CircuitPython-DMX

Using Circuitpython to Move Motors, Change Colors and Make sound with DMX Interface

I am studying ways to create stage devices with movement, light and sound that can be controlled from the operating booth in a theatrical show.

This first prototype was developed using the CytronTech Maker Pi RP2040 board, with CircuitPython and the CircuitPython DMX Receiver library https://github.com/mydana/CircuitPython_DMX_Receiver

The system receives the DMX signal, breaks down each of the channels and assigns the values ​​to specific devices on the board, activating Neopixel LEDs with specific colors, moving servomotors and motors. It would also be possible to assign sounds and have the board's buzzer emit them.

import board, neopixel
from simpleio import map_range
import pwmio
from adafruit_motor import servo, motor

# Copy files from https://github.com/mydana/CircuitPython_DMX_Receiver onto lib folder
from dmx_receiver import DmxReceiver 

DMX_PIN = board.GP1 # Módulo RS 485
PIXEL_PIN = board.GP18 # neopixel on board, dois LEDS RGB

# Read 16 sequential channels from DMX starting at Slot 0
dmx_receiver = DmxReceiver(pin=DMX_PIN, slot=0) 
       # pin: The pin to retrieve data from.
       # dmx_basis: If True start slot numbers at 1 not 0. - Use true, to follow DMX Channel standards
       # slot: The first DMX slot of 16 to listen for.

# Neopixel Setup
pixels = neopixel.NeoPixel(PIXEL_PIN, 2)

servo_pwm1 = pwmio.PWMOut(board.GP12, duty_cycle=2 ** 15, frequency=50)
servo_pwm2 = pwmio.PWMOut(board.GP13, duty_cycle=2 ** 15, frequency=50)
servo_pwm3 = pwmio.PWMOut(board.GP14, duty_cycle=2 ** 15, frequency=50)
servo_pwm4 = pwmio.PWMOut(board.GP15, duty_cycle=2 ** 15, frequency=50)

motor1_pwm_a = pwmio.PWMOut(board.GP9, frequency=50)
motor1_pwm_b = pwmio.PWMOut(board.GP8, frequency=50)
motor1 = motor.DCMotor(motor1_pwm_a, motor1_pwm_b)

motor2_pwm_a = pwmio.PWMOut(board.GP10, frequency=50)
motor2_pwm_b = pwmio.PWMOut(board.GP11, frequency=50)
motor2 = motor.DCMotor(motor2_pwm_a, motor2_pwm_b)

servo1 = servo.Servo(servo_pwm1)
servo2 = servo.Servo(servo_pwm2)
servo3 = servo.Servo(servo_pwm3)
servo4 = servo.Servo(servo_pwm4)


for data in dmx_receiver:
    if data is not None:
        # Convert Bytes to a Integer List - Debug only
        dmx_list = list(data)
        print(dmx_list)
        
        # CHANNEL 1, 2, 3 e 4 - RGB and Brightness
        color_red = dmx_list[0] # Channel 1
        color_green = dmx_list[1] # Channel 2
        color_blue = dmx_list[2] # Channel 3
        pixels.brightness = map_range (dmx_list[3], 0,255, 0.0,1.0) # Channel 4
        
        pixels[0] = (color_red, color_green, color_blue)
        pixels[1] = (color_red, color_green, color_blue)        
        pixels.show()
       
        # Channels 5 to 8, Four Servo positions
        servo1.angle = map_range (dmx_list[4], 0,255, 0,180) # Channel 5
        servo2.angle = map_range (dmx_list[5], 0,255, 0,180) # Channel 6
        servo3.angle = map_range (dmx_list[6], 0,255, 0,180) # Channel 7
        servo4.angle = map_range (dmx_list[7], 0,255, 0,180) # Channel 8
        
        # Channels 9 and 10 - Motor 1 Speed and Direction
        motor1_speed = map_range(dmx_list[8], 0,255,0, 1.0) # Channel 9
        motor1_direction = dmx_list[9] # Channel 10
        
        if motor1_speed == 0:
            motor1.throttle = None # Shutdown Motor
        else:
            if motor1_direction in range (0,127):
                motor1.throttle = motor1_speed
            else:
                motor1.throttle = motor1_speed * -1.0

        # Channels 11 and 12 - Motor 2 Speed and Direction  
        motor2_speed =  map_range(dmx_list[10], 0,255,0, 1.0) # Channel 11
        motor2_direction = dmx_list[11] # Channel 12

        if motor2_speed == 0:
            motor2.throttle = None
        else:
            if motor2_direction in range (0,127):
                motor2.throttle = motor2_speed
            else:
                motor2.throttle = motor2_speed * -1.0