Hangs on entering fuse values

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af7ux
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Joined: Wed Jul 13, 2022 9:24 am

Hangs on entering fuse values

Post by af7ux »

Hello - I am trying to reset the fuses on what I believe is a clone 328p. It's in a QFN28 package, and I have an adapter & jumper cables to connect the pins to the DIP socket. Per the datasheet, I had to move the pins as the number to function assignment are not the same (they're offset by 4 pins).

When programming, I get as far as entering the desired lfuse value, and then it just hangs.

Sketch Version 212, arduino 1.8.19.

Code: Select all

Select mode:
1: ATmega (28-pin)
2: ATtiny2313
3: ATtiny (8-pin) / HVSP
Selected mode: ATMEGA
Insert target AVR and press button.

Existing fuse values:
LFUSE: 0
HFUSE: 0
EFUSE: 0

Enter desired LFUSE hex value (ie. 0x62): 
Thanks,
Derek
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mightyohm
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Location: Seattle, WA
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Re: Hangs on entering fuse values

Post by mightyohm »

Not totally sure what's happening here, most likely it is hanging because it can't communicate with the target. Do you have another part (like a genuine 328p) you can try?

Can you tell me more about the target? I'm not familiar with any clones of the 328p.
af7ux
Posts: 4
Joined: Wed Jul 13, 2022 9:24 am

Re: Hangs on entering fuse values

Post by af7ux »

Unfortunately, I don't know much about the clone, it came out of a device and I cannot get another right now, or at least not in that footprint.

Looking at the code, it looks like that section shouldn't be talking to the target, as it's just doing serial reads? If I add some print statements it seems like it's hanging on

Code: Select all

while (Serial.available() == 0);   // wait for a character to come in
in fuse_ask.
af7ux
Posts: 4
Joined: Wed Jul 13, 2022 9:24 am

Re: Hangs on entering fuse values

Post by af7ux »

Well, it was my soldering. The breakout is double sided and I had originally used the wrong side and forgot to clean up solder bridges, but it is connected to the pins on both sides. Fixed that and now it's working!

Thanks,
Derek
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mightyohm
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Re: Hangs on entering fuse values

Post by mightyohm »

Derek,

That's great news. Glad you got it working!
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