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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: DGB on November 26, 2004, 05:46:30 PM

Title: 3.1 ROM CHIPS
Post by: DGB on November 26, 2004, 05:46:30 PM
Does anyone know if the 3.1 ROM chip used in the CD32 is in fact the same chip as used in the A2000.  They look as if they are the same.  Thanks.

Dave
Title: Re: 3.1 ROM CHIPS
Post by: Jeff on November 26, 2004, 06:14:17 PM
They are not the same.  The CD32 is a 42 pin 1 meg rom (I Think) and the A2000 is a 40 pin 512k rom.

I often wondered if the CD32 Rom would fit in the 42 pin socket found on some A1200 motherboards and if that would work.  If not, then what was the reason for including a larger socket on the 1200? I'm sure this has already been discussed somewhere.

Jeff
Title: Re: 3.1 ROM CHIPS
Post by: nex4060 on November 26, 2004, 06:48:04 PM
hmm if you could make the CD32 3.1 ROMs work in an A1200 would you then get CD-ROM access direcly from a cold boot?
Title: Re: 3.1 ROM CHIPS
Post by: pjhutch on November 26, 2004, 06:51:46 PM
Unlikely as the CDROM in the CD32 is propietary and would not work on other systems...
Title: Re: 3.1 ROM CHIPS
Post by: Piru on November 26, 2004, 06:51:48 PM
Quote
hmm if you could make the CD32 3.1 ROMs work in an A1200 would you then get CD-ROM access direcly from a cold boot?

No.
Title: Re: 3.1 ROM CHIPS
Post by: DGB on November 26, 2004, 07:09:56 PM
That answers my question.  Thanks.

Dave
Title: Re: 3.1 ROM CHIPS
Post by: TjLaZer on November 26, 2004, 08:39:23 PM
The CD32 is a 32-bit computer, AGA, like the A1200, A4000, thus two chips, the A2000/A500 is 16-bit, one chip.
Title: Re: 3.1 ROM CHIPS
Post by: adolescent on November 26, 2004, 10:09:11 PM
Quote

TjLaZer wrote:
The CD32 is a 32-bit computer, AGA, like the A1200, A4000, thus two chips, the A2000/A500 is 16-bit, one chip.


No, CD32 is a single chip.
Title: Re: 3.1 ROM CHIPS
Post by: TjLaZer on November 26, 2004, 10:11:40 PM
Really?  That is weird, I thought it was based on the A1200.  Interesting.
Title: Re: 3.1 ROM CHIPS
Post by: Doobrey on November 26, 2004, 11:57:35 PM
Yup, it is a 32 bit machine loosly based on the A1200.. but some bright spark at Commodore decided to use a single 16 bit rom (maybe the usual cost cutting?) and setup the hardware to only do 16bit reads at the rom addresses.
 The PCB has the holes for a second socket, and the schematics  show that you just need to install a 74F125 at XU1 and change the jumper XJ1 to get it working in 32bit mode....erm and split the rom into 2 chips!