Re: Commodore 8296 ROM images

From: Greg King (
Date: 2002-09-04 10:46:42

-----Original Message-----
From: William Levak
Date: Wednesday, August 21, 2002 06:06 PM
> I have compared the the two 8 K (324878-01 and 324878-02) 8296 ROMs on
> funet with the 16 K (324746-01) ROM.  There were very few matches (less
> than 1000 out of 16 K).  On examining the contents of the two 8 K ROMs, I
> could not see any of the text that should be there.  Also, the fill-bytes
> at the end of the ROMs are $BA instead of the usual $AA.
> I, therefore, alterred the file to set bit 4 low wherever it was high.  This
> makes the fill-byte $AA as it should be.  It also makes the text messages
> readable, although still partially garbled.  I got about 2000 matches
> between the two versions this way.
> The rest of the two 8 K ROMs appear to be randomly garbled.

1. Bit 4 in both 8k ROMs is "stuck."
2. And, bit 5 in the first one is "stuck."
3. The daughter-board which holds those ROMs has an unusual memory-map:
   the first ROM sits in the middle of the second one!

They match the 16k ROM after I compensate for those three conditions.

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