensor on your Raspberry Pi 4.
Thank you for being here for today's tutorial of our in-depth Raspberry Pi programming tutorial. The previous tutorial taught us how to install a PIR sensor on a Raspberry Pi 4 to create a motion detector. However, this tutorial will teach you how to connect a single seven-segment display to a Raspberry Pi 4. In the following sections, we will show you how to connect a Raspberry Pi to a 4-digit Seven-Segment Display Module so that the time can be shown on it.
Seven-segment displays are a simple type of Display that use eight light-emitting diodes to show off decimal numbers. It's common to find it in gadgets like digital clocks, calculators, and electronic meters that show numbers. Raspberry Pi, built around an ARM chip, is widely acknowledged as an excellent Development Platform. Its strong processing power can do amazing things in the hands of electronics enthusiasts and students. If we can figure out how to have it talk to the outside world and process data via an output, then we'll have a real chance of accomplishing all this. We analyze the data by viewing it on an LCD screen or other Display. Numerous sensors can detect specific parameters in the physical world and convert them to the digital world. It would never make sense to utilize a PI LCD panel to display a minimal quantity of information. Here, a 7-Segment or 16x2-Alphanumeric LCD panel is the preferred method of presentation.
There are few uses for a 7-segment display that don't need an LCD panel, even though a 16x2 LCD is preferable in most. If all you need to do is show some numbers, then an LCD, which has the downside of having a small character size, is excessive. Compared to a regular LCD screen, seven segments have the upper hand in dim environments and can be seen from wider angles. Let's get started.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Breadboard | Amazon | Buy Now | |
| 2 | Jumper Wires | Amazon | Buy Now | |
| 3 | Raspberry Pi 4 | Amazon | Buy Now | |
Jumper wires
Seven segment display
1KΩresistors
Breadboard
The seven segments of a 7 Segment Display are each lit up by an individual LED to show the digits. To show the number 5, for example, you would make the glow pins for segments a, f, g, c, and d on the 7-segment high. This particular 7-segment display is a Common Cathode version, although there is also a Common Anode version.
The wiring diagram for connecting a 7-segment display to a Raspberry Pi is shown below. Here, 7-Segment Common Cathode has been utilized.
So, we'll simulate an 8-bit PORT on PI using its eight GPIO pins. Here, GPIO12 is the Most Significant Bit (MSB), while GPIO13 is the Least Significant Bit (LSB) (Most Significant Bit).
If we wish to show the number 1, we must activate both segments B and C. We must supply voltage to GPIO6 and GPIO16 to power segments B and C. Accordingly, the hexadecimal value of "PORT" is "06," and the byte value of "PORT" is "0b00000110." If we raise both pins to their highest positions, the number "1" will be shown.
The value for every displayable digit has been recorded and saved in a Character String with the label 'DISPLAY .'We have then used the Function 'PORT' to call those values one at a time and display the relevant digit.
Once everything is wired up according to the schematic, we can power up the PI and begin using PYTHON to write the program. Below is a function that allows us to program the GPIO pins on the PI, and we'll go over the few commands we'll be using in the PYTHON program to do so. We are also changing the name of the GPIO pins in the hardware from "GPIO" to "IO," which will be used throughout the code.
import RPi.GPIO as IO
The general-purpose input/output (GPIO) pins we need to use may be occupied with other tasks. If that's the case, the program's execution will be interrupted by warnings. The below command instructs the PI to continue running the software regardless of the warnings.
IO.setwarnings(False)
Pin numbers on the board and pin functions can be used to refer to PI's GPIOs. This GPIO5 is similar to the one labeled "PIN 29" on the board. Here we specify whether the number 29 or the number 5 will stand in for the pin.
IO.setmode (IO.BCM)
To use the LCD's data and control pins, we have assigned those functions to eight of the GPIO pins.
IO.setup(13,IO.OUT)
IO.setup(6,IO.OUT)
IO.setup(16,IO.OUT)
IO.setup(20,IO.OUT)
IO.setup(21,IO.OUT)
IO.setup(19,IO.OUT)
IO.setup(26,IO.OUT)
IO.setup(12,IO.OUT)
If the condition between the brackets evaluates to true, the looped statements will be run once. The value of PIN13 would be HIGH if and only if bit0 of the 8-bit 'pin' is true. There are eight 'if else' conditions, one for each of bits 0 through 7, so that each LED in the seven-segment Display can be set to either the High or Low state, depending on the value of the corresponding bit.
if(pin&0x01 == 0x01):
IO.output(13,1)
else:
IO.output(13,0)
As x increases from 0 to 9, the loop will be run 10 times for each command.
for x in range(10):
The following command can create an infinite loop, with which the statements included within the loop will be run repeatedly.
While 1:
All other commands and functions have been commented on in the following code.
import RPi.GPIO as IO # calling for the header file, which helps us use GPIO's of PI
import time # calling for time to provide delays in the program
DISPLAY = [0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x67] # string of characters storing PORT values for each digit.
IO.setwarnings(False) # do not show any warnings.
IO.setmode (IO.BCM) # programming the GPIO by BCM pin numbers. (like PIN29 as‘GPIO5’)
IO.setup(13,IO.OUT) # initialize GPIO Pins as outputs
IO.setup(6,IO.OUT)
IO.setup(16,IO.OUT)
IO.setup(20,IO.OUT)
IO.setup(21,IO.OUT)
IO.setup(19,IO.OUT)
IO.setup(26,IO.OUT)
IO.setup(12,IO.OUT)
def PORT(pin): # assigning GPIO logic by taking the 'pin' value
if(pin&0x01 == 0x01):
IO.output(13,1) # if bit0 of 8bit 'pin' is true, pull PIN13 high
else:
IO.output(13,0) # if bit0 of 8bit 'pin' is false, pull PIN13 low
if(pin&0x02 == 0x02):
IO.output(6,1) # if bit1 of 8bit 'pin' is true, pull PIN6 high
else:
IO.output(6,0) #if bit1 of 8bit 'pin' is false, pull PIN6 low
if(pin&0x04 == 0x04):
IO.output(16,1)
else:
IO.output(16,0)
if(pin&0x08 == 0x08):
IO.output(20,1)
else:
IO.output(20,0)
if(pin&0x10 == 0x10):
IO.output(21,1)
else:
IO.output(21,0)
if(pin&0x20 == 0x20):
IO.output(19,1)
else:
IO.output(19,0)
if(pin&0x40 == 0x40):
IO.output(26,1)
else:
IO.output(26,0)
if(pin&0x80 == 0x80):
IO.output(12,1) # if bit7 of 8bit 'pin' is true, pull PIN12 high
else:
IO.output(12,0) # if bit7 of 8bit 'pin' is false, pull PIN12 low
While 1:
for x in range(10): # execute the loop ten times incrementing x value from zero to nine
pin = DISPLAY[x] # assigning value to 'pin' for each digit
PORT(pin); # showing each digit on display
time.sleep(1)
The process of displaying a single number character on a 7-segment display is complete. However, we'd need more than a single 7-segment display to express information with more than one digit. Therefore, we will use a 4-digit seven-segment display circuit for this session.
Four individual Seven-Segment Displays have been linked up here. For a 4-digit 7-segment display, we know that each module will have 10 pins, so there will be 40 pins total. Soldering that many pins onto a dot board would be a hassle for anyone; thus, I recommend that anyone using a 7-segment display do so by purchasing a module or creating their PCB. See below for a diagram of the relevant connections:
In the preceding diagrams, we can see that the A-lines of all four displays are linked together as one A, and the same is true for B, C.... up until DP, which is essential for understanding how the 4-digit seven-segment module functions. Put another way, if trigger A is activated, the state of all 4 A's should be high.
Nonetheless, this never occurs. The four extra pins labeled D0 through D3 (D0, D1, D2, and D3) let us select which of the four displays is driven high. As an illustration, if I want my output to appear solely on the second Display, I would set D1 to high and leave D0, D2, and D3 at low. Using pins D0–D3 and A–DP, we can easily choose which displays should be on and which characters should be shown.
Let's check the many options for interfacing this 4-digit seven-segment Display with the Raspberry Pi. As can be seen in the diagram below, there are 16 pins on the 7-segment module. Even if your module's resources are limited, it will provide at least the following.
Segmented pins, either 7 or 8 segments (pins 1 to 8)
Pin holder to the ground (here pin 11)
A 4-digit code to unlock the door (pins 13 to 16)
See below for the wiring diagram of a digital clock built with a Raspberry Pi and a 4-digit Seven-segment display module:
You can also use the following table to ensure your connections are correct and follow the diagrams.
Locating the module's pins is the first step in making electrical connections. Identifying the Raspberry Pi's GPIO pins can be tricky; I've included an image to help.
Here, RPi is programmed in the Python programming language. The Raspberry Pi can be programmed in a wide variety of ways. Since Python 3 has become the de facto standard, we've opted to use that version as our integrated development environment (IDE). At the bottom of this guide, you'll find the whole Python code.
We'll go over the PYTHON instructions we'll be using for this project: first, we'll import the library's GPIO file; next, using the below function, we'll be able to program the Pi 4's GPIO pins. We are also changing the name of the GPIO pins in the hardware from "GPIO" to "IO," which will be used throughout the code. We've brought in time and DateTime to get the current time from Rasp Pi.
import RPi.GPIO as GPIO
import time, DateTime
The GPIO pins we're trying to use are already being used for something else. The program's execution will be interrupted with warnings if this is the case. The PI will be instructed to disregard the errors and continue with the software using the below command.
IO.setwarnings(False)
The physical pin number and the corresponding function number can refer to PI's GPIOs. As with 'PIN 29,' GPIO5 is a physical component on the circuit board. In this case, we specify whether the number "29" or "5" will stand in for the pin. GPIO. In BCM notation, GPIO5 pin 29 will be represented by a 5.
IO.setmode (GPIO.BCM)
As is customary, we'll start by setting the pins to their default values; in this case, both the segment and digit pins will be used as outputs. In our code, we organize the segment pins into arrays and set their values to zero by declaring them to be GPIO.OUT.
segment8 = (26,19,13,6,5,11,9,10)
for segment in segment8:
GPIO.setup(segment, GPIO.OUT)
GPIO.output(segment, 0)
We do the same thing with the digital pins, but we set them to output and set them to zero by default.
#Digit 1
GPIO.setup(7, GPIO.OUT)
GPIO.output(7, 0) #Off initially
#Digit 2
GPIO.setup(8, GPIO.OUT)
GPIO.output(8, 0) #Off initially
#Digit 3
GPIO.setup(25, GPIO.OUT)
GPIO.output(25, 0) #Off initially
#Digit 4
GPIO.setup(24, GPIO.OUT)
GPIO.output(24, 0) #Off initially
Numbers on a seven-segment display must be formed into arrays. To show a single digit, we need to toggle the on/off status of all but the dot pin of the 7-segment Display. For the numeral 5, for instance, we can use this setup:
For all alphabets and numerals, there is an equivalent sequence number. You can write on your own or utilize the handy table provided.
Using this information, we can create arrays for each digit in our Python code, as demonstrated below.
null = [0,0,0,0,0,0,0]
zero = [1,1,1,1,1,1,0]
one = [0,1,1,0,0,0,0]
two = [1,1,0,1,1,0,1]
three = [1,1,1,1,0,0,1]
four = [0,1,1,0,0,1,1]
five = [1,0,1,1,0,1,1]
six = [1,0,1,1,1,1,1]
seven = [1,1,1,0,0,0,0]
eight = [1,1,1,1,1,1,1]
nine = [1,1,1,1,0,1,1]
Let's bypass the function in the code that would otherwise be executed before entering the while loop and begin displaying characters on our 7-segment Display. If you hook up a Raspberry Pi to the internet, it will read the current time and divide it into four separate variables. For instance, when the time is 10.45, the values assigned to h1 and h2 will be 1 and 0, while m1 and m2 will be 4 and 5, respectively.
now = DateTime.DateTime.now()
hour = now.hour
minute = now.minute
h1 = hour/10
h2 = hour % 10
m1 = minute /10
m2 = minute % 10
print (h1,h2,m1,m2)
These four numbers will be displayed on one of our four digits. The lines below can be used to convert a variable's value to a decimal. Here, we show the value in variables on the 7-segment Display by using the function print segment (variable) with the digit 1 set to the highest possible value. You may be asking why we turn off this digit and why there's a delay after that.
GPIO.output(7, 1) #Turn on Digit One
print_segment (h1) #Print h1 on segment
time.sleep(delay_time)
GPIO.output(7, 0) #Turn off Digit One
This is because the user will only be able to see the full four-digit number if all four digits are shown at once, and we all know that this isn't possible.
How, then, can we simultaneously show all four digits? With luck, our MPU is considerably quicker than the human eye. Therefore we offer one number at a time but exceptionally quickly. The MPU and segment display are given 2ms (variable delay time) to process each digit before we go on to the next. A human being cannot detect this 2ms lag; therefore, it appears as though all four digits illuminate simultaneously.
Understanding how to use print segment(variable) is the final puzzle piece. Arrays that have been declared outside of this function are used within it. As a result, the value of any variable passed to this function must be inside the range (0-9) so that the character variable can use in a meaningful comparison. Here, we check the variable against the value 1. The same is true for all comparisons with numbers between zero and nine. Assigning each value from the arrays to the appropriate segment pins is what we do if a match is found.
def print_segment(character):
if character == 1:
for i in range(7):
GPIO.output(segment8[i], one[i])
Use the provided schematic and code to connect your components and set up your Raspberry Pi. Once you've finished setting everything up, you can open the software and check the 7-segment Display to see the time. However, before doing this, you should check a few things.
If you want to be sure your Raspberry Pi isn't stuck in the past, you should update its time.
