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Old 12th Mar 2021, 1:20 pm   #959
ScottishColin
Octode
 
Join Date: May 2012
Location: Perth, Scotland
Posts: 1,804
Default Re: Non-working Commodore PET 3016

Done - apologies. It is possible I'll get the hang of this one day.

Do any of my previous ones need repeating?

Colin.


Quote:
Originally Posted by Mark1960 View Post
Colin, when looking for activity on R/W and related signals switch your scope to trigger on falling edge.

After the initial burst of writes there will only be brief intermittent negative pulses on the R/W signals and your scope trigger on positive edge might not display the negative pulse.

Edit: Also change the trigger level back to 1.4v, your last set of traces look like they were triggering on negative overshoot, and there might not be enough overshoot on all the signals.
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