My 3 year old GQ-4X has suddenly stopped working. When plugged in, it displays Unknown USB device.This happened after writing to some dodgy SST 27SF512 chips. The reason I think they were not genuine was because I was not able to erase them after writing to them. I have re-installed Windows twice without any improvement. I have also tried using another computer. I have also tried supplying 9V DC.
I was able to revive it once by repeated plugging in and out. It worked after 20 tries of that. However since then it's not worked. I have also tried another USB cable without success.
Shipping it back to Mcumall is not possible since that would cost more than another programmer.
Mcumall support: Is there any kind of guide you can give me to check and repair whatever has failed in the programmer? If there are capacitors or resistors that might have caused this, I would be able to fix it, if it's something more complex, I'd have to write it off and buy another one.
Just before I trashed the programmer, I found that the 2nd cable I had tried was faulty as well. I did this by trying it on another device (printer). So I bought yet another cable and it's now working perfectly.
Attn Mcumall support: GQ-4X: Unknown USB Device
Posted - 02/02/2012 : 22:57:46