If you want to utilize a 7-segment display on your Raspberry Pi, you'll need to plug it into an adapter rather than a computer's USB connection because of the large amount of current it consumes.
import RPi.GPIO as GPIO
import time, DateTime
now = datetime.datetime.now()
GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
#GPIO ports for the 7seg pins
segment8 = (26,19,13,6,5,11,9,10)
for segment in segment8:
GPIO.setup(segment, GPIO.OUT)
GPIO.output(segment, 0)
#Digit 1
GPIO.setup(7, GPIO.OUT)
GPIO.output(7, 0) #Off initially
#Digit 2
GPIO.setup(8, GPIO.OUT)
GPIO.output(8, 0) #Off initially
#Digit 3
GPIO.setup(25, GPIO.OUT)
GPIO.output(25, 0) #Off initially
#Digit 4
GPIO.setup(24, GPIO.OUT)
GPIO.output(24, 0) #Off initially
null = [0,0,0,0,0,0,0]
zero = [1,1,1,1,1,1,0]
one = [0,1,1,0,0,0,0]
two = [1,1,0,1,1,0,1]
three = [1,1,1,1,0,0,1]
four = [0,1,1,0,0,1,1]
five = [1,0,1,1,0,1,1]
six = [1,0,1,1,1,1,1]
seven = [1,1,1,0,0,0,0]
eight = [1,1,1,1,1,1,1]
nine = [1,1,1,1,0,1,1]
def print_segment(charector):
if charector == 1:
for i in range(7):
GPIO.output(segment8[i], one[i])
if charector == 2:
for i in range(7):
GPIO.output(segment8[i], two[i])
if charector == 3:
for i in range(7):
GPIO.output(segment8[i], three[i])
if charector == 4:
for i in range(7):
GPIO.output(segment8[i], four[i])
if charector == 5:
for i in range(7):
GPIO.output(segment8[i], five[i])
if charector == 6:
for i in range(7):
GPIO.output(segment8[i], six[i])
if charector == 7:
for i in range(7):
GPIO.output(segment8[i], seven[i])
if charector == 8:
for i in range(7):
GPIO.output(segment8[i], eight[i])
if charector == 9:
for i in range(7):
GPIO.output(segment8[i], nine[i])
if charector == 0:
for i in range(7):
GPIO.output(segment8[i], zero[i])
return;
while 1:
now = DateTime.DateTime.now()
hour = now.hour
minute = now.minute
h1 = hour/10
h2 = hour % 10
m1 = minute /10
m2 = minute % 10
print (h1,h2,m1,m2)
delay_time = 0.001 #delay to create the virtual effect
GPIO.output(7, 1) #Turn on Digit One
print_segment (h1) #Print h1 on segment
time.sleep(delay_time)
GPIO.output(7, 0) #Turn off Digit One
GPIO.output(8, 1) #Turn on Digit One
print_segment (h2) #Print h1 on segment
GPIO.output(10, 1) #Display point On
time.sleep(delay_time)
GPIO.output(10, 0) #Display point Off
GPIO.output(8, 0) #Turn off Digit One
GPIO.output(25, 1) #Turn on Digit One
print_segment (m1) #Print h1 on segment
time.sleep(delay_time)
GPIO.output(25, 0) #Turn off Digit One
GPIO.output(24, 1) #Turn on Digit One
print_segment (m2) #Print h1 on segment
time.sleep(delay_time)
GPIO.output(24, 0) #Turn off Digit One
#time.sleep(1)
A similar section should appear below if everything is functioning as it should.
Typically, only 16 hexadecimal digits can be shown on a seven-segment display. Some show the digits 0-9, whereas others can show more. Seven-segment displays can only show a maximum of 16 values due to a lack of input leads. However, LED technology does allow for more than this. Even with the help of integrated circuit technology, the possible permutations of the seven parts on the screen are very few.
This guide taught us how to connect a 7-segment screen to a Raspberry Pi 4. The seven-segment Display, which we learned is employed in digital timers, clocks, and other electrical gadgets, are a cheap, basic electrical circuit and reliable module. Seven-segment displays can either be "common-anode" (where the common point is the power input) or "common-cathode" (where the common end is grounded). After that, we coded some python scripts to show numbers on a single seven-segment model and the time across four such screens. Next, we'll see how to use a Raspberry Pi 4 as the basis for a low-power Bitcoin miner.
Thank you for being here for today's tutorial of our in-depth Raspberry Pi programming tutorial. The previous tutorial demonstrated the proper wiring of the photoresistor sensor to the GPIO pins. Finally, we learned how it might be included in a Python script for data collection and analysis needs. We also looked at the functions of each component in the circuit. However, I'll walk you through installing a Pi 4 Print Server in this guide. While installing the program is straightforward, setting it up so that a Windows network can locate the print server requires a little more effort. Rather than spending hundreds of dollars upgrading to a laser printer, you may easily upgrade your current USB printer to laser quality by installing a print server.
Because of this software, you no longer have to have the printer physically linked to a single computer, and you may place it wherever you choose and share it with as many computers as you like. In addition, it's a fantastic method of printer sharing that eliminates the need for a pricey tower computer to be on and active all the time. CUPS is the program we'll be using to make this happen. Common Unix Printing System, or CUPS, is the foundation of Linux printing applications. But, the program facilitates communication between your computer and printer. It would help if you visited available printing to verify that the CUPS printing software supports your printer model.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry Pi 4
Wi-Fi
USB Printer
Since the Raspberry Pi print server is included in the Debian Jessie distribution, setting it up is a breeze. In this lesson, I'll be using Raspbian, so if you're unfamiliar with it and would like to learn how to set it up, check out my guide on how to do so.
We must ensure the Raspberry Pi is up-to-date with the most recent software to get started. Just type in the appropriate instructions into the terminal to accomplish this.
sudo apt update
sudo apt upgrade
We can begin setting up the print software after the Pi 4 has been upgraded. Here, we will be setting up CUPS.
CUPS, short for Common Unix Printing System, is a printing system designed for computers running UNIX-like operating systems. The software transforms the host computer into a print server. A CUPS-enabled server may receive print jobs from various client devices, sort them, and send them to the correct printer for output. Conveniently, this program can handle the administration of your printers, whether they're linked locally through USB or remotely via the network. Using the terminal, enter the following command to install the software. Considering HP has CUPS that support its open source project, HP printers, in particular. Even if your specific printer model isn't listed as being directly supported by CUPS, you may still be able to find a compatible generic driver online that will get the job done. These links will take you to a list of CUPS-compatible printers.
sudo apt install cups
We still have some work to do after CUPS's installation is complete. The first step is to include the pi user in the lpadmin set of users. With this group, the pi user can manage CUPS settings without logging in as the superuser.
sudo usermod -a -G lpadmin pi
To make sure it functions properly on your home network, there is one more thing we must do to CUPS: make it available to every computer on your network. At this time, Cups is configured to refuse connections from addresses outside the local network. By entering the following two commands, we can make it listen to all incoming connections:
sudo cupsctl --remote-any
sudo systemctl restart cups
After this, any machine on the network can send prints to the Pi 4 print server. The following command can be used if you need to know your Raspberry Pi's local IP Address.
hostname -I
If you know your Raspberry Pi's IP address, you can use it to access the website at the address below. Be sure to replace "192.168.1.105" with your IP address.
We'll examine how to configure SAMBA so that Windows can find the Raspberry Pi print server. Furthermore, we will demonstrate how to install a printer using the CUPS interface.
A proper SAMBA configuration is required if you use your print server in conjunction with Windows. To get SAMBA up and running with the CUPS print drivers, we'll have to install it and tweak its settings.
First, check that SAMBA is installed; to do so, we can use the terminal's built-in install command. Just by typing this into the terminal, we can accomplish our goal.
sudo apt install samba
Now that SAMBA is installed on our Pi 4, we can access its config file and make some changes. The following command will cause the file to be opened in the nano text editor:
Sudo nano /etc/samba/smb.conf
Once the file has been opened, it must be scrolled to the end. To do this quickly, press the Control key plus the V key. The following lines should be added or edited once you reach the very end of the file. The file already contained the "[printers]" and "[print$]" sections; all I had to do was update the values to reflect the following.
[printers]
comment = All Printers
browseable = no
path = /var/spool/samba
printable = yes
guest ok = yes
read only = yes
create mask = 0700
[print$]
comment = Printer Drivers
path = /var/lib/samba/printers
browseable = yes
read only = no
guest ok = no
To save the file, hit CTRL+X, Y, and ENTER. SAMBA needs to be restarted to pick up the updated settings. The following command, when entered into the terminal, will restart SAMBA.
sudo systemctl restart smbd
It's easy to set up a printer using CUPS, but first, we need to open the program's graphical user interface. For the IP address of your Raspberry Pi, enter "hostname" into the terminal.
hostname -I
To access the IP configuration page for your Raspberry Pi, type the following into your web browser and enter the IP address you just jotted down. Replace "192.168.1.105" with your IP address when entering this address.
The following homepage is what you should see. Here, we'll go to "Administration" on the main menu.
You'll be directed to Cups's control panel when you click here. On this page, select the "Add Printer" option.
The "Add Printer" screen has been brought up, allowing us to choose the printer we wish to configure Cups with. That printer is a Canon MG2500 series machine. When you've made your print choices, click the "Continue" button.
Ensure the printer is turned on and plugged into the Raspberry Pi through a USB connection if it does not appear here. If your Raspberry Pi still doesn't show up, try restarting it while ensuring your printer is on and connected.
Choose your printer's model from the dropdown menu here. CUPS will automatically identify the printer model and install the appropriate driver when possible. However, this may only sometimes work, so you may need to sift through the list to locate the proper driver manually. Once you've double-checked everything and are pleased, click the "Add Printer" button.
After completing the steps on this screen, the printer will have been added successfully. Here, you can give it a name and a summary that mean whatever you choose. If you have more than one printer in your residence, specifying its location will make your life easier. If you want other computers to be able to use the printer, you must also turn on "Share This Printer." If everything looks good, hit the "Continue" button.
After finishing the printer setup process, you will see the screen shown in the image below. Several of the printer's more nuanced settings are accessible through this panel—the number of pages printed, the quality of the printout, and so forth.
Having finished setting up our Raspberry Pi print server, we will now discuss how to add it to Windows. Having SAMBA set up earlier in the course should make this step less painless.
Installing a CUPS printer on Windows requires selecting the driver that will allow Windows to communicate with and comprehend the printer. Launching "My Computer" or "This PC" and then clicking "network" in the left-hand navigation pane is a quick method to get to Windows' network page, where you can get started. When you get there, you should see a screen like the one below, where your Raspberry Pi's hostname (in my instance, RASPBERRYPI) is displayed. If you double-click your Raspberry Pi's share, it may prompt you to log in. If entering anything other than "enter" fails to log you in, try "pi."
The printers used with your Pi 4 print server should now be displayed on the screen. Select the printer you wish to use by double-clicking on it.
You'll see the cautionary message below if you try to double-click this. Select "OK" to proceed with the tutorial.
Select your printer brand on the left, and then select your printer model from the available drivers for that brand on the right. If your printer isn't listed here, you can identify its model online and install the necessary drivers. For me, that meant tracking down the Canon MG2500 series. When you've decided which printer to use, you may move forward by clicking the "Ok" button.
The procedure will now initiate a link to your printer. Select "Printer" > "Set as Default Printer" to make this the system's default printer.
Now that the printer has been installed on your computer, you can use it with any application that supports printing. By printing a test page, you may verify that the printer is configured correctly.
If you're having trouble printing a file, check to see if you've picked the correct printer driver in CUPS and Windows. Ensure the printer is turned on as well; the Canon MG2500 series, for example, do not immediately restart when a print job is delivered. Adding Apple AirPrint capability to your Pi 4 print server is a great way to expand its capabilities.
Apple's AirPrint printing technology eliminates the requirement for users of Apple products to acquire and install the separate printing software. By adding AirPrint functionality, you may quickly and effortlessly print from your iOS smartphone to any nearby printer. You can run an AirPrint server from your Raspberry Pi, and Cups is the software that will power it. It will take care of talking to your printer on your Raspberry Pi's behalf.
The "Avahi daemon" must be set up before AirPrint may be used on your computer. The following command will install the package onto your Raspberry Pi.
sudo apt install avahi-daemon
Using this package, you can make Apple's Zeroconf design a reality. Bonjour has become widely used to refer to this type of network architecture. Using Bonjour, AirPrint can link disparate gadgets like an iPhone and a Raspberry Pi. Once you've selected the files you'd like to print, the Bonjour daemon will forward them to the designated printer.
Let's restart the machine to see whether the AirPrint server has worked appropriately, and everything is ready. Execute this command to force the Raspberry Pi to restart.
sudo reboot
After rebooting your Raspberry Pi, you can check to see if anything went wrong. This should get you to the point where you can print from any AirPrint-enabled device.
Have you succeeded in following this guide and setting up a Pi 4 network print server? If you've followed these steps carefully, your Raspberry Pi should be ready to function as a network AirPrint server. We were able to accomplish this by putting the Avahi daemon in place. This daemon implements the bonjour protocol used by AirPrint. Feel free to leave a message below if you have any thoughts, suggestions, or problems you'd want to discuss. The following tutorial will review the steps for monitoring a patient's heart rate with a Raspberry Pi 4.
We're glad you could join us for another lesson in our comprehensive Raspberry Pi programming guide. I will show you how to install and connect the RFID card chip to your Raspberry Pi through step-by-step instructions.
Modern security systems would only be complete using radio frequency (RFID) devices. To control who can enter a facility or which rooms they can access, RFID chips and card readers are employed. The RFID card's unique identification number can be read wirelessly with a wall-mounted RFID reader. A door will only unlock and allow entry if the RFID card's unique identification number matches a list of approved cards.
It's fun to tinker with this circuit, and it may be used in many other applications, from opening locks to taking attendance. The MFRC522 microcontroller underpins the RFID RC522, a cheap RFID (Radio-frequency identification) reader/writer. The RFID tags can connect with this microcontroller using an electromagnetic field it generates at 13.56MHz and sends to them via the SPI protocol. If you want to use your RFID RC522 with tags, you must ensure that they are 13.56MHz compatible. We'll walk you through the wiring of the RC522 and the creation of Python programs to communicate with the chip, allowing you to read and write RFID tags. Adding a 16x2 LCD to the Raspberry Pi is a simple extension of this tutorial, and it can be helpful if you need to show the user some information or provide a visual prompt.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Breadboard | Amazon | Buy Now | |
| 2 | Jumper Wires | Amazon | Buy Now | |
| 3 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry Pi
Micro SD Card
Power Supply
RC522 RFID Reader
Breadboard
Breadboard Wire
An RFID reader reads the tag's data when a Rfid card is attached to a specific object. An RFID tag communicates with a reader via radio waves.
In theory, RFID is comparable to bar codes because it uses radio frequency identification. While a reader's line of sight to the RFID tag is preferable, it is not required to be directly scanned by the reader. You can only read an RFID tag up to three feet away from the reader. The RFID tech quickly scans many objects, making it possible to identify a specific product rapidly and effortlessly, even if it is sandwiched between several other things.
Major components of Cards and tags include an integrated circuit (IC) that stores the unique identification value and a copper that acts as the antenna.
