Re: identifying an unknown eprom content

From: didier_at_aida.org
Date: Thu, 27 Aug 2020 13:38:32 +0200
Message-ID: <5c79870e-276b-5177-58ba-35516c115dd5_at_aida.org>
the vectors are present but all strangely set at $E000
apparently there are 2 peripherals
one at $4000  uses $4000 to $4003  perhaps a PIA
another one at $8000  seems to be program a way similar to a crtc
a value written at $8000 (perhaos the index in the chip) and another in 
$8001


On 27/08/2020 13:19, groepaz_at_gmx.net wrote:
> Am Donnerstag, 27. August 2020, 13:14:05 CEST schrieb didier_at_aida.org:
>> I know very little about this eprom
>> it was given to be by commodore maintenance about 30 years ago
>> according to the label it was supposed to work on a network board
>> installed in a 8032 motherboard
>> obviously it's not the case
>> I'm thinking to a c64 cartridge in ultimax mode (booting in $E000)
>> I'm trying to get a better disassembly and some clue to go further
> an ultimax cart starts via the hardware reset vector at $fffc - so if you find
> a vector there that points to code that looks like startup code, perhaps thats
> it. you should also find a valid NMI and IRQ vector then at $fffa and $fffe
> respectively
>
> --
>
> http://hitmen.eu                 http://ar.pokefinder.org
> http://vice-emu.sourceforge.net  http://magicdisk.untergrund.net
>
> I recognize that a class of criminals and juvenile delinquents has taken to
> calling themselves 'hackers', but I consider them irrelevant to the true
> meaning of the word; just as the Mafia calls themselves 'businessmen' but
> nobody pays that fact any attention.
> <Robert Bickford>
>
>
>
>
>
Received on 2020-08-27 14:03:26

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