Raspberry Pi 4 Project 01
From ikev.in/w
LED Bar Graph Pulsating Project
This project involves creating a 10-LED bar graph that pulsates light using a Raspberry Pi 4 and Python code. The LED bar graph will have 10 bars, each controlled by a GPIO pin on the Raspberry Pi.
Required Materials
To complete this project, you will need the following materials:
- Raspberry Pi 4
- Breadboard
- 10 LEDs
- 10 220-ohm resistors
- Jumper wires
Circuit Diagram
The circuit diagram for this project is shown below:
In this diagram, each LED is connected to a GPIO pin on the Raspberry Pi through a 220-ohm resistor. The GPIO pins used for each LED are as follows:
- LED 1: GPIO 21
- LED 2: GPIO 20
- LED 3: GPIO 16
- LED 4: GPIO 12
- LED 5: GPIO 7
- LED 6: GPIO 8
- LED 7: GPIO 25
- LED 8: GPIO 24
- LED 9: GPIO 23
- LED 10: GPIO 18
Python Code
The Python code for this project is shown below:
# Wait a short amount of time time.sleep(0.05) # Decrease the duty cycle from 100 to 0 in steps of 5 for dc in range(100, -5, -5): # Set the duty cycle for each LED for i in range(len(led_pins)): GPIO.output(led_pins[i], dc > (i*10)) # ^^^ If the duty cycle is greater than the threshold for this LED, turn it on. # Wait a short amount of time time.sleep(0.05)