Last week the heat bed of my Reprappro Huxley shorted the power wires, which caused the power adapter to shut off immediately. After screwing down the wires again, I plugged everything back in and got an "unrecognized USB device descriptor" message from Windows. The hotend fan turns on, and the cooling fans twitch, so it appears something is working. I switched the Melzi board to USB power, and tried re-uploading the firmware, which worked. I switched back to external power, but still got the same results. I checked the voltage regulator, and it's sending 4.93v to the ATMEGA1284P like it's supposed to.
I switched the board back to USB and plugged it in, and Windows was able to recognize the device. I can even connect to it in Pronterface, get a response from M503, and the thermistors are returning the correct values.
I can't figure out what's going on here. I set the power jumper to USB, it's recognized. Switch it so that the 19v adapter is sending 5v through the voltage regulator, it's not. I've looked at the board schematics. 5v is being directed through the jumper either way.
Edited 1 time(s). Last edit at 06/22/2019 04:27AM by HyraxAttax.