arduino does not receive serial data

Question

I want to sent a string from processing to arduino. but the arduino does not receive any data from serial... see below for the processing code:

import processing.serial.*;
Serial myPort;

void setup(){
    String portName = Serial.list()[2];
    myPort = new Serial(this, portName, 9600);
}

void draw(){

    myPort.write(parseRed + " | " + parseGreen + " | " + parseBlue);

}

see here my arduino code:

String serialData;

String serialDataRed;
String serialDataGreen;
String serialDataBlue;

void setup(){
   Serial.begin(9600);

}

void loop(){

   if (Serial.available()) {
      serialData = Serial.readString();

      serialDataRed = serialData.substring(0, 5);
      serialDataGreen = serialData.substring(9, 16);
      serialDataBlue = serialData.substring(20, 26);
   }

}

when I run this script nothing happens arduino doesn’t see to receive any data... can someone tell me what I am doing wrong??

What is `parseRed`, `parseGreen`, and `parseBlue`? Where are they defined and what are their values? Does the Arduino `loop()` function ever get called? Does it enter that if statement? You'll have better luck if you post a [mcve] and tell us the debugging steps you've already done. — Kevin Workman, Apr 05 '16 at 21:06
parseRed, parseGreen, parseBlue are strings. they look like the following: "minRed" or "neuGreen" or "maxBlue" and so on. and yes the loop() function does get called because it is the same as the draw() function in processing. — FutureCake, Apr 05 '16 at 21:08
But how do you know it's actually being called? Have you done any debugging to guarantee that's the case? You have to narrow down the problem to a specific place where the code's actual execution differs from what you expect. We can't really help with that unless you post a [mcve] that shows the code you're actually running. — Kevin Workman, Apr 05 '16 at 21:18

score 0 · Answer 1 · answered Apr 05 '16 at 22:41

well i found my error :D kinda a stupid mistake dough...

String portName = Serial.list()[2];

should be:

String portName = Serial.list()[3];

because my arduino was connected to a different usb port then before... so the lesson is: check if you are using the right port... thank you kevin for the help dough :)

arduino does not receive serial data

1 Answers1