Atmega88pa using PB7 and PB6 I/O

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I have an Atmega88pa, it's signature is different than an Atmega88 but I have overcome that.

I need to have the ports PB7 and PB6 to act as I/O not as a clock. Several years ago I remember having a similar problem with a mega324. The fix, I believe, was to modify the L FUSE and H FUSE bits. I have tried to find how to do this using the datasheet to no success. Where can I find the info on what to program the fuse bits to or whatever it takes to use PB7 and PB6 for I/O?

Thanks,
Mike

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Just program the CKSEL fuses to use an internal RC oscillator as AVR clock (it's the default value, so just leave CKSEL intact).

Warning: Grumpy Old Chuff. Reading this post may severely damage your mental health.

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If you are already fused for int-RC could it be that you are using an STK500? I think most 48/88/168 users have been "bitten" by the fact that the PB6/7 IO don't appear on the PORTB header but on the X1/X2 pins on the PORTE header (for the very reason that they double up as clock pins).

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Clawson, using PORTE XT1 and XT2 fix the problem,thanks. Thanks to MBedder also.

I spent a lot of time trying to figure that one out.

I still have a question, where do I find info on how to program L and H Fuses and the rest of the fuses? Don't need it right now but I think that info is nice to know or at least where to find it, which has alluded me thus far.

Thanks, thanks very much,
Mike

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Quote:

I still have a question, where do I find info on how to program L and H Fuses and the rest of the fuses? Don't need it right now but I think that info is nice to know or at least where to find it, which has alluded me thus far.

It's all explained in the datasheet but don't touch anything without first reading my article in tutorial forum called "How to recover from a locked out AVR" which will give you a better idea of what you are about to screw up!

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If you want to know what values to set the fuses to, you can go here. http://www.engbedded.com/fusecalc