Read Serial Value (From Arduino)

Processing.py
1

Hey,

so all I’m trying to do is use processing to read a value from the Serial port of an arduino. I have already connected I just don’t know the correct python method to read the value.

Current code:

def setup():
    global arduino
    size(10,10)
    
    println(Arduino.list())
    
    arduino = Arduino(this, Arduino.list()[1], 9600)
    
def draw():
    #val = arduino.analogRead(0)
    
    for i in range(10):
        val = arduino.readString(i) #<----------------- Here 'readString' doesn't work, what should this be?
        print("{} ___ {}".format(frameCount,val))
    delay(10000)

Many thanks

2

This is my lousy attempt to convert an old Java Mode sketch from the link below to Python Mode: :snake:

"""
 * Efficient Serial Reading (v1.01)
 * GoToLoop (2018-Nov-22)
 *
 * Discourse.Processing.org/t/read-serial-value-from-arduino/5829/2
 *
 * Forum.Processing.org/two/discussion/16618/
 * processing-with-arduino-void-serialevent#Item_5
"""

add_library('serial')

PORT_INDEX, BAUDS = 0, 9600
myString = ''

def setup():
    noLoop()
    ports = Serial.list()
    Serial(this, ports[PORT_INDEX], BAUDS).bufferUntil(ENTER)


def draw(): print myString


def serialEvent(s):
    global myString
    myString = s.readString().trim()
    redraw()

Since I don’t have any of such hardware, I can’t tell whether it’ll work or not. :no_mouth:

You should ask in the repo below if it doesn’t work for you: :face_with_head_bandage:

3

It does not work.

This will work with Processing 3.5.4 Python mode:

# Python Serial Reading
# v1.0.0
# GLV 2022-06-11

add_library("serial")
myPort = Serial(this, "COM2", 9600)
inString = ""

def setup():
    size(400, 100)

    # This does not work:
    #myPort.bufferUntil(ENTER)
    
    # This works:
    myPort.bufferUntil(0x0A)
    
    textSize(24);
    textAlign(LEFT, CENTER);
    fill(0);
    noLoop()
    
def draw():
    background(255); # I needed something here
    text (inString, 50, height/2);
    
def serialEvent(Serial):
    global inString
    
    # This does not work:
    # inString = myPort.readString().trim() 
    
    # This works:
    inString = myPort.readString()
    inString = trim(inString)
    
    println(inString)
    
    arr = inString.split(",")
    for i in arr:
        print(i)
    
    redraw()

Above code does NOT work with Processing 4.0.b8

You can use a virtual serial port if you do not have hardware.
There is one available here:
https://www.hhdsoftware.com/
See bottom for free version.

Use any serial software or code of your choice to send serial data.
I used the Serial Monitor that comes with Arduino software (hardware not required) to send data.

image
image630×618 26.1 KB

This is the link to the free virtual serial port software that I tested:

Disclaimer: Use at your own risk!
This is just one of many options out there.

:)

1 Like