AVR-Chat

Check your scope ground.  I use all kinds of different embedded 
processors, PICs included, and I've used the F877 with 'HC595's too with 
great success.  What is your code doing and are you constants switching 
the DDR from inputs/outputs?  How is your power rail?  If it is bouncing 
around so too will logic levels.  Basically, you haven't given enough 
information for any kind of a suggestion to be made.

DLC

OWEN-A wrote:
> I know this is perhaps a bit off topic but I have several boards with
> PIC16F877 processors driving an HC595 shift register and the output pins
> from the pic driving the HC595 are virtually all glitches.
> 
> It is hard to pick up a high or low as such on the logic analyser other
> outputs seem ok, has anyone any idea what may be causing this. 
> 
> And yes I do not like pic's I normally use AVR'S.
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> Yahoo! Groups Links
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Dennis Clark    TTT Enterprises
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