Now that I have data to send from the computer to the arduino, I’d like to verify that it has gotten to the arduino. My original assumption was that I could echo back the data and read it on the arduino serial monitor. Unfortunately, it appears that when a program in Processing is running the serial port, the arduino serial monitor capability doesn’t work.

My short-term solution is to have the arduino’s built-in LED at pin 13 serve as kind of a low-res serial monitor. When a byte value of 67 is received over the serial port, the arduino sketch writes pin 13 high. Why 67? It’s the last byte value in the path file that I wrote and am using for testing purposes.

Anyhow, when I transferred the data from the computer to the arduino, pin 13 did indeed come on:

This is an improvement over the null pointer errors that crashed GIRC when I initially tried to transfer data, but still I want to verify that all the bytes are getting over to the arduino. So that’s where I’ll be heading next.