Inside the Rfid reader is another copper wire coil. This coil produces a magnetic field when current flows through it. Magnetic flux creates a current inside the wire coil when the card is brought close to the reader. This current can power the card's internal integrated circuit. The reader then takes in the card's serial number. A card reader will send the card's serial number to a central processing unit (CPU) like a Raspberry Pi for further processing.
When you buy an RFID RC522 Reader, you may discover that 90% of them do not have the header pins pre-installed. Due to a lack of pins, you'll have to solder them yourself; however, this is a relatively easy task, even for amateurs. Assuming the header pins that came with your RC522 are too large, you may snap them in half to reduce them to a single column of eight.
Start by inserting the header pins into the RC522 from the top. The circuit may be easily placed on top of the connector pins by inserting the large side of the pins onto a breadboard. The breadboard's secure holding of the pins will make soldering them to the RFID circuit much simpler.
Solder each pin individually by carefully heating your soldering iron and applying it to the pins. Remember that heating the junction slightly before to solder application increases the solder's adhesion and decreases the likelihood of generating a cold joint. When using solder, we advise you to be conservative. When you've finished soldering the header pins onto your RFID circuit, you'll be ready to move on with the guide.
There are eight different connectors on the RFID RC522. Except for the IRQ, we need to connect all these to the GPIO pins on our Raspberry Pi.
This guide shows how to connect an RFID RC522 to a Breadboard and then to the Raspberry Pi's GPIO Pins, although you could also wire the components straight to the Pi.
Simply connecting 7 of the Raspberry Pi's GPIO pins to the RFID RC522 reader is all needed to get it up and to run. Refer to the GPIO pin locations detailed in our tutorial and the table below when deciding how to wire your RC522.
SDA connects to Pin 24.
SCK connects to Pin 23.
MOSI connects to Pin 19.
MISO connects to Pin 21.
GND connects to Pin 6.
RST connects to Pin 22.
3.3v connects to Pin 1.
We need to adjust the Raspberry Pi's settings before we can use the RFID RC522. Inconveniently, our RFID reader circuit relies on the Raspberry Pi's SPI (Serial Peripheral Interface), which is disabled by default. Worry not, though, as it is easy to restore this interface; follow our instructions below to set up your RPi and Raspbian to use the SPI port. Launch the raspi-config utility by opening a terminal and typing the following command.
sudo raspi-config
A menu of choices will appear when you use this tool. You may read up on all of these options in the raspi-config documentation. Choose "5 Interfacing Options" using the arrow keys. Select this choice, and then hit the Enter key. Once "P4 SPI" is selected in the next screen, press Enter once more to confirm your selection. To continue, use the arrow keys to choose "Yes" and then press Enter when prompted to confirm that you want to activate the SPI Interface. For the raspi-config utility to finish enabling SPI, you'll have to be patient for a while.
The raspi-config tool's success in enabling the SPI interface will be shown by the display of the message "The SPI interface is enabled." Activating the SPI Interface requires a full reboot of the Raspberry Pi. Press Enter, and then ESC, to return to the terminal. If you want to restart the RPi, enter the following Unix instruction into the terminal.
sudo reboot
It is time to verify that Raspberry Pi has been activated now that it has rebooted. Checking if spi bcm2835 is available is as simple as running the following command.
lsmod | grep spi
If you get spi bcm2835, you're good to go with the rest of the tutorial. If you tried the preceding command and it didn't work, try the following three things. If the SPI component is not enabled, we can manually modify the boot config file by issuing the following code to our RPi.
sudo nano /boot/config.txt
You can use CTRL + W to search the configuration file for "dtparam=spi=on" If you think you have discovered it, look if it has a number in front of it. If there is, delete it because it disables the code. If you cannot find the line, add "dtparam=spi=on" to the very end of the file. To commit your modifications, use CTRL + X, followed by Y and Enter. You can double-check that the module has been activated by restarting your Raspberry Pi, as in Step 5.
After connecting our RFID circuit to the RPi, we can turn it on and start writing Python scripts to communicate with the chip. You'll learn how to read and write information to RFID chips by composing scripts like the ones we'll provide. These will serve as the foundation for future RFID RC522 tutorials and provide you with a fundamental understanding of how data is handled. The Raspberry Pi must be brought up to date with the most recent software versions before we can begin programming. Get the latest version of Raspbian for your Pi by running these two commands.
sudo apt update
sudo apt upgrade
Installing the python3-dev, python-pip, and git packages is the last thing to do before moving forward. To get your RFID reader set up with this guide, type the following command into your Raspberry Pi's terminal.
sudo apt install python3-dev python3-pip
Now that we have python "pip" installed on our Raspberry Pi, we can install the spidev Python library. An integral part of this guide, the spidev library allows the RPi to communicate with the RFID via the SPI. Run the following command to get spidev set up on your Raspberry Pi via pip. It's important to remember that we're using sudo to guarantee that the package gets installed for everyone's usage, not just the logged-in user.
sudo pip3 install spidev
After getting the spidev library up and running on our Raspberry Pi, we'll move on to setting up the MFRC522 library with pip. Two files, in particular, are used by us, both of which are part of the MFRC522 library:
This library, MFRC522.py, implements the RC522 interface for communicating with RFIDs via Raspberry Pi's SPI port.
Simplifying the MFRC522.py file so that you only need to work with a small subset of its many functions, SimpleMFRC522.py is a significant time saver.
Enter this command into your terminal to have pip setup the MFRC522 library on your Pi 4:
sudo pip3 install mfrc522
Now that the library has been transferred to the Pi, we can start writing code for the RFID RC522. First, we'll explore how to use the RC522 to program your RFID cards. Move on to the following part, where we will write our first Python code.
In this first Python script, we'll go over the steps needed to send information from the RC522 to RFID tags. This is made more accessible by the SimpleMFRC522 script, but we'll still break down the code's individual components for you. To begin, let's create a directory to hold the scripts we'll be using. Create the "pi-RFID" folder by using the following command.
mkdir ~/pi-rfid
To get started, navigate to the folder you just cloned and create the Write.py script in Python.
cd ~/pi-RFID
sudo nano Write.py
Add the following blocks of code to this file. This code prompts you for some text, which it then uses to update the RFID Tag.
#!/usr/bin/env python
import RPi.GPIO as GPIO
from mfrc522 import SimpleMFRC522
The very first line of the code snippet instructs the terminal to use Python rather than another scripting language like Bash to parse and run the file. To guarantee that the GPIO Pins are reset when the script terminates, we must first import the RPi.GPIO package contains all the necessary functions for communicating with the GPIO Pins. The second import is our SimpleMFRC522 library, which will be used to communicate with the RFID RC522. Compared to the standard MFRC522 library, it dramatically simplifies working with the chip.
reader = SimpleMFRC522()
In this line, we make a new instance of the SimpleMFRC522 object, use its setup function, and save the result in our readers variable.
try:
text = input('New data:')
print("Now place your tag to write")
reader.write(text)
print("Written")
We enclose the following section of code with a try statement to ensure that any unforeseen problems are handled, and the code is cleaned up correctly. Python is whitespace sensitive; it uses tabs to distinguish between code sections, so keep them after trying. In this case, the second line reads a command-line input and stores it in a text variable using Python 3's input function.
The third line makes advantage of print() to prompt the user to set the RFID tag onto the reader. After that, on line 4, we utilize our scanner object to instruct the RFID Circuit to write the text field's contents to a certain sector of the RFID tag. On line 5, after successfully writing to the RFID tag, we call print() once more to inform the user.
finally:
GPIO.cleanup()
The script will terminate in the last two lines of code. The finally statement always follows the try statement. Thus the GPIO.cleanup() method is called after each iteration of the try block. These lines are essential because improper cleanup can disrupt the functionality of other programs. Upon completion, your script should be like the example given below.
The file can be saved by pressing CTRL Plus X, Y, then ENTER once you've double-checked the code and are convinced it's correct. Now that the script is written, we need to put it through some testing. Get an RFID tag ready before running the script for testing. When you're ready, open the terminal on your Raspberry Pi and enter the following command.
sudo python3 Write.py
In this situation, we're just going to type in "any word" because it's easy to remember and short. Press the Enter key when you have finished writing and are ready to send. After that, your RFID Tag can be placed directly above your RFID circuit. It will immediately update the tag with fresh information when it does. You'd see the word "Written" on the command prompt if it worked. Now that you have your Write.py script completed, we can move on to explaining how to read information from the RFID RC522.
We have successfully programmed our RC522 to print to RFID tags and can now move on to writing a script to retrieve the data from the tags. First, we'll make sure we're in the correct location by switching directories, and then we'll use nano to start drafting the Read.py script.
cd ~/pi-rfid
sudo nano Read.py
Incorporate the following code into this document. When an RFID tag is placed in the RFID reader, the script will wait until the tag's data has been read before displaying the results.
This file's first line of code instructs the operating system on how to proceed when the user clicks the "Run" button. If you don't specify that it's a Python file, it'll try to run it like any other script. An initial RPi.GPIO import is made. Importing this library ensures that the Raspberry Pi's GPIO pins are cleaned up after script termination, as it contains all the necessary functions. SimpleMFRC522 is the second import. With the assistance functions included in this script, reading and writing to an RFID RC522 is a breeze, whereas, with them, the scripts would quickly grow to be manageable.
This line is crucial because it invokes SimpleMFRC522's creation method, which returns an object that is subsequently stored in our reader variable.
try:
id, text = reader.read()
print(id)
print(text)
The following code section will be encapsulated in a try block to allow us to handle any unforeseen errors gracefully. Because Python is sensitive to whitespace, you must use the 'tabs' as displayed following try:
In this scenario, the second line of this code block initiates a call on our scanner object, instructing the circuits to begin scanning any Rfid card that is positioned on top of the reader. On the third and forth lines, we use print() to display the data we gleaned from the RFID Chip; this includes the tag's unique identifier and any text it may consist of.
finally:
GPIO.cleanup()
The script ends with the last two lines of code. No of what happens inside the try block, the final statement is always executed afterward. No matter what, the GPIO.cleanup() code will be executed thanks to this try statement. It's vitally important, as not doing so can disrupt the proper operation of other scripts that rely on the GPIO. Your completed Read.py script for the RFID RC522 should resemble the example below.
When you've double-checked your code and are satisfied with it, press Ctrl + X, then Y, and finally ENTER to save the file. The time has come to put our completed Read.py script to the test. Get ready to test the script by picking up any of the RFID tags. If you're all set, enter this command into the terminal on your Raspberry Pi.
sudo python3 Read.py
Now that the script is active, you can set your RFID Tag atop your RFID circuit. When the RFID tag is placed on top, the Python program will immediately begin reading the information from the tag and display the results on the screen. What a finished product might look like is shown below as an illustration.
To test whether your Raspberry Pi is properly connected on the RFID RC522 Circuit, run the Read.py script and see if it returns any data that matches the text you wrote to the card in the Write.py script.
Connecting an RC522 RFID module to a Pi 4 makes reading MIFARE chips and cards is now possible. This might be very useful in security systems and other applications where identifying an item or person is required without the user having to physically interact with the device by pressing buttons, switching, or activating any sensors. Eventually, you should be able to use this to decipher the UID encoded on your MIFARE tags. You should know that these cards can be duplicated and assigned a new unique identifier (UID) if you plan on employing this technique in a security system. To ensure the safety of your system, you must ensure that no one learns your UID or gains remote access to your devices. The contactless tags are convenient because they can be attached to a keychain, and the cards are convenient because they can be carried in a wallet. Both things can be concealed inside others to give them a hidden identifier that the Pi can access. With the help of our Pi 4-powered RFID attendance systems guide, you can learn how to set up your RFID Reader/Writer for use in checking attendance. Our exploration of the RFID chip and the scripts above will continue in subsequent guides. A door security system is one of the fantastic DIY Pi ideas we'll look into. The next lesson will teach you how to connect a 16x2 LCD screen to a Raspberry Pi 4.
Greetings, and welcome to today's tutorial. In the last tutorial, we learned how to construct a system for tallying individuals using Raspberry Pi, astute subtraction, and blob tracking. We demonstrated the total number of building entrances and exits. Feature computation and HOG theory were also discussed. The tests proved that a device based on the raspberry pi could effectively function as a people counting station. One of the many benefits of the Pi 4 is its internet connectivity, which is especially useful for home automation projects due to its low price and ease of use. We're going to see if we can use a web page's buttons to manage our air conditioner today. With this Internet of Things (IoT) based home automation, you can command your home gadgets from the comfort of your couch. The user can access this web server from any gadget capable of loading HTML apps, such as a smartphone, tablet, computer, etc.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Breadboard | Amazon | Buy Now | |
| 2 | Diodes | Amazon | Buy Now | |
| 3 | Jumper Wires | Amazon | Buy Now | |
| 4 | LEDs | Amazon | Buy Now | |
| 5 | Resistor | Amazon | Buy Now | |
| 6 | Transistor | Amazon | Buy Now | |
| 7 | Raspberry Pi 4 | Amazon | Buy Now | |
The needs of this project can be broken down into two broad classes: hardware and software.
Raspberry Pi 4
Memory card 8 or 16GB running Raspbian Jessie
5v Relays
2n222 transistors
Diodes
Jumper Wires
Connection Blocks
LEDs to test.
AC lamp to Test
Breadboard and jumper cables
220 or 100 ohms resistor
We'll be using the WebIOPi framework, notepad++ on your PC, and FileZilla to transfer files (particularly web app files) from your computer to the raspberry pi and the Raspbian operating system.
As a good habit, I constantly update the Raspberry Pi before using it for the first time. In this project phase, we will handle the web-to-raspberry-pi connection by upgrading the Pi and setting up the WebIOPi framework. The python Flask framework provides a potentially more straightforward alternative, but getting your hands dirty and looking at how things operate makes DIY appealing. When you get to that point, the fun of DIY begins. Use the updated commands below to upgrade your Raspberry Pi and restart the RPi.
sudo apt-get update
sudo apt-get upgrade
sudo reboot
After this is finished, we can set up the webIOPi framework. Using, verify that you are in your home directory.
cd ~
To download the files from the google page, type wget.
wget http://sourceforge.net/projects/webiopi/files/WebIOPi-0.7.1.tar.gz
Then, once the download is complete, unzip the file and enter the directory;
tar xvzf WebIOPi-0.7.1.tar.gz
cd WebIOPi-0.7.1/
Unfortunately, I could not locate a version of WebIOPi that is compatible with the Pi 4; thus, we have to download a patch before proceeding with the setup. Run the instructions below from within the WebIOPi directory to apply the patch.
wget https://raw.githubusercontent.com/doublebind/raspi/master/webiopi-pi2bplus.patch
patch -p1 -i webiopi-pi2bplus.patch
Once we have those things, we can begin the WebIOPi setup installation process by using the;
sudo ./setup.sh
Just click "Yes" when prompted to install more components during setup. Upon completion, restart your Pi.
sudo reboot
Before diving into the schematics and programs, we should power on the Raspberry Pi and ensure our WebIOPi installation is functioning as expected. Execute the command below;
sudo webiopi -d -c /etc/webiopi/config
After running the above command on the pi, open a web browser and navigate to http://raspberrypi.mshome.net:8000 (or HTTP;//thepi'sIPaddress:8000) on the computer that is attached to the pi. When logging in, you'll be asked for a username and password.
