9700 almost working

[Tim Ressel]

Terry,

Check this line for shorts. If the uP is socketed, simply list the pin and scope
it: if the uP pin is moving, you have a short somewhere. If not, it may be that
the uP is blown.

Tim Ressel--Hardware DQ
Hewlett-Packard
Verifone Division
916-630-2541  
tim_r1 at verifone.com 



> ----------
> From: 	KA4HJH[SMTP:ka4hjh at gte.net]
> Sent: 	Tuesday, July 27, 1999 10:23 PM
> To: 	synth-diy at mailhost.bpa.nl
> Subject: 	9700 almost working
> 
> Got my PAiA 9700 almost finished. Everything seems to be working except:
> Pin 16 on the mcu (P36/NOT WR) is always high. It should be strobing.
> Needless to say nothing is being written to the DAC. I don't have any 8031
> docs so I don't know exactly what is going on here. Is one line on my
> processor zapped?
> 
> BTW, with nothing coming out of the DAC the buffer amps all drop to the
> negative rail in a few seconds. Didn't someone have a problem with this
> just recently?
> 
> Thank god I have a 'scope.
> 
> Terry Bowman, KA4HJH
> "The Mac Doctor"
>