8375 Agnus Questions

[jasonsbeer]

I am looking at the dizzying array of 8375 part numbers for the next revision of the Amiga 2000 EATX board. I am referencing this table.

Also found this...Agnus History.

Can some of you who are knowledgeable about this please verify the table below? From what I can find, these are all pin compatible EXCEPT for the noted differences. I want to make sure I am not missing some bit of information.

Part Number..PAL/NTSC..Comment
390554-01.....PAL.............8375R0 Original Release
390554-02.....NTSC..........8375R0 Original Release
318069-10.....PAL.............Differs from 390551-01, pin 40 is Vbb instead of 14MHz
318069-11.....NTSC..........Differs from 390551-02, pin 40 is Vbb instead of 14MHz
318069-12.....PAL.............New revision of 390544-01
318069-13.....NTSC..........New revision of 390544-02

Edited part numbers. I replaced my original table. So confusing...

[A4000Bear]

390544-01 and -02 are not pin compatible with 318069-10 or-11. Also not pin compatible with any other Agnus versions. These were used only in the A600, A500+, and some 3rd party 'megachip' expansions.

The differences are more than just the VBB pin. Careful comparison of an A3000 schematic and a Rev 8 A500+ schematic will reveal the differences. These are mostly in the DRA lines (pins 43-51 & 56 for the A3000, and pins 42-50 & 55 for the A500+ using the 390544-01/02)

[alexh]

There is a thread on here detailing the exact differences. Use search and I'm sure you can find it. It is a discussion between me (who compiled the list of all Agnus types we all use today) and Zetr0

[jasonsbeer]

Originally Posted by alexh

There is a thread on here detailing the exact differences. Use search and I'm sure you can find it. It is a discussion between me (who compiled the list of all Agnus types we all use today) and Zetr0

I'll check it out.