Username is webiopi
Password is raspberry
You may permanently disable this login if you no longer need it. Still, it's important to keep unauthorized users from taking control of your home's appliances and Internet of Things (IoT) components. After you've logged in, go to the GPIO header link.
Make GPIO 17 an output; we'll use it to power an LED in this Test.
Following this, attach the led to the Pi 4 as depicted in the schematics.
When you're ready to activate or deactivate the LED, return to the web page where you made the connection and select the pin 11 button. This allows us to use WebIOPi to manage the Raspberry Pi's GPIO pins. If the Test is successful, we can return to the console and exit the program by pressing CTRL + C. Please let me know in the comments if this arrangement has any problems. Once the pilot is finished, we can begin the actual project.
In this section, we will alter the WebIOPi service's standard setup and inject our code to be executed on demand. FileZilla or another FTP/SCP copy program will be the first tool we install on our computer. You'll agree that using the terminal to write code on the Pi is a stressful experience, so having access to Filezilla or another SCP program will be helpful. Let's make a project directory in which all our web scripts will be stored before we begin writing the HTML, CSS, and javascript programs for this Internet - of - things Home automated Web app and transferring them to the RPi.
First, make sure you're in your home directory using; next, create the folder; finally, open the newly constructed folder and make an HTML folder inside it.
cd ~
mkdir webapp
cd webapp
mkdir HTML
Make subfolders inside the HTML folder for scripts, CSS, and graphics.
mkdir html/css
mkdir html/img
mkdir html/scripts
Now that we have our files prepared, we can start coding on the computer and transfer our work to the Pi using Filezilla.
Writing the javascript will be our first order of business. An easy-to-use script for interacting with the WebIOPi server. Our four-button web app will only use two relays in the demonstration, and we only intend to control four GPIO pins for this project.
webiopi().ready(function() {
webiopi().setFunction(17,"out");
webiopi().setFunction(18,"out");
webiopi().setFunction(22,"out");
webiopi().setFunction(23,"out");
var content, button;
content = $("#content");
button = webiopi().createGPIOButton(17," Relay 1");
content.append(button);
button = webiopi().createGPIOButton(18,"Relay 2");
content.append(button);
button = webiopi().createGPIOButton(22,"Relay 3");
content.append(button);
button = webiopi().createGPIOButton(23,"Relay 4");
content.append(button);
});
Once the WebIOPi is ready, the preceding code is executed. To help you understand JavaScript, we've explained below:
webiopi().ready(function()
All this tells our system to make this function and call it once the webiopi is set.
webiopi().setFunction(23,"out")
We can instruct the WebIOPi program to use GPIO23 for output. Four buttons are now available, but you may add more if necessary.
var content, button
With this line, we're instructing the system to make a new variable called content into a button.
content = $("#content")
We will continue using the content variable in our HTML and CSS. As a result, the WebIOPi framework generates everything connected to #content when it is mentioned.
button = webiopi().createGPIOButton(17,"Relay 1")
WebIOPi can make several distinct types of push buttons. This code instructs the WebIOPi program to generate a GPIO key that operates on the GPIO pin identified as "Relay 1" above. The other ones are the same, too.
content.append(button)
Add this code to the button's existing HTML or external code. New buttons can be made that are identical to this one in every respect. This is especially helpful while coding or writing CSS.
If you made your JS files the same way I did, you can save them and then move them with Filezilla to webapp/HTML/scripts after you've finished making them. Now we can move on to developing the CSS.
With the aid of CSS, our Internet of Things (IoT) Rpi 4 home automation website now looks fantastic. So that the website will look like the one in the picture below, I built a custom style sheet called smarthome.css.
I don't want to paste the entire CSS script here, so I'll use a subset for the explanation. If you want to learn CSS, all you have to do is read the code. You can skip this and use our CSS code if you want to.
The first section of the script, displayed below, represents the web application's main stylesheet.
body {
background-color:#ffffff;
background-image:URL('/img/smart.png');
background-repeat:no-repeat;
background-position:center;
background-size:cover;
font: bold 18px/25px Arial, sans-serif;
color:LightGray;
}
The above code, which I hope needs no explanation, begins by setting the background colour to white (#ffffff), adds a background image to the document from the specified folder (remember the one we created earlier? ), makes sure the picture doesn't duplicate by setting the background-repeat to no-repeat, and finally tells the CSS to center the background. Next, we adjust the background's text size, font, and colour.
After finishing the main content, we styled the buttons with CSS.
button {
display: block;
position: relative;
margin: 10px;
padding: 0 10px;
text-align: center;
text-decoration: none;
width: 130px;
height: 40px;
font: bold 18px/25px Arial, sans-serif; color: black;
text-shadow: 1px 1px 1px rgba(255,255,255, .22);
-WebKit-border-radius: 30px;
-Moz-border-radius: 30px;
border-radius: 30px;
}
Everything else in the script is similarly optimized for readability and brevity. You can play with them and see what happens; this kind of learning is known as "learning by doing," I believe. However, CSS's strengths lie in its simplicity, and its rules are written in plain English. The button's text shadow and button shadow are two of the few supplementary features found in the block's other section. To top it all off, pressing the button triggers a subtle transition effect, making it look polished and lifelike. To guarantee optimal page performance on all browsers, these are defined independently for WebKit, firefox, opera, etc.
The following code snippet notifies the WebIOPi service that it is receiving data as input.
input[type="range"] {
display: block;
width: 160px;
height: 45px;
}
Providing feedback on when a button is pressed will be the last element we want to implement. As a result, the screen's colour scheme and button hues provide a quick indicator of progress. To accomplish this, the following line of code is added to each button's HTML.
#gpio17.LOW {
background-color: Gray;
color: Black;
}
#gpio17.HIGH {
background-color: Red;
color: LightGray;
}
The code snippets up top alter the button's color depending on the user's selection. The button's background is gray when it is inactive (at LOW) and red when it is active (at HIGH). Now that we have our CSS under control let's save it as smarthome.css, upload it to our raspberry pi's styles folder using FileZilla (or another SCP client of your choosing), and fix the remaining HTML code.
The HTML code unifies the style sheets and java scripts.
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="mobile-web-app-capable" content="yes">
<meta name="viewport" content = "height = device-height, width = device-width, user-scalable = no" />
<title>Smart Home</title>
<script type="text/javascript" src="/webiopi.js"></script>
<script type="text/javascript" src="/scripts/smarthome.js"></script>
<link rel="stylesheet" type="text/CSS" href="/styles/smarthome.css">
<link rel="shortcut icon" sizes="196x196" href="/img/smart.png" />
</head>
<body>
</br>
</br>
<div id="content" align="center"></div>
</br>
</br>
</br>
<p align="center">Push button; receive bacon</p>
</br>
</br>
</body>
</html>
The head tag contains several crucial elements.
<meta name="mobile-web-app-capable" content="yes">
The code line above makes it possible to add the web app to the mobile device's home screen when using Chrome or Safari. You can access this function using the Chrome menu. This makes it so the app may be quickly launched on any mobile device or desktop computer.
The following line of code provides a measure of responsiveness for the web app. Because of this, it can take up the entire display of any gadget on which it is run.
<meta name="viewport" content = "height = device-height, width = device-width, user-scalable = no" />
The web page's title is defined in the following line of code.
<title>Smart Home</title>
The following four lines of code all connect the Html file to multiple resources it requires to function as intended.
<script type="text/javascript" src="/webiopi.js"></script>
<script type="text/javascript" src="/scripts/smarthome.js"></script>
<link rel="stylesheet" type="text/CSS" href="/styles/smarthome.css">
<link rel="shortcut icon" sizes="196x196" href="/img/smart.png" />
The first line above directly connects to the WebIOPi framework JavaScript, which is stored in the server's root directory. This method must be invoked whenever WebIOPi is used.
The second line tells the HTML document where to find our jQuery script, and the third tells where to get our style sheet. The last line prepares an icon for the mobile desktop, which can be useful if we use the website as an app or a favicon.
To ensure that our HTML code displays whatever is contained in the JavaScript file, we include break tags in the body portion of the code. The definition of our button's content was made previously in the JavaScript code, and its id="content" should bring that to mind.
<div id="content" align="center"></div>
Everybody is familiar with the routine of saving an Html file as index.html and then transferring it to the Pi's HTML folder via Filezilla.
Before we can begin sketching out circuit diagrams and running tests on our web app, we need to make a few adjustments to the webiopi service's configuration file, instructing it to look for configuration information in our HTML folder rather than the default location.
Edit the configuration by executing the following commands as root:
sudo nano /etc/webiopi/config
Find the section of the configuration file labelled "HTTP" and look for the line that begins with "#" Modify the directory where HTML and resources are stored by default with doc-root.
Remove the # comments from anything below it, and if your folder is organized like mine, set the doc-root to the location of your project file.
doc-root = /home/pi/webapp/html
Lastly, save your work and exit. If you already have another server installed on the Pi utilizing port 8000, you may easily change it. If not, let's stop saving and call it a day.
It's worth noting that the WebIOPi service password can be changed using the command;
sudo webiopi-passwd
A new login name and password will be required. Getting rid of this entirely is possible, but safety comes first.
Finally, issue the following command to start the WebIOPi service.
sudo /etc/init.d/webiopi start
If you want to see how the server is doing, you can do so by;
sudo /etc/init.d/webiopi status
That's why there's a way to halt its execution:
sudo /etc/init.d/webiopi stop
Setup WebIOPi to start automatically with;
sudo update-RC.d webiopi defaults
To do the opposite and prevent it from starting up automatically, use the following;
sudo update-RC.d webiopi remove
Now that we have everything set up, we can begin developing the schematics for our Web-controlled home appliance.
Whereas I could not procure relay modules, which in my experience, make electronics projects simpler for do-it-yourselfers. So, I'm going to draw some diagrams for regular, single-relay, 5V-powered standalone devices.
Join the components as seen in the fritzing diagram. It's important to remember that your Relay's COM, NO (usually open), and NC (typically Close) contacts could be on opposite sides. Please verify this with a millimetre.
Relays can be found anywhere that electricity is being switched, from a simple traffic light controller to a high-voltage switchyard. Relays, in the broadest sense, are equivalent to any other switch. They can connect or disconnect a circuit and are frequently employed to activate or deactivate an electrical load. However, this is a comprehensive statement; there are many other relays, and each Relay behaves slightly differently depending on the task at hand; as the electromechanical Relay is one of the most widely used relays, we will devote more space to discussing it here. In spite of variations in design, all relays work according to the same fundamental concept, so let's dive into the nuts and bolts of relays and talk about how they function.
A relay is called an electromechanical switch that may either establish or rupture an electrical connection. A relay is like a mechanical switch, except that it is activated and deactivated by an electronic signal rather than by physically flipping a switch. It comprises a flexible movable mechanical portion controlled electrically through an electromagnet. Once again, this Relay operating concept is suitable exclusively for electromechanical relays.
A common and widely used relay consists of electromagnets typically employed as a switch. However, there are many kinds of relays, each with its purpose. When a signal is received on one side of the device, it controls the switching activity on the other, much like the dictionary definition of Relay. That's right, a relay is an electromechanical switch that can open and close circuits. This device's primary function is to establish or sever contact with the aid of a signal to turn it ON or OFF automatically and without human intervention. Its primary use is to allow a low-power signal to exert control over a circuit with a high power consumption. Typically, the high-voltage circuit is controlled by a direct current (DC) signal.
The following diagram depicts the internal structure and design of a Relay.
A coil of copper wire is wound around a core, which is then placed inside a housing. When the coil is electrified, it attracts the movable armature, which is supported by a spring or stand and has a metal contact attached to one end. This assembly is positioned over the core. In most cases, the movable armature is a shared connection point for the motor's internal components and the other wiring harness. The usually closed (NC) pin is linked to the common terminal, while the ordinarily opened (NO) pin is not used in operation. By connecting the armature to the usually open contact whenever the coil is activated, current can flow uninterruptedly through the armature. When the power is turned off, it returns to its starting position.
The picture below shows a schematic of the Relay's circuit in its most basic form.
In the images below, you can see the main components of an electromechanical relay—an electromagnet, a flexible armature, contacts, a yoke, and a spring/frame/stand. They have been thoughtfully placed into a relay.
The workings of a Relay's mechanical components have been outlined below.
Electromagnet
An electromagnet is crucial to the operation of a relay. This metal lacks magnetic properties but can be transformed into a magnet when exposed to an electrical current. It is healthy knowledge that a conductor takes on the magnetic characteristics of the current flowing through it. Thus, a metal can operate as a magnet and attract magnetic objects within its range when wound with a conductive material and powered by an adequate power source.
Movable Armature
A moveable armature is just one piece of metal that can rotate or stand on its own. It facilitates connection-making and -breaking with the contacts attached to it.
Contacts
Internal conductors are the wires that run through a device and hook up to its terminals.
Yoke
It's a tiny metal piece attached to a core that attracts and retains the armature whenever the coil is activated.
Spring (optional)
While some relays can function without a spring, those that do have one attach it to the armature at one end to prevent any snagging or binding. One can use a metal "stand" in place of a spring.
Let's examine the differences between a relay's normally closed and normally open states.
If no current flows through the core, there will be no magnetic field, and the device will not be a magnet. As a result, it is unable to draw in the flexible framework. So, the ordinarily closed position of the armature is the starting point (NC).
When a high enough voltage is supplied to the core, it begins to have a strong magnetic field around itself, allowing it to function as a magnet. The magnetic field produced by the core attracts the movable armature whenever it comes within its field of influence, changing the armature's location. As it has been wired to a normally open relay pin, any external circuits attached to it will no longer operate in the same way.
