Re: basic1-patch from vice in a real PET

From: André Fachat <afachat_at_gmx.de>
Date: Wed, 07 Feb 2018 21:47:35 +0100
Message-ID: <16172060e58.27b9.b4d1f2b66006003a6acd9b1a7b71c3b1@gmx.de>
Am 7. Februar 2018 16:53:09 schrieb André Fachat <afachat@gmx.de>:

> It could also be because IIRC the EOI line has moved or is reused in the
> first PET and Vice could have a buf in that area.

Hm, CA2 of the keyboard PIA is used as EOIout. However in the first PET 
activating EOI also blanks the screen. Now the question whether something 
during load blanks the screen thus asserts EOI and breaks IEEE488 with 
this. As any print out blanks the screen maybe the "LOADING" already does 
this. On the other hand the drive only checks during an actual transfer 
IIRC but during this time nothing is printed....

What are the actual symptoms? How does it compare to VICE?

Do you have a scope to look at the symptoms?

Does a BASIC program work that actually loads a file with BASIC OPEN and GET# ?

Regards
André



> IiRC that had to do with the vertical retrace to avoid the snow on the
> screen. Maybe if you check the schematics ...
>
> That it works with commands may be pure Timing luck.
>
> André
>
> Am 7. Februar 2018 15:19:22 schrieb vossi <vossi@ceffy.de>:
>
>> Hallo Andre, I know this with the load addresses.
>> But why your patch works great in vice xpet and not in my real 2001 with
>> patched eprom installed???
>>
>> greets aus Hamburg
>> Christian
>>
>>
>>
>> --
>> Sent from: http://cbm-hackers.2304266.n4.nabble.com/
>>
>>        Message was sent through the cbm-hackers mailing list
>
>
>
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Received on 2018-02-07 21:00:03

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