PIDassist can be operated in 3 main modes:

All in PC. The controller is simulated in the PC as well as the target (controlled) process. The SPLat board serves only as a dongle to unlock certain features.

SPLat + PC. The PID control calculations are performed in the SPLat board, by a program we supply, with the process simulated in the PC. Communication between the two is via SPLatLink. This is very slow, because the serial data communications take so much time. I used this early in the development of PIDassist and will eventually remove it.

All in SPLat. In this mode the SPLat is allowed to control the real process. The PC and PIDassist can be used to fine-tune the PID control parameters within the SPLat board. To do this you have to be using a SPLat program we supply that knows how to use PC-supplied parameters. In this mode two bytes of data are extracted from the SPLat board and displayed/logged. This opens the door to logging the performance of your PID system. It also to gives you a way of characterizing your process at an earlier stage of the proceedings.