It is important to connect the relay pins correctly so that the external circuit can do its job. When a coil is powered, the armature is drawn toward it, revealing the switching action; when the power is cut, the coil loses its magnetic property, and the armature returns to its original location. The animation provided below shows the Relay in action.
There is nothing complicated about a transistor, yet there is a lot going on inside it. Okay, so first, we'll tackle the easy stuff. An electronic transistor is a small component that can switch between two functions. It's a switch that can also act as an amplifier.
An amplifier is a device that takes in a little electric current and outputs a significantly larger electric current (called an output current). It can be thought of as a current booster. One of the earliest applications for transistors, this is particularly helpful in devices like hearing aids. A hearing aid contains a microscopic microphone that converts ambient sound into electrical signals. These are then amplified by a transistor and used to power a miniature loudspeaker, which reproduces the ambient noise at a much higher volume.
It is possible to use a transistor as a switch. A transistor is a device that allows for the passage of one electrical current to induce a much larger current to flow through the next part of the device. What this means is that a relatively small current can activate a much larger one. All computer chips function in this general way. As an illustration, a memory chip may have as many as a billion individually controllable transistors. Due to the fact that each transistor can exist in either of two states, it is capable of storing either a zero or a one. A chip's ability to hold billions of zeroes and ones, as well as almost as many regular numbers and letters, is made possible by its billions of transistors.
Diodes can range in size from what's shown in the image up top. They feature a cylindrical body that is usually black with a stripe at one end and certain leads that protrude so that we may plug it into a circuit. The opposite terminal is called the cathode and is opposite the anode.
A diode is an electrical component that restricts current flow in one direction.
To illustrate, picture a swing valve fitted in a water line. The water pressure inside the pipe will force open the swing gate, allowing the water to flow uninterrupted. In contrast, the gate will be forced shut, and water flow will stop if the river alters its course. As a result, there is only one direction for water to flow.
Very much like a diode, which we also employ to alter the current flow through a circuit, it allows us to switch it on and off at will.
We have now animated this process using electron flow, in which electrons move from negative to positive. However, traditional flow, positive to negative, is the norm in electronics engineering. It's usually best to start with the conventional current because it's more familiar to most people, but feel free to use either one; we'll assume you're aware of the difference.
It's important to remember that the light-emitted diode will only light up properly if the diode is connected to the circuit in the correct orientation when adding it to a simple Light emitted diode circuit like the one shown above. Only one direction of current can travel through it. Accordingly, its conductive or insulating properties are determined by the orientation in which it is mounted.
So that it can conduct electricity, you must join the black end to the neutral and the striped end to the positive. The forward bias is the condition in which current can flow. If we invert the diode, it will become an insulator and stop the passage of electricity. The term for this is "the reverse bias."
You probably know that electricity is the transfer of electrons between atoms that are not bound. Because of its high number of unpaired electrons, copper is widely used for electrical wiring. Since rubber is an insulator—its electrons are kept very securely, so they cannot flow between atoms—it is used to wrap around the copper wires for our protection.
In a simplified form of a metal conducting atom, the nucleus is at the center, and the electrons are housed in a series of shells around it. It takes a specific amount of energy for an electron to be absorbed into each shell, and each shell has a max number of electrons it can hold. Those electrons that are furthest from the nucleus are the most energetic. Conductors have between one and three electrons in their outermost "valence" shell.
The nucleus acts as a magnet, keeping the electrons in place. However, there is yet another layer, the conduction band. If an electron gets here, it can leave its atom and travel to another. Because the valence shell and conduction band of a metal atom overlap, the electron can move quickly and easily between the two.
The insulator has a tightly packed outer layer. No free space for electrons to occupy. Because of the strong attraction between the nucleus and the electrons and the great distance between the nucleus and the conduction band, the electrons are trapped inside the nucleus and cannot leave. Because of this, electricity is unable to travel through it.
Of course, a semiconductor is also a different type of material. A semiconductor might be silicon, for instance. This material behaves as an insulator because it has one more electron than is necessary in its outermost shell to be a conductor. However, with enough external energy, a few valence electrons can generate enough momentum to hop across to the conduction band, where they can finally break free. Consequently, this substance can perform the roles of both an insulator and a conductor.
Due to the lack of free electrons in pure silicon, engineers must add a small number of materials (called "doping") to the silicon to alter its electrical properties.
This process gives rise to P-type and N-type doping, respectively. The diode itself is a combination of these doped materials.
Two leads connect the anode and cathode to various thin plates inside the diode. P-Type doped silicon is on the anode side of these plates, and the cathode side is N-Type doped silicon—an insulating and protective resin that coats the entire structure.
Consider the material to be pure silicon before it has been doped. There are four silicon atoms surrounding each one. Because silicon atoms need eight electrons to fill their valence shells but only have four available, they share one with their neighbours. Covalent bonding describes this type of interaction.
Phosphorus, an N-type element, can be substituted for a number of silicon atoms in a compound semiconductor. Phosphorus has a 5-electron valence shell because of this. This extra electron isn't needed because particles are sharing them to reach the magic number of 8. This means there's an extra electrons in the material, and it's free to go wherever it wants.
In P-type doping, a substance like aluminum is introduced. Due to its limited valence electron pool of 3, this atom is unable to share an electron with any of its four neighbours. An electron-sized void is therefore made available.
We now have silicon with either too many or too few electrons, depending on the doping method.
Upon joining, the two substances forge a p-n junction. This is a depletion region, and it forms at the intersection. Here, some of the surplus electrons on the N-type side migrate over to fill the vacancies on the P-type side. By moving in this direction, electrons and holes will accumulate on either side of a barrier. Holes are thought to be positively charged since they are the opposite of electrons, which are negatively charged. The resulting accumulation produces two distinct regions, one slightly negatively charged and the other slightly positively charged. This forms an electric field that blocks the path of any more electrons. In regular diodes, the voltage drop over this area is only 0.7V.
By applying a voltage across the diode with the P-Type anode linked to the positive and the N-Type cathode attached to the negative, a forward bias is established, and current can flow. The electrons can't get over the 0.7V barrier unless the voltage source is higher.
We can achieve this by connecting the positive terminal of the power supply to the cathode of an N-type device and the negative terminal to the anode of a P-type device. The diode functions as a conductor to block current because the barrier expands as holes are drawn toward the negative and electrons are drawn toward the positive.
A resistor is a two-terminal, non-active electrical component that reduces the amount of current in electric and electronic circuits. A certain amount can lower the current by strategically placing a resistor in a circuit. From the outside, most resistors will appear identical. But if you crack it open, you'll find a ceramic rod used for insulation within, with copper wire covering the rest of the structure. Those copper twists are crucial to the resistance. When copper is sliced thinner, resistance rises because electrons have more difficulty penetrating the material. We now know that electrons can move more freely through some conductors than insulators.
George Ohm investigated the correlation between resistor size and material thickness. His proof showed that an object's resistance (R) grows in proportion to its length. Because of this, the resistance offered by the lengthier and thin wires is greater. However, wire thickness has a negative effect on resistance.
Once everything is hooked up, you can start your server by browsing to the IP address of your RPi and entering the port you chose earlier (as mentioned in the previous section), entering your password and username and seeing a page that looks like the one below.
All it takes is a few clicks of your mouse to operate four AC home appliances from afar. This can be controlled from a mobile device (phone, tablet, etc.) and expanded with additional switches and relays. Thank you all for reading to the end.
This guide showed us how to set up a web-based control system for our home automation system based on the Raspberry Pi 4. We have learned how to utilize the WebIOPi API to manage, debug, and use raspberry Pi's GPIO, sensors, and adapters from an internet browser or any application. We have also implemented JavaScript, CSS, and HTML code for the web application. For those who thrive on difficulty, feel free to build upon this base and add whatever demanding module you can think of to the project. The following tutorial will teach you how to use a Raspberry Pi 4 to create a Line Follower robot that can navigate obstacles and drive itself.
Welcome to the next tutorial on our raspberry pi four python programming. In the previous article, we built a system that recognizes when two people are in physical contact using OpenCV and a Raspberry Pi 4. We used the weights from the YOLO version 3 Object Recognition Algorithm to implement the Deep Neural Networks part. Regarding image processing, the Raspberry Pi consistently comes out on top compared to other controllers. A facial recognition program was among the earlier attempts to use Raspberry Pi for sophisticated picture processing. In today's world of cutting-edge technology, digital image processing has expanded rapidly to become an integral feature of many portable electronic gadgets.
Digital image processing is widely used for such tasks as item detection, facial recognition, and people counting. This guide will use a Raspberry Pi 4 and ThingSpeak to create a crowd-counting system based on OpenCV. In this case, we will utilize the pi camera module to take pictures in a continuous loop, and then we will run the images through the Histogram Based Object descriptor to find the things in the photos. Next, we'll compare these images to OpenCV's pre-trained model for facial recognition. The headcount may be seen by anybody, anywhere in the world, because of the public nature of the ThingSpeak channel.
Knowing how many people show up to an event or purchase a newly released product is vital for event management and retail shop owners. Still, it's even more critical that they can use that information to improve future events. To their relief, modern crowd-counting technology has made it simpler for event planners and business owners to acquire actionable data on event attendance that can be used to improve ROI.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry Pi 4
Pi Camera
ThingSpeak
Python3
OpenCV3
In this case, the OpenCV framework will make people count. You must first upgrade your Raspberry Pi before you can install OpenCV.
sudo apt-get update
Then, get OpenCV ready for your Raspberry Pi by installing its prerequisites.
sudo apt-get install libhdf5-dev -y
sudo apt-get install libhdf5-serial-dev –y
sudo apt-get install libatlas-base-dev –y
sudo apt-get install libjasper-dev -y
sudo apt-get install libqtgui4 –y
sudo apt-get install libqt4-test –y
Once that is done, use the following command to install OpenCV on your Raspberry Pi.
pip3 install OpenCV-contrib-python==4.1.0.25
We need to get some additional packages on the Raspberry Pi before we can begin writing the code for the Crowd Counting app.
Installing imutils: To perform basic image processing tasks like translating, rotating, resizing, skeletonizing, and displaying Matplotlib images more efficiently in OpenCV, imutils are used. So, run the following command to set up imutils:
pip3 install imutils
matplotlib: The matplotlib library should then be installed. When it comes to Python visualizations, Matplotlib is your one-stop shop for everything from static to animated to interactive.
pip3 install matplotlib
One of the most widely used IoT platforms, ThingSpeak allows us to keep tabs on our data from any location with an Internet connection. The system can also be controlled remotely by using the Channels and web pages provided by ThingSpeak. You must first register for an account on ThingSpeak to create a channel. If you have a ThingSpeak account, please log in with your username and password.
Select Sign up and fill out the required fields.
Double-check your email address and press the "Next" button when you're done. Now that you're logged in, click the "New Channel" button to make a brand-new channel.
When you're ready to begin uploading information, select "New Channel" and give it a descriptive name and brief explanation. One new field, "People," has been added. Any number of areas may be made, as needed. Then, click the "Save Channel" button after entering the necessary information. You'll need to pass your API and channel ID into a Python script whenever you want to submit data to ThingSpeak.
For this OpenCV people-countering project, all you need is a Raspberry Pi and a Pi camera; to get started, plug the camera's ribbon connector into the Raspberry pi's designated camera slot.
The Pi 4 Camera board is a purpose-built expansion board for the Raspberry Pi computer. The Raspberry Pi hardware is connected via a specialized CSI interface. In its native still-capture mode, the sensor's resolution is 5 megapixels. Capturing at up to 1080p and 30 frames/second in video mode is possible. Because of its portability and compact size, this camera module is fantastic for handheld applications.
A ribbon cable connects the camera board to the Raspberry Pi. Camera PCB and Raspberry Pi hardware are associated with a ribbon cable. If you join the ribbon cables correctly, the camera will work. The camera PCB's blue backing must face away from the PCB, while the Raspberry Pi hardware's blue backing must face the Ethernet port.
One example of a feature descriptor is the HOG, similar to the Canny Edge Detector algorithm. Object detection is a typical application of this technique in image processing and computer vision applications. This method uses a count of gradient orientation occurrences in the limited region of an image. There are a lot of similarities between this approach and Scale Invariant Feature Transformation. The HOG descriptor highlights object structure or form. This method of computing features is superior to other edge descriptors because it considers both the magnitude and the angle of the gradient. Histograms are created for the image's regions based on the gradient's intensity and direction.
First, load the image that will serve as the basis for the HOG feature calculation into the system. Reduce the size of the image to 128 by 64 pixels. The research authors utilized and recommended this dimension because improving detection outcomes for pedestrians was their primary goal. After achieving near-perfect scores on the MIT pedestrian's database, the authors of this study opted to create a new, more difficult dataset: the 'INRIA' dataset (http://pascal.inrialpes.fr/data/human/), which includes 1805 (128x64) photographs of individuals cut from a wide range of personal photos.
In this step, we compute the image's gradient. The gradient can be calculated using the image's magnitude and angle. First, we determine Gx and Gy for every pixel in a 3x3 grid. As a first step, we determine the Gx and Gy values for each pixel by plugging their respective values into the following formulas.
Each pixel's magnitude and angle are computed using the following formulae after Gx and are determined.
Once the gradient for each pixel has been calculated, the resulting gradient matrices are each partitioned into eight 8x8 cells that form a block. Each block is assigned a 9-point histogram. Each bin in a 9-point histogram has a 20-degree range, so the resulting histogram has nine bins total. The numbers in Figure 8 are assigned to a 9-bin histogram graphically depicting the results of the calculations. Each of these 9-point graphs can be represented graphically as a histogram whose bins output the relative strength of the gradient across the corresponding intervals. Since a block can have 64 distinct values, the calculation below is carried out for each of the 64 possible combinations of magnitude and gradient. Because 9-point histograms are being used, therefore:
The following terms will define the limits of each jth bin:
The average value of each bucket will be:
Illustration of a histogram with nine discrete bins. For a particular 8x8 block of 64 cells, there will be only one possible histogram. Each of the sixty-four cells will contribute their Vj and Vj+1 values to the array's indices at the jth and (j+1) positions.
When determining the value assigned to cell j in block I, we first determine which bin j will be assigned to it. The following equations will provide the value:
Each pixel's value, Vj, is calculated and stored in the set at the jth and (j+1)the indexes of the bin that serves as the block's bin. Upon completing the preceding steps, the resulting matrix will have dimensions 16 by eight by 9. When the histograms for all blocks have been computed, a new block is formed by joining together four cells of the 9-by-9 histogram matrix (2x2). This chopping is carried out overlappingly, with an 8-pixel stride. We create a 36-feature vector by concatenating the 9-point histograms of each of the four cells that make up the block.
