Hi @HITman, I think you need to post your Arduino code as well. Can we confirm something re serial ports? How many serial devices are there? and Serial.list[0] finds the right one? Look in device manager and try these 2 lines instead of your 1 line.
print("Arduino found on Port:");
println(Serial.list());
The code you have prints gobledegoop and assumes the one Ard is the only serial device. I prefer to name the device I want: (and keep to 9600 everywhere until you need more speed.)
new Serial(this , "COM1", 9600);
What Arduino are you using? It’s good to have other output from the Ard to help you see what’s going on. Do you have ttl-to-usb adaptor? lcd/oled screen?
Keep to a strict sequence. Processing sketch stopped. Connect Arduino (if CH340 use the same usb socket each time.) Start and stop Processing sketch as many times as you like.