PID and Processing

Hey guys, i am new to arduino programing and i've been having some trouble interfacing my arduino code with Processing.
Basically, my code functions with a PID Controller and a solid state relay for temperature control. I wanted to use Processing so that i could input some variables using a nice window and some graphics, instead of editing the code directly.
What's happening is that as soon as the loop for the PID code starts, my relay stops working. I suspect it's because the baud rate for the PID controller (it's set to 9600) is not compatible with the Processing code (set to 115200).
I don't know what to do! Any tips will help.

I suspect it's because the baud rate for the PID controller (it's set to 9600) is not compatible with the Processing code (set to 115200).

Are you using the Serial port to talk to Processing or to talk to the PID controller (whatever that is)? Clearly, both is the wrong answer. Just for the record, so is yes.

I don't know what to do! Any tips will help.

My crystal ball says that the problem is on line 27 of string.h. But then it's never been known to be worth a rats ass.

PaulS:

I suspect it’s because the baud rate for the PID controller (it’s set to 9600) is not compatible with the Processing code (set to 115200).

Are you using the Serial port to talk to Processing or to talk to the PID controller (whatever that is)? Clearly, both is the wrong answer. Just for the record, so is yes.

The Serial port is talking to Processing directly, but the baud rate is set in the arduino code. When i set it to 9600, the realy works, but Processing stops working and when i set it to 115200, the Processing works but the relay doesn’t.

Did you see the part about my crystal ball being a piece of crap? That was a hint that you need to provide a lot more details, like your code for the Arduino and Processing, and explain what is connected to the Arduino, and how.