A combined FBI is created from four blocks by traversing a 2x2 grid around the image.
The L2 norm is used to standardize FB values across blocks.
The value of k for normalization is found by applying the following formulae:
Normalizing is performed to lessen the impact of variations in the contrast between photographs of the same object—each section. Data is collected in the form of a 36-point feature vector. Seven blocks line up across the bottom and fifteen at the top. Therefore, the entire length of all histogram-oriented gradient features will be 3780 (7 x 15 x 36). The image's HOG characteristics are extracted.
HOG features are seen parallelly on a single image with the image library.
This page includes the complete Python code for an OpenCV project that counts the people in a crowd. Here, we break down the code's crucial parts so you can understand them better—first, import all the necessary libraries that will be used later in the code.
import cv2
import imutils
from imutils.object_detection import non_max_suppression
import numpy as np
import requests
import time
import base64
from matplotlib import pyplot as plt
from urllib.request import urlopen
Imutils:
For use with OpenCV and either version of Python, this package provides a set of helper functions for everyday image processing tasks such as scaling, cropping, skeletonizing, showing Matplotlib pictures, grouping contours, identifying edges, and more.
Numpy:
You can manipulate arrays in Python with the help of the NumPy library. Matrix operations, the Fourier transform, and linear algebra are all within their purview. Because it is freely available to the public, anyone can use it. That's why it's called "Numerical Python," or "NumPy" for short.
Python's list data structure can replace arrays, but it could be faster. NumPy's intended benefit is an array object up to 50 times quicker than standard Python lists. To make working with NumPy's array object, ndarray, as simple as possible, the library provides several helpful utilities. Data science makes heavy use of arrays because of the importance placed on speed and efficiency.
Requests:
You should use the requests package if you need to send an HTTP request from Python. It hides the difficulties of requests making behind a lovely, straightforward API, freeing you to focus on the application's interactions with services and data consumption.
Time:
In Python, the time module has a built-in method called local time that may be used to determine the current time in a given location depending on the time in seconds that have passed since the epoch (). tm isdst will range from 0 to 1 to indicate whether or not daylight saving time applies to the current time in the region.
Base64:
If you need to store or transmit binary data over a medium better suited for text, you should look into using a Base64 encoding technique. There is less risk of data corruption or loss thanks to this encoding method. Base64 is widely used for many purposes, such as MIME-enabled email storing complicated data in XML and JSON.
Matplotlib:
When it comes to Python visualizations, Matplotlib is your one-stop shop for everything from static to animated to interactive. Matplotlib facilitates both straightforward and challenging tasks. Design graphs worthy of publication. Create movable, updatable, and zoomable figures.
urllib.request:
If you need to make HTTP requests with Python, you may be directed to the brilliant requests library. Though it's a great library, you may have noticed that it needs to be a built-in part of Python. If you prefer, for whatever reason, to limit your dependencies and stick to standard-library Python, then you can reach for urllib.request!
Then, after the libraries have been imported, you can paste in the channel ID and API key for the ThingSpeak account you previously copied.
channel_id = 812060 # PUT CHANNEL ID HERE
WRITE_API = 'X5AQ3EGIKMBYW31H' # PUT YOUR WRITE KEY HERE
BASE_URL = "https://api.thingspeak.com/update?api_key= {}".format(WRITE_API)
Set the default values for the HOG descriptor. Several other uses have been found for HOG, making it one of the most often implemented methods for object detection. In the past, an OpenCV pre-trained model for people detection could be accessed through cv2.HOGDescriptor getDefaultPeopleDetector().
hog = cv2.HOGDescriptor()
hog.setSVMDetector(cv2.HOGDescriptor_getDefaultPeopleDetector())
Raspberry PI is provided with a three-channel color image inside the detector() function. It then uses imutils to scale the image down to the appropriate size. The SVM classification result is then used to inform the detectMultiScale() method, which examines the image to determine the presence or absence of a human.
def detector(image):
image = imutils.resize(image, width=min(400, image.shape[1]))
clone = image.copy()
rects, weights = hog.detectMultiScale(image, winStride=(4, 4), padding=(8, 8), scale=1.05)
If you're getting false positive results or detection failures due to capture-box overlap, try running the below code, which uses non-max suppressing capability from imutils to activate overlapping regions.
for (x, y, w, h) in rects:
cv2.rectangle(image, (x, y), (x + w, y + h), (0, 0, 255), 2)
rects = np.array([[x, y, x + w, y + h] for (x, y, w, h) in rects])
result = non_max_suppression(rects, probs=None, overlapThresh=0.7)
return result
With the help of OpenCV's VideoCapture() method, the image is retrieved from the Pi camera within the record() function, where it is resized with the imultis before being sent to ThingSpeak.
def record(sample_time=5):
camera = cv2.VideoCapture(0)
frame = imutils.resize(frame, width=min(400, frame.shape[1]))
result = detector(frame.copy())
thingspeakHttp = BASE_URL + "&field1={}".format(result1)
Now that everything is hooked up and ready to go, let's put it through its paces. Launch the program by extracting it to a new folder. You'll need to give Python a few seconds to load all the necessary modules. Start the program. A new window will pop up, showing the camera's output after a few seconds. Make sure your Raspberry Pi camera is operational before running the python script. The following command is used to activate the python script after a review of the camera has been completed:
At that point, a new window will appear with your live video feed inside of it. OpenCV will count the number of persons in the first frame that Pi processes. The appearance of a box will indicate the detection of humans:
Now that you know how many people are expected to show up, you can check the crowd size from the comfort of your own home via your ThingSpeak channel.
You can now efficiently conduct crowd counts with OpenCV and a Raspberry Pi. This technology helps with guaranteeing the safety of those attending large-scale events, which is a top priority for event planners. Knowing how people will flow through a venue or store is crucial for offering effective crowd management services. It will also improve efficiency and customer service because it is helpful for event and store managers to track the number of people entering and leaving their establishments at any one time. Additionally, it is important for event planners to understand dwell time in order to ascertain which parts of the venue are popular with attendees and which are completely bypassed. This gives them information about how the guest felt, which lets them better use the space they have.
import cv2
import imutils
from imutils.object_detection import non_max_suppression
import numpy as np
import requests
import time
import base64
from matplotlib import pyplot as plt
from urllib.request import urlopen
channel_id = 812060 # PUT CHANNEL ID HERE
WRITE_API = 'X5AQ3EGIKMBYW31H' # PUT YOUR WRITE KEY HERE
BASE_URL = "https://api.thingspeak.com/update?api_key={}".format(WRITE_API)
hog = cv2.HOGDescriptor()
hog.setSVMDetector(cv2.HOGDescriptor_getDefaultPeopleDetector())
# In[3]:
def detector(image):
image = imutils.resize(image, width=min(400, image.shape[1]))
clone = image.copy()
rects, weights = hog.detectMultiScale(image, winStride=(4, 4), padding=(8, 8), scale=1.05)
for (x, y, w, h) in rects:
cv2.rectangle(image, (x, y), (x + w, y + h), (0, 0, 255), 2)
rects = np.array([[x, y, x + w, y + h] for (x, y, w, h) in rects])
result = non_max_suppression(rects, probs=None, overlapThresh=0.7)
return result
def record(sample_time=5):
print("recording")
camera = cv2.VideoCapture(0)
init = time.time()
# ubidots sample limit
if sample_time < 3:
sample_time = 1
while(True):
print("cap frames")
ret, frame = camera.read()
frame = imutils.resize(frame, width=min(400, frame.shape[1]))
result = detector(frame.copy())
result1 = len(result)
print (result1)
for (xA, yA, xB, yB) in result:
cv2.rectangle(frame, (xA, yA), (xB, yB), (0, 255, 0), 2)
plt.imshow(frame)
plt.show()
# sends results
if time.time() - init >= sample_time:
thingspeakHttp = BASE_URL + "&field1={}".format(result1)
print(thingspeakHttp)
conn = urlopen(thingspeakHttp)
print("sending result")
init = time.time()
camera.release()
cv2.destroyAllWindows()
# In[7]:
def main():
record()
# In[8]:
if __name__ == '__main__':
main()
Crowd dynamics can be affected by several things, such as the passage of time, the layout of the venue, the amount of information provided to visitors, and the overall enthusiasm of the gathering. Managers of large crowds need to be flexible and responsive in case of sudden changes in the environment that affect the situation's dynamics in real-time. Trampling events, mob crushes, and acts of violence can break out without proper crowd management.
The complexity and uncertainty of large-scale events emphasize the importance of providing timely, relevant information to crowd managers. Occupancy control technology helps event planners anticipate how many people will show up to their event, so they can prepare appropriately by ensuring adequate security guards, exits, etc.
Using Raspberry Pi and some smart subtractions and blob tracking, this article describes a system for counting individuals. We show how many people have entered and left a building. The principles of HOG and the calculation of features have also been covered. The testing outcomes demonstrate the viability of using this raspberry pi based device as an essential people-counting station. In the following tutorial, we'll learn how to assemble an intelligent energy monitor based on the Internet of Things and a Raspberry Pi 4.
During the era of Covid-19, social distancing has proven to be an efficient method of reducing the spread of contagious viruses. It is recommended that people avoid close contact as much as possible because of the potential for disease transmission. Many public spaces, including workplaces, banks, bus terminals, train stations, etc., struggle with the issue of keeping a safe distance.
The previous guide covered the steps necessary to connect the PCF8591 ADC/DAC Analog Digital Converter Module to a Raspberry Pi 4. On our Terminal, we saw the results displayed as integers. We dug deeper into the topic, figuring out exactly how the ADC produces its output signals. In this article, however, we will use OpenCV and a Raspberry Pi to create a system that can detect when people are trying to avoid eye contact with one another. We will employ the YOLO version 3 Object Recognition Algorithm's weights to implement the Deep Neural Networks component. Compared to other controllers, the Raspberry Pi always comes out as the best option for image processing tasks. Previous efforts utilizing Raspberry Pi for advanced image processing included a face recognition application.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Jumper Wires | Amazon | Buy Now | |
| 2 | PCF8591 | Amazon | Buy Now | |
| 3 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry Pi 4
Only a Raspberry pi 4 having OpenCV pre-installed will do for this purpose. Digital image processing is handled with OpenCV. Digital Image Processing is often used for people counting, facial identification, and detecting objects in images.
The savvy YOLO (You Only Look Once) Convolution neural networks (CNN) in real-time Object Detection are invaluable. The most recent version of YOLO, YOLOv3, is a fast and accurate object identification algorithm that can identify eighty distinct types of objects in both still and moving media. The algorithm first runs a unique neural net over the entire image before breaking it up into areas and computing border boxes and probability for each. The YOLO base model has a 45 fps real-time frame rate for processing photos. Compared to other detection approaches, such as SSD and R-CNN, the YOLO model is superior.
In the past, computers relied on input devices like keyboards and mice; today, they can also analyze data from visual sources like photos and videos. Computer Vision is a computer's (or a machine's) capacity to read and interpret graphic data. Computing vision has advanced to the point that it can now evaluate the nature of people and objects and even read their emotions. This is feasible because of deep learning and artificial intelligence, which allow an algorithm to learn from examples like recognizing relevant features in an unlabeled image. The technology has matured to the point where it can be employed in critical infrastructure protection, hotel management, and online banking payment portals.
OpenCV is the most widely used computer vision library. It is a free and open-source Intel cross-platform library that may be used with any OS, including Windows, Mac OS X, and Linux. This will make it possible for OpenCV to function on a mobile device like a Pi, which will have a wide range of applications. Let's dive in, then.
OpenCV and its prerequisites won't run without updating the Raspberry Pi to the latest version. To install the most recent software for your Raspberry Pi, type in the following commands:
sudo apt-get update
Then, use the scripts below to set up the prerequisites on your RPi so you can install OpenCV.
sudo apt-get install libhdf5-dev -y
sudo apt-get install libhdf5-serial-dev –y
sudo apt-get install libatlas-base-dev –y
sudo apt-get install libjasper-dev -y
sudo apt-get install libqtgui4 –y
sudo apt-get install libqt4-test –y
Finally, run the following lines to install OpenCV on your Raspberry Pi.
pip3 install OpenCV-contrib-python==4.1.0.25
OpenCV's installation on a Raspberry Pi can be nerve-wracking because it takes a long time, and there's a good possibility you'll make a mistake. Given my own experiences with this, I've tried to make this lesson as straightforward and helpful as possible so that you won't have to go through the same things I did. Even though OpenCV 4.0.1 had been out for three months when I started writing this lesson, I decided to use the older version (4.0.0) because of some issues with compiling the newer version.
This approach involves retrieving OpenCV's source package and compiling it on a Raspberry Pi with the help of CMake. Installing OpenCV in a virtual environment allows users to run many versions of Python and OpenCV on the same computer. But I'm not going to do that since I'd rather keep this essay brief and because I don't anticipate that it will be required any time soon.
Step 1: Before we get started, let's ensure that our system is up to date by executing the command below:
sudo apt-get update && sudo apt-get upgrade
If there are updated packages, they should be downloaded and installed automatically. There is a 15-20 minute wait time for the process to complete.
Step 2: We must now update the apt-get package to download CMake.
sudo apt-get update
Step 3: When we've finished updating apt-get, we can use the following command to retrieve the CMake package and put it in place on our machine.
sudo apt-get install build-essential cmake unzip pkg-config
When installing CMake, your screen should look similar to the one below.
Step 4: Then, use the following command to set up Python 3's development headers:
sudo apt-get install python3-dev
Since it was pre-installed on mine, the screen looks like this.
Step 5: The following action would be to obtain the OpenCV archive from GitHub. Here's the command you may use to replicate the effect:
wget -O opencv.zip https://github.com/opencv/opencv/archive/4.0.0.zip
You can see that we are collecting version 4.0.0 right now.
Step 6: The OpenCV contrib contains various python pre-built packages that will make our development efforts more efficient. Therefore, let's also download that with the command that is identical to the one shown below.
wget -O opencv_contrib.zip https://github.com/opencv/opencv_contrib/archive/4.0.0.zip
The "OpenCV-4.0.0" and "OpenCV-contrib-4.0.0" zip files should now be in your home directory. If you need to know for sure, you may always go ahead and check it out.
