Re: (Fwd) Re: 8032 crt vs. 3032 crt

It turns out that there is a routine in the graphic ROM that checks for 
presence of the VIDEO ON signal on PB5 of the VIA that is not in the 
business version; the problem was a broken trace from the PIA to the VIA.

m

----- Original Message ----- 
From: "William Levak" <wlevak@SDF.ORG>
To: <cbm-hackers@musoftware.de>
Cc: <stravaccato68@yahoo.it>
Sent: Sunday, June 23, 2013 7:43 PM
Subject: Re: (Fwd) Re: 8032 crt vs. 3032 crt


>
>
> It would appear from what you said, that it is the ROM itself that is the 
> problem.  You do not say exactly which version of the board and which 
> version of ROM it is.  Addressing is slightly different on some versions.
> Also access time of the ROM may be different.
>
>
> On Sun, 23 Jun 2013, Ruud@Baltissen.org wrote:
>
>> Hallo Giovi,
>>
>>
>> To be honest, I have no idea. So I forward your question to the
>> famous CBM-hackers again.
>>
>>
>> ------- Forwarded message follows -------
>> From: "Giovi" <stravaccato68@yahoo.it>
>> To: <Ruud@Baltissen.org>
>> Subject: Re: (Fwd) Re: 8032 crt vs. 3032 crt
>> Date sent: Sat, 22 Jun 2013 14:54:58 -0300
>>
>>
>> Hi Ruud,
>>
>> I have a new question for you!
>>
>> With some good and expert friends at
>> http://www.vintage-computer.com I took
>> the decision to fix the original 3032 board.
>>
>> After fixing some minor problems we arrived at a dead point.
>>
>> The computer works (boot and answer to keyboard command) only with
>> the edit
>> ROM for business keyboard. It doesn't work (it hangs with a black
>> screen
>> while booting) with the edit ROM for graphic keyboard.
>>
>> We tried with basic 2 and basic 4, of course with correct set of
>> Rom/Eprom.
>> Same result: ok with business keyboard rom, no way with graphic
>> keyboard
>> rom.
>>
>> We checked it with a petester.bin ROM and all seems ok at least
>> with this
>> simple diagnostic.
>>
>> It *seems* that some instructions in the edit ROM (at $E000) for
>> the graphic
>> keyboard make it to hang.
>>
>> Have you some experience/ideas about this?
>>
>> I also don't understand if is there any difference (jumpers,
>> components...)
>> between graphic keyboard assy and business keyboard assy...
>>
>> cheers,
>> Giovi
>>
>>
>> ------- End of forwarded message -------
>>
>>
>> --
>>
>> Kind regards / Met vriendelijke groet, Ruud Baltissen
>> www.Baltissen.org
>>
>>
>>
>>
>>
>>
>>
>>       Message was sent through the cbm-hackers mailing list
>>
>
> wlevak@sdf.lonestar.org
> SDF Public Access UNIX System - http://sdf.lonestar.org
>
>       Message was sent through the cbm-hackers mailing list 


       Message was sent through the cbm-hackers mailing list