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Old 17th Mar 2021, 10:07 pm   #1119
ScottishColin
Octode
 
Join Date: May 2012
Location: Perth, Scotland
Posts: 1,802
Default Re: Non-working Commodore PET 3016

UG7/10 settles at 5.3V after a few seconds.

Re UG7 9 and 11 - see attached. I get a signal on UG7/9 (green) but nothing on UG9/11 (yellow).

Colin.


Quote:
Originally Posted by SiriusHardware View Post
Can you check with a meter or scope to confirm that UG7 pin 10 is held high (4-5V).

If it is can you scope UG7 pins 8 and 11 both at the same time, one above the other on your scope. Just trying to follow the system RAM read signal backwards for a while.

Edit, sorry, typo: UG7 Pins 9 and 11 both at the same time. Hope I caught you in time.
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