Step 7: Let's extract OpenCV-4.0.0 from its.zip archive with the following command.
unzip opencv.zip
Step 8: Extraction of OpenCV contrib-4.0.0 via the command line is identical.
unzip opencv_contrib.zip
Step 9: OpenCV cannot function without NumPy. Follow the command below to begin the installation.
pip install numpy
Step 10: In our new setup, the home directory would now contain two folders: OpenCV-4.0.0 and OpenCV contrib-4.0.0. Next, we'll make a new directory inside OpenCV-4.0.0 named "build" to perform the actual compilation of the Opencv library. The steps needed to achieve the same result are detailed below.
cd~/opencv
mkdir build
cd build
Step 11: OpenCV's CMake process must now be initiated. In this section, we specify the requirements for compiling OpenCV. Verify that "/OpenCV-4.0.0/build" is in your path. Then, paste the lines below into the Terminal.
cmake -D CMAKE_BUILD_TYPE=RELEASE \
-D CMAKE_INSTALL_PREFIX=/usr/local \
-D OPENCV_EXTRA_MODULES_PATH=~/opencv_contrib-4.0.0/modules \
-D ENABLE_NEON=ON \
-D ENABLE_VFPV3=ON \
-D BUILD_TESTS=OFF \
-D WITH_TBB=OFF \
-D INSTALL_PYTHON_EXAMPLES=OFF \
-D BUILD_EXAMPLES=OFF ..
Hopefully, the configuration will proceed without a hitch, and you'll see "Configuring done" and "Generating done" in the output.
If you encounter an issue during this procedure, check to see if the correct path was entered and if the "OpenCV-4.0.0" and "OpenCV contrib-4.0.0" directories exist in the root directory path.
Step 12: This is the most comprehensive process that needs to be completed. Using the following command, you can compile OpenCV, but only if you are in the "/OpenCV-4.0.0/build" directory.
Make –j4
Using this method, you may initiate the OpenCV compilation process and view the status in percentage terms as it unfolds. After three to four hours, you will see a completed build screen.
The command "make -j4" utilizes all four processor cores when compiling OpenCV. Some people may feel impatient waiting for a 99% success rate, but eventually, it will be worth it.
After waiting an hour, I had to cancel the process and rebuild it with "make -j1," which did the trick. It is advisable first to use make j4 since that will utilize all four of pi's cores, and then use make j1, as make j4 will complete most of the compilation.
Step 13: If you are at this point, congratulations. You have made it through the entire procedure with flying colors. The final action is to run the following command to install libopecv.
sudo apt-get install libopencv-dev python-OpenCV
Step 14: Finally, a little python script can be run to verify that the library was successfully installed. Try "import cv2" in Python, as demonstrated below. You shouldn't get any error message when you do this.
Let's get the necessary packages set up on the Raspberry Pi before we begin writing the code for the social distance detector.
utils are designed to simplify the use of OpenCV for standard image processing tasks like translating, rotating, resizing, skeletonizing, and presenting pictures via Matplotlib. If you want to get the imutils, type in the following command:
pip3 install imutils
The complete code may be found at the bottom of the page. In this section, we'll walk you through the most crucial parts of the code so you can understand it better. All the necessary libraries for this project should be imported at the beginning of the code.
import numpy as np
import cv2
import imutils
import os
import time
Distances between objects or points in a video frame can be determined with the Check() function. The two things in the picture are represented by the a and b points. The Euclidean distance is determined using these two positions as the starting and ending points.
def Check(a, b):
dist = ((a[0] - b[0]) ** 2 + 550 / ((a[1] + b[1]) / 2) * (a[1] - b[1]) ** 2) ** 0.5
calibration = (a[1] + b[1]) / 2
if 0 < dist < 0.25 * calibration:
return True
else:
return False
The YOLO weights, configuration file, and COCO names file all have specific locations that can be set in the setup function. The os.path module is everything you need to do ordinary things with pathnames. The os.path.join() sub-module intelligently combines two or more path components. cv2.dnn.read The net is reloaded with the saved weights using the netfromdarknet() function. Once the weights have been loaded, the network layers can be extracted using the getLayerNames model.
def Setup(yolo):
global neural_net, ln, LABELS
weights = os.path.sep.join([yolo, "yolov3.weights"])
config = os.path.sep.join([yolo, "yolov3.cfg"])
labelsPath = os.path.sep.join([yolo, "coco.names"])
LABELS = open(labelsPath).read().strip().split("\n")
neural_net = cv2.dnn.readNetFromDarknet(config, weights)
ln = neural_net.getLayerNames()
ln = [ln[i[0] - 1] for i in neural_net.getUnconnectedOutLayers()]
In the image processing section, we extract a still image from the video and analyze it to find the distance between the people in the crowd. The function's first two lines specify an empty string for both the width and height of the video frame. To process many images simultaneously, we utilized the cv2.dnn.blobFromImage() method in the following line. The blob function adjusts a frame's Mean, Scale, and Channel.
(H, W) = (None, None)
frame = image.copy()
if W is None or H is None:
(H, W) = frame.shape[:2]
blob = cv2.dnn.blobFromImage(frame, 1 / 255.0, (416, 416), swapRB=True, crop=False)
neural_net.setInput(blob)
starttime = time.time()
layerOutputs = neural_net.forward(ln)
YOLO's layer outputs are numerical values. With these numbers, we may determine which objects belong to which classes with greater precision. To identify persons, we iterate over all layerOutputs and assign the "person" class label to each. Each detection generates a bounding box whose output includes the coordinates of the detection's center on X and Y as well as its width and height.
scores = detection[5:]
maxi_class = np.argmax(scores)
confidence = scores[maxi_class]
if LABELS[maxi_class] == "person":
if confidence > 0.5:
box = detection[0:4] * np.array([W, H, W, H])
(centerX, centerY, width, height) = box.astype("int")
x = int(centerX - (width / 2))
y = int(centerY - (height / 2))
outline.append([x, y, int(width), int(height)])
confidences.append(float(confidence))
Then, determine how far apart the middle of the active box is from the centers of all other boxes. If the rectangles overlap only a little, set the value to "true."
for i in range(len(center)):
for j in range(len(center)):
close = Check(center[i], center[j])
if close:
pairs.append([center[i], center[j]])
status[i] = True
status[j] = True
index = 0
In the following lines, we'll use the model's box dimensions to create a square around the individual and evaluate whether or not they are in a secure area. If there is little space between the boxes, the box's color will be red; otherwise, it will be green.
(x, y) = (outline[i][0], outline[i][1])
(w, h) = (outline[i][2], outline[i][3])
if status[index] == True:
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 150), 2)
elif status[index] == False:
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)
Now we're inside the iteration function, where we're reading each film frame and analyzing it to determine how far apart the people are.
ret, frame = cap.read()
if not ret:
break
current_img = frame.copy()
current_img = imutils.resize(current_img, width=480)
video = current_img.shape
frameno += 1
if(frameno%2 == 0 or frameno == 1):
Setup(yolo)
ImageProcess(current_img)
Frame = processedImg
In the following lines, we'll utilize the opname-defined cv2.VideoWriter() function to save the output video to the provided place.
if create is None:
fourcc = cv2.VideoWriter_fourcc(*'XVID')
create = cv2.VideoWriter(opname, fourcc, 30, (Frame.shape[1], Frame.shape[0]), True)
create.write(Frame)
When satisfied with your code, launch a terminal on your Pi and go to the directory where you kept it. The following folder structure is recommended for storing the code, Yolo framework, and demonstration video.
The yoloV3 directory is downloadable from the;
https://pjreddie.com/media/files/yolov3.weights
videos from:
https://www.pexels.com/search/videos/pedestrians/
Finally, paste the Python scripts provided below into the same folder as the one displayed above. The following command must be run once you've entered the project directory:
python3 detector.py
I applied this code to a sample video I found on pexels, and the results were interesting. The frame rate was terrible, and the film played back in almost 11 minutes.
Changing line 98 from cv2.VideoCapture(input) to cv2.VideoCapture(0) allows you to test the code without needing a video. Follow these steps to utilize OpenCV on a Raspberry Pi to identify inappropriate social distances.
import numpy as np
import cv2
import imutils
import os
import time
def Check(a, b):
dist = ((a[0] - b[0]) ** 2 + 550 / ((a[1] + b[1]) / 2) * (a[1] - b[1]) ** 2) ** 0.5
calibration = (a[1] + b[1]) / 2
if 0 < dist < 0.25 * calibration:
return True
else:
return False
def Setup(yolo):
global net, ln, LABELS
weights = os.path.sep.join([yolo, "yolov3.weights"])
config = os.path.sep.join([yolo, "yolov3.cfg"])
labelsPath = os.path.sep.join([yolo, "coco.names"])
LABELS = open(labelsPath).read().strip().split("\n")
net = cv2.dnn.readNetFromDarknet(config, weights)
ln = net.getLayerNames()
ln = [ln[i[0] - 1] for i in net.getUnconnectedOutLayers()]
def ImageProcess(image):
global processedImg
(H, W) = (None, None)
frame = image.copy()
if W is None or H is None:
(H, W) = frame.shape[:2]
blob = cv2.dnn.blobFromImage(frame, 1 / 255.0, (416, 416), swapRB=True, crop=False)
net.setInput(blob)
starttime = time.time()
layerOutputs = net.forward(ln)
stoptime = time.time()
print("Video is Getting Processed at {:.4f} seconds per frame".format((stoptime-starttime)))
confidences = []
outline = []
for output in layerOutputs:
for detection in output:
scores = detection[5:]
maxi_class = np.argmax(scores)
confidence = scores[maxi_class]
if LABELS[maxi_class] == "person":
if confidence > 0.5:
box = detection[0:4] * np.array([W, H, W, H])
(centerX, centerY, width, height) = box.astype("int")
x = int(centerX - (width / 2))
y = int(centerY - (height / 2))
outline.append([x, y, int(width), int(height)])
confidences.append(float(confidence))
box_line = cv2.dnn.NMSBoxes(outline, confidences, 0.5, 0.3)
if len(box_line) > 0:
flat_box = box_line.flatten()
pairs = []
center = []
status = []
for i in flat_box:
(x, y) = (outline[i][0], outline[i][1])
(w, h) = (outline[i][2], outline[i][3])
center.append([int(x + w / 2), int(y + h / 2)])
status.append(False)
for i in range(len(center)):
for j in range(len(center)):
close = Check(center[i], center[j])
if close:
pairs.append([center[i], center[j]])
status[i] = True
status[j] = True
index = 0
for i in flat_box:
(x, y) = (outline[i][0], outline[i][1])
(w, h) = (outline[i][2], outline[i][3])
if status[index] == True:
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 0, 150), 2)
elif status[index] == False:
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)
index += 1
for h in pairs:
cv2.line(frame, tuple(h[0]), tuple(h[1]), (0, 0, 255), 2)
processedImg = frame.copy()
create = None
frameno = 0
filename = "newVideo.mp4"
yolo = "yolov3/"
opname = "output2.avi"
cap = cv2.VideoCapture(filename)
time1 = time.time()
while(True):
ret, frame = cap.read()
if not ret:
break
current_img = frame.copy()
current_img = imutils.resize(current_img, width=480)
video = current_img.shape
frameno += 1
if(frameno%2 == 0 or frameno == 1):
Setup(yolo)
ImageProcess(current_img)
Frame = processedImg
cv2.imshow("Image", Frame)
if create is None:
fourcc = cv2.VideoWriter_fourcc(*'XVID')
create = cv2.VideoWriter(opname, fourcc, 30, (Frame.shape[1], Frame.shape[0]), True)
create.write(Frame)
if cv2.waitKey(1) & 0xFF == ord('s'):
break
time2 = time.time()
print("Completed. Total Time Taken: {} minutes".format((time2-time1)/60))
cap.release()
cv2.destroyAllWindows()
Convincing Workers
Since 41% of workers won't return to their desks until they feel comfortable, installing social distancing detection is an excellent approach to reassure them that the situation has been rectified. People without fevers can still be contagious; hence this solution is preferable to thermal imaging cameras.
Space Utilization
Using the detection program, you can find out which places in the workplace are the most popular. As a result, you'll have all the information you need to implement the best precautions.
The Practice of Keeping Tabs and Taking Measures
The software can also be connected to security video systems outside the workplace, such as in a factory where workers are frequently close to one another. To be able to keep an eye on the office atmosphere and single out those whose personal space is too close to others.
Tracking the Queues
Queue monitoring is a valuable addition to security cameras for businesses in retail, healthcare, and other sectors, where waiting in line is unnecessary. As a result, the cameras will be able to monitor and recognize whether or not people are following the social distance requirements. The system can be configured to function with automatic barricades and digital billboards to provide real-time alerts and health and security information.
The adverse effects of social isolation include the following:
Its efficacy decreases when mosquitoes, infected food or water, or other vectors are predominantly responsible for spreading disease.
If a person isn't used to being in a social setting, they may become lonely and depressed.
Productivity drops, and other benefits of interacting with other people are lost.
This tutorial showed us how to build a social distance detection system. This technology makes use of AI and deep learning to analyze visual data. Incorporating computer vision allows for accurate distance calculations between people. A red box will appear around any group that violates the minimum acceptable threshold value. The system's designers used previously shot footage of a busy roadway to build their algorithm. The system can determine an approximation of the distance between individuals. In social interactions, there are two types of space between people: the "Safe" and "Unsafe" distances. In addition, it shows labels according to item detection and classification. The classifier may be utilized to create real-time applications and put into practice live video streams. During pandemics, this technology can be combined with CCTV to keep an eye on the public. Since it is practical to conduct such screening of the mass population, they are routinely implemented in high-traffic areas such as airports, bus terminals, markets, streets, shopping mall entrances, campuses, and even workplaces and restaurants. Keeping an eye on the distance between two people allows us to ensure sufficient space is maintained between them.
Welcome back to another Python tutorial for the Raspberry Pi 4! The previous tutorial showed us how to construct a Raspberry Pi-powered cell phone with a microphone and speaker for making and receiving calls and reading text messages (SMS). To make our Raspberry Pi 4 into a fully functional smartphone, we built software in Python. As we monitored text and phone calls being sent and received between the raspberry pi and our mobile phone, we experienced no technical difficulties. But in this tutorial, you'll learn how to hook up the PCF8591 ADC/DAC module to a Raspberry Pi 4.
Since most sensors only output their data in analog values, converting them to binary values that a microcontroller can understand is a crucial part of any integrated electronics project. A microcontroller's ability to process analog data necessitates using an analog-to-digital converter.
