I’ve put together a 16-servo. The initial power-on test went just fine. I had to fumble around with my software quite a bit before I figured out how to send commands. In the process, I sent a lot of random stuff to the board. during one of my sessions, the red LED came on. Anyway, I unhooked the board while I sorted the software. When I hooked it back up, all of the LEDs light and won’t go out. I bought two kits (one as a backup). When I replace the PIC on the board with the one from the backup kit, everything seems to work properly. When I replace the original processor, all LEDs light (and, serial commands don’t work).
Does that mean the PIC is fried? Or, is it possible that some random command I sent accidentally could have placed it into a mode that’s causing the problem? (and, thus might be recoverable
Unfortunately, the chip-swapping test you did is a good indication that the PIC is dead, and that’s not something recoverable. It sounds like the serial input pin is damaged, which could be caused by excessive voltages on the pin (e.g. by accidentally connecting RS-232 levels directly to the logic-level input). Do you know what might have happened?
I was afraid of that. Well, I probably accidentally bumped the S line with the “+” power when I was futzing around originally since I was using clips rather than a proper connector to power the board (and, I was using a 16v power supply) … that’ll teach me! I was going to order a backup PIC anyway, to have on hand … but, do you have a policy of replacing a single PIC for a reduced cost in a situation such as this, by any chance?
