I have a Spark that I think I might have damaged soldering into a carrier PCB. The core seems to be running REALLY slow. When you first power it up, it flashes white for a number of seconds. I think the white flash (and all the LED flashes) are actually the firmware modulating the LED.
I can get it into Yellow Flash DFU mode, but the device is not recognised. I have tried a Factory Reset, but that did not help either. And it is not appearing as a serial port on the USB either.
I am just wondering what I should do, and what the issue is? Have I somehow fried the firmware - where uploading it again with JTAG might help