My RAMBo board + CNC was working perfectly yesterday. Tried to it on this morning and LED is not flashing. Have tested the fuses and none seem to be blown. I have unplugged all steppers, endstops, some other servos I had connected, and a 5V fan. The only remaining connection is the external supply.
When I try to flash the firmware over USB, I see a slow blinking green LED and receive a timeout error:
avrdude: stk500v2_ReceiveMessage(): timeout
Any help would be much appreciated.