Drawing in Python using Arduino data via serial

Categories Open-source, Programming, Visuals

Following on from my previous post where I established serial communication between an Arduino and a Raspberry Pi, I needed to find out if I could store the data being sent from the Arduino in a variable on the Raspberry Pi and use it to alter some functions in a Python script.

I wrote up a piece of code that tries to read the data from the serial and use it to change the colour of a circle drawn in the center of a 640 x 480 pixel screen:

# Title: Arduino2RPiSerial
 #
 # Goal: to draw a circle based on colour values sent from the arduino
 #

import pygame
 import sys
 import serial

pygame.init()

#create a screen
 screen = pygame.display.set_mode((640,480))

#create colour
 redValue = 255
 fgColour = (redValue,0,0)
 bgColour = (0,0,255)

screen.fill(bgColour)

#serial(device,baud)
 ser = serial.Serial('/dev/ttyACM0',9600)

# LOOP
 while 1 :

#Update from serial
 redValue = ser.readline()
 #update colour value
 fgColour = (redValue,0,0)
 pygame.draw.circle(screen, fgColour, (320,240), 200, 0)
 pygame.display.update()
 pygame.time.delay(5)

# check for quit events
 for event in pygame.event.get():
 if event.type == pygame.QUIT:
 pygame.quit(); sys.exit();