Go Down

Topic: Messed up some fuses (Read 1 time) previous topic - next topic

omni96

Hi,

I used some ISP programmer, and re-programmed the fuses on some Arduino UNO's (on the usb 8u2 chip)
One doesn't enable uploading sketches, and others just don't communicate over serial.
For some reason, ISP programming is no longer working also.

I read that one can use a crystal to "revive" the mcu, so I bought some crystals, but I'm not sure what should I do now.

So where do I plug in the fuses?

fungus


Hi,

I used some ISP programmer, and re-programmed the fuses on some Arduino UNO's (on the usb 8u2 chip)


Bad move.


I read that one can use a crystal to "revive" the mcu, so I bought some crystals, but I'm not sure what should I do now.

So where do I plug in the fuses?


According to the schematic the USB chip has its own crystal:

http://arduino.cc/en/uploads/Main/Arduino_Uno_Rev3-schematic.pdf

You can't add more...so crystals aren't going to help. You must have done something else.

No, I don't answer questions sent in private messages (but I do accept thank-you notes...)

omni96

I it possible I will have to replace the 16 mhz crystal with a 8 mhz one?

Tom Carpenter

If ISP is not working then it means you have most likely disabled either the reset pin, or serial programming. In which case the only way to recover them is to use a high voltage programmer to burn the correct fuse settings.

Do you know what fuse values you actually set?
~Tom~

omni96

These: Low-41 High-D9 Ext-FF

Go Up