Some microcontrollers, including the Arduino, MSP430, and PIC16F877A, contain an onboard analog-to-digital converter (ADC), whereas others, like the 8051 and Raspberry Pi, do not.
| Where To Buy? | ||||
|---|---|---|---|---|
| No. | Components | Distributor | Link To Buy | |
| 1 | Jumper Wires | Amazon | Buy Now | |
| 2 | PCF8591 | Amazon | Buy Now | |
| 3 | Raspberry Pi 4 | Amazon | Buy Now | |
Raspberry-pi 4
PCF8591 ADC Module
100K Pot
Jumper wires
You are expected to have a Raspberry Pi 4 with the most recent version of Raspbian OS installed on it, and that you are familiar with using a terminal program like putty to connect to the Pi via the Internet and access its file system remotely. Those unfamiliar with Raspberry Pi can learn the basics by reading the articles below.
Each of the ten pins on the PCF8591 module may read analog values as high as 256 on the PCF8591's digital side or vice versa. The board has a thermistor and LDR circuit. Input and output from this module are both analogs. To facilitate the I2C protocol, it has a dedicated serial clock and serial data address pins. The supply voltage ranges from 2.5 to 6V, and the stand-by current is minimal. We can further turn the module's potentiometer knob to control the input voltage. A total of three jumpers can be found on the board. Switching between the thermistor, LDR/photoresistor, and adjustable voltage access circuits is possible by connecting J4, J5, and J6. D1 and D2 are two LEDs on the board, with D1 displaying the strength of the output voltage and D2 indicating the power of the supply voltage. When the supply or output voltage is increased, the brightness of LEDs D1 and D2 are correspondingly enhanced. Potentiometers connected to the LEDs' VCC or AOUT pins also allow testing.
Microprocessors, Arduinos, Raspberry Pis, and other digital logic circuits can interact with the physical environment thanks to Analogue-to-Digital Converters (ADCs). Many digital systems gather information about their settings by analyzing the analog signals produced by transducers such as microphones, light detectors, thermometers, and accelerometers. These signals constantly vary in value since they are derived from the physical world.
Digital circuits use binary signals, which can only be in one of two states, "1" (HIGH) or "0" (LOW), as opposed to the infinitely variable voltage values provided by analog signals (LOW). Therefore, Analogue-to-Digital Converters (A/D) is an essential electronic circuit for translating between constantly varying analog impulses and discrete digital signals.
To put it simply, an analog-to-digital converter (ADC) is a device that, given a single instantaneous reading of an analog voltage, generates a unique digital output code that stands in for that reading. The precision of an A/D converter determines how many binary digits, or bits, are utilized to represent the original analog voltage value.
By rotating the potentiometer's wiper terminal between 0 and VMAX, we may see a continuous output signal with an endless set of output values related to the wiper position. In a potentiometer, the output voltage constantly varies while the wiper is moved between fixed positions. Variations in temperature, pressure, liquid levels, and brightness are all examples of analog signals.
A digital circuit uses a single rotary switch to control the potential divider network, taking the place of the potentiometer's wiper at each node. The output voltage, VOUT, rapidly transitions from one node to the next as the switch is turned, with each node's value representing a multiple of 1.0 volts.
The output is guaranteed at 2-volt, 3-volt, 5 volts, etc., but NOT a 2.5-volt, 3.1-volt, or 4.6-volt output. Using a multi-position switch and more resistive components in the voltage-divider network, resulting in more discrete switching steps, would allow for generating finer output voltage levels.
By this definition, we can see that a digital signal has discrete (step-by-step) values, while an analog signal's values change continuously over time. We are going from "LOW" to "HIGH" or "HIGH" to "LOW."
So the question becomes how to transform an infinitely variable signal into one with discrete values or steps that a digital circuit can work with.
Although several commercially available analog-to-digital converter (ADC) chips exist, such as the ADC08xx family, for converting analog voltage signals to their digital equivalents, a primary ADC can be constructed out of discrete components.
Using comparators to detect various voltage levels and output their switching signal state to an encoder is a straightforward method known as parallel encoding, flash encoding, simultaneous encoding, or multiple comparator converters.
The equivalence output script for a given n-bit resolution is formed by a chain network of accuracy resistors and a series of comparators that are connected but equally spaced.
As soon as an analog signal is provided to the comparator input, it is evaluated with a reference voltage, making parallel converters advantageous because of their ease of construction and lack of need for timing clocks. The following comparator circuit may be of interest.
The LM339N is an analog comparator that compares the relative magnitudes of two voltage levels via its two analog inputs (one positive and one negative).
The comparator receives two signals, one representing the input voltage (VIN) and the other representing the reference value (VREF). The comparator's digital circuits state, "1" or "0," is determined by comparing two output voltages at the input of the comparator.
One input (VREF) receives a reference voltage, and the other input (VIN) receives the input voltage to be compared to it. Output is "OFF" by an LM339 comparator when the input power is lower than (VIN VREF) and "ON" when the input power is higher than the standard voltage (VIN > VREF). A comparator is a device to determine which of two voltages is greater.
Using the potential divider network established by R1 and R2, we can calculate VREF. If the two resistors are identical in value (R1 = R2), then the reference voltage will be half the input power (V/2). Therefore, like with a 1-bit ADC, the output of an open-collector comparator is HIGH if VIN is lower than V/2 and LOW otherwise.
However, by increasing the number of resistors in the voltage divider circuit, we can "divide" the voltage source by an amount equal to the ratio of the resistors' resistances. However, the number of comparators needed increases with the number of resistors in the voltage-divider network.
For an "n"-bit binary output, where "n" is commonly between 8 and 16 bits, a 2n- 1 comparator would be needed in general. As we saw previously, the comparator utilized by the one-bit ADC to determine whether or not VIN was more significant than the V/2 voltage output was 21 minus 1, which equals 1.
If we want to build a 2-bit ADC, we'll need 22-1 or "3" comparators since the 4-to-2-bit encoder circuitry depicted above requires four distinct voltage levels to represent the four digital values.
Where X is a "don't care" statement, representing a logical 0 or 1.
Explain how this analog-to-digital device operates. An analog-to-digital converter (A/D) must generate a faithful digital copy of the Analog input signal to be of any value. To keep things straightforward, we've assumed that VIN is somewhere between 0 and 4 volts and have adjusted VREF and the voltage divider network so that there is a 1 V drop between each resistor in this simple 2-bit Analog - to - digital example.
A binary zero (00) is output by the encoder on pins Q0 and Q1 when the input voltage, VIN, is less than the reference voltage level, which occurs when VIN is between 0 and 1 volts (1V). Since comparator U1's reference voltage input is set to 1 volt, when VIN rises above 1 volt but is below 2 volts, U1's HIGH output is triggered. When the input changes at D1, the priority encoder, used for the 4-to-2-bit encoding, generates a binary result of "1." (01).
Remember that the inputs of a Priority Encoder, like the TTL 74LS148, are all assigned different priority levels. The highest priority input is always used as the output of the priority encoder. So, when a higher priority input is available, lesser priority inputs are disregarded. Therefore, if there are many inputs simultaneously at logic state "1", only the input with high priority will have its output code reflected on D0 and D1.
Thus, now that VIN is greater than 2 volts—the next reference voltage level—comparator U2 will sense the difference and output HIGH. However, when VIN is more than 3 volts, the priority encoder will output a binary "3" (11), as input D2 has a high priority than inputs D0 and D1. Each comparator outputs a HIGH or LOW state to the encoder, generating 2-bit binary data between 00 and 11 as VIN decreases or changes between every reference voltage level.
This is great and all, but commercially available priority encoders, like the TTL, are 8-bit circuits, and if we use one of these, six of the binary numbers will go unused. A digital Ex-OR gate and a grid of signaling diodes can create a straightforward encoder circuit.
Before feeding the diodes, the results of the comparators go through an Exclusive-OR gate to be encoded. Whenever the diode is reverse biased, an external pull-down resistor is connected between the diodes' outputs and ground (0V) to maintain a LOW state and prevent the outputs from floating.
Also, as with the main board, the value of VIN controls which comparator sends a HIGH (or LOW) signal to the exclusive-OR gates, which provide a HIGH output if either of the inputs is HIGH but not both (the corresponding Boolean is Q = A.B + A.B). The AND-OR-NAND gates of combinational logic could also be used to build these Ex-OR gates.
The difficulty with both of these 4-to-2 converter designs is that the input analog voltage at VIN needs to vary by one full volt for the encoder to vary its output code, limiting the precision of the simple two-bit A/D converter to 1 volt. The output resolution can be improved by employing more comparators to convert to a three-bit A/D converter.
The aforementioned parallel ADC takes a voltage reading between 0 and over 3 volts as an analog input and turns it into a binary code with only 2 bits. Since there are 23 = 8 possible digital outputs from a 3-bit digital circuits system, the input analog voltage can be compared to a scale of eight voltages, each of which is one-eighth (1/8) of the voltage supply. This means that we can now measure to an accuracy of 0.5 (4/8) volts and that 23-1 comparators are needed to generate a binary code with a 3-bit resolution (from 000 (0) to 111 (7)).
This will provide us with a three-bit code for each of the eight potential values of the analog input of:
An "X" may be a logic 0 or a logic 1 to indicate a "don't care" state.
Then we can see that more comparators and power levels are required and more output binary bits when the ADC's resolution is increased.
Therefore, an analog-to-digital converter with a 4-bit resolution needs only 15 (24-1) comparators. An eight-bit resolution requires 255 (28-1) comparators. A 10-bit resolution needs 1023 comparators, etc. Therefore, the complexity of this type of Analog-to-Digital Converter circuit increases as the number of output bits increases.
Only if a few binary bits are needed to make a read on a display unit to represent the reference voltage of an input analog signal can a parallel or flashed A/D converter quickly be developed as part of a project due to its fast real-time conversion rate.
As an input interface circuit component, an analog signal from sensors or transducers is converted into a digital binary code by an analog-to-digital converter. Similarly, a digital binary code can be converted into a comparable analog quantity using a Digital-to-Analog Conversion for output interfacing to operate a motor or actuator or, more often, in audio applications.
Knowing the Raspberry Pi's I2C port pins and setting up the I2C connection in the pi 4 are the initial steps in using a PCF8591 with the Pi.
GPIO2 and GPIO3 on the Rpi Model are utilized for I2C communication in this guide.
Raspberry Pi I2C Configuration
Raspberry Pi lacks I2C support by default. Therefore, it must be activated before anything else. Turn on Raspberry Pi's I2C port.
First, open a terminal and enter sudo raspi-config.
The RPi 4 Software Configuration Tool has opened.
Third, activate the I2C by selecting Interfacing options.
Restart the Pi after enabling I2C.
The Raspberry Pi has to know the I2C address of the PCF8591 IC before communication can begin. You may get the address by linking the PCF8591's SDA and SCL pins to the Raspberry Pi's own SDA and SCL jacks. The 5-volts and GND pins should be connected as well.
You may find the address of an attached I2C device by opening a terminal and entering the following command.
sudo i2cdetect –y 1 or sudo i2cdetect –y 0
After locating the I2C address, the next step is constructing the circuit and setting up the required libraries to use PCF8591 and a Raspberry Pi 4.
The circuit diagram to interface the PCF8591 with the Raspberry Pi is straightforward. In this example of interfacing, we'll read the analog signal from any analog inputs and display them in the Raspberry Pi terminal. We have a 100K pot to adjust the settings.
Pi's GPIO2 and GPIO must be connected to the power supply and ground. Then, hook up GPIO3 and GPIO5 to SDA and SCL, respectively. Last but not least, link AIN0 to a 100K pot. Instead of using the Terminal to view the ADC values, a 16x2 LCD can be added.
The complete code and demo video are included after this guide.
To communicate with the I2C bus, you must first import the SMBus library and then use the time library to specify how long to wait before outputting the value.
import smbus
import time
Create some variables now. The I2C bus address is stored in the first variable, and the first analog input pin's address is stored in the second variable.
address = 0x48
A0 = 0x40
Next, we've invoked the library smbus's SMBus(1) function to create an object.
bus = smbus.SMBus(1)
The first line in the while instructs IC to take a reading from the first analog signal pin. Address information read from an Analog pin is saved as a numeric variable in the second line. Exit with the value printed.
While True:
bus.write_byte(address,A0)
value = bus.read_byte(address)
print(value)
time.sleep(0.1)
Finally, put the Python script in a file ending in.py and run it in the Raspberry Pi terminal with the command below.
python filename.py
Ensure that the I2C communication is turned on and that the pins are linked according to the diagram before running the code, or else you will get errors. It's time for the analog readings to appear in the terminal format below. The values gradually shift as you turn the pot's knob. Find out more about getting the software to work in
Here is the full Python script.
import smbus
import time
address = 0x48
bus = smbus.SMBus(1)
while True:
bus.write_byte(address,A0)
value = bus.read_byte(address)
print(value)
time.sleep(0.1)
We rely heavily on electronic gadgets in today's high-tech society. The digital signal is the driving force behind these digital devices. While most numbers are represented digitally, few still use analog notation. Thus, an ADC is employed to transform analog impulses into digital ones. ADC can be used in an infinite variety of contexts. Here are only a few examples of their use:
The digitized voice signal is used by cell phones. The voice is first transformed to digital form using an ADC before being sent to the cell phone's transmitter.
Digital photos and movies shot with a camera can be viewed on any computer or mobile device thanks to an analog-to-digital converter.
X-rays and MRIs are just two examples of medical imaging techniques that use ADC to go from Analog to digital before further processing. Then, they're adjusted so that everyone can follow along.
ADC converters can also transfer music from a cassette tape to a digital format, such as a CD or a USB flash drive.
The Analog-to-Digital Converter (ADC) in a digital oscilloscope converts analog signals to digital ones that can then be displayed and used for other reasons.
The air conditioner's built-in temperature sensors allow for consistent comfort levels. The onboard controller reads the temperature and makes adjustments based on the data it receives from the ADC.
Nowadays, practically everything has a digital counterpart, so every gadget must also include an ADC. For the simple reason that its operations require a digital domain accessible only via an analog-to-digital converter (ADC).
This piece taught us how to connect a Raspberry Pi 4 to a PCF8591 Analogue - to - digital decoder module. We have observed the output being shown as integers on our Terminal. We have also researched how the ADC generates its output signals. Here we will use OpenCV and a Raspberry Pi 4 to create a social distance detector.