Setup a data packet with the values you want to log, and send them back to the PC over the serial line. Use the PC application to retrieve the data and store it however you need. You will more than likely have to develop a protocol so you can send commands to move the motor or commands to gather the data from the PIC. Sounds like you have half of the work already done. I'm assuming you wrote the PC interface with the PIC. Bruce... no need to pay for advertising... yet another free plug! HERE'S an example of what you could do. Get to know Bruce's site (if you haven't already), there's tons of examples to learn from there. Hope I've helped... Good luck!