Amiga 2000 Rev. 4 motherboard uses?

[snowfire]

Found the dreaded German Amiga 2000 Rev. 4 motherboard today while going through my old tech stacks. It is supposed to be in working condition. ( got it for free many years ago on top of Amiga 2000 I bought, but never tried it. ). Kickstart rom is missing but that's not a problem as I have some lying around somewhere. It also looks like it's in pretty nice condition.

Pictures:

https://drive.google.com/file/d/1-El..._gEZszLlg/view

https://drive.google.com/file/d/1BkW...rxL0Z0KfA/view

Now I'm wondering if I could make it live again..

.. so I have some questions:

1. Is it possible to connect ATX power to this? Can't seem to find any J300 jumper in this which would be requirement?

2. Would this support installing Kipper2K A508IDE Fastmem with IDE -board?

3. Would this support installing Vampire 500 V2+ ?

Plan would be to not install any Zorro-bus-cards as my understanding is that this motherboard version doesn't handle anything in the bus well.

Thanks

[NorthWay]

Rev 4 is bit generic. I had a 4.2 that was definitely not German. AFAIK 4.1 was a pre-release version.
Wasn't the German the 'A' model and the US the 'B' model?

[idrougge]

Originally Posted by NorthWay

Rev 4 is bit generic. I had a 4.2 that was definitely not German. AFAIK 4.1 was a pre-release version.
Wasn't the German the 'A' model and the US the 'B' model?

Indeed it was, and indeed all revision 4 boards aren't model A boards.

They aren't incompatible with Zorro boards as such, either. There were enough A2000A boards out there for manufacturers to make sure that their cards worked with such motherboards.

[Codetsu]

board have only 512k chip mem it have additional 512k mem board
just like A500 and trapdoor additional mem

but bad thing is additional mem locate CPU connector ?!

and there is no (buster chip) for Zorro

[zipper]

This is model A as it's having 0.5 MB 8367 Agnus.

[Jope]

The best use for this is probably for harvesting Agnuses to replace ones in dead A1000s. ;-)

Then again I haven't ever seen a dead Agnus in an A1000 so far..

[mark_k]

Originally Posted by idrougge

Indeed it was, and indeed all revision 4 boards aren't model A boards.

They aren't incompatible with Zorro boards as such, either. There were enough A2000A boards out there for manufacturers to make sure that their cards worked with such motherboards.

Definitely. Even (many) CPU-slot accelerator boards worked on the German A2000, though you had to remove the 68000 CPU first.

With regard to board revisions, it's likely that the German and later US-designed boards were considered separate products. So rev 4 existing of both board types is a coincidence rather than e.g. all US-type boards having to be a later rev. than all German ones.

[idrougge]

Indeed Commodore Westchester started numbering the B2000 at revision 4, but due to some bugs, the first B2000 to be shipped was rev 4.1.

B2000 was also known as A2000-CR, for "cost-reduced". The original Brunswick A2000 was immensely expensive to manufacture, with a huge four-layer motherboard produced in West Germany. The greatest cost reduction of the B2000 was moving to a cheaper two-layer board layout.

[Marchie]

Originally Posted by Jope

The best use for this is probably for harvesting Agnuses to replace ones in dead A1000s. ;-)

Then again I haven't ever seen a dead Agnus in an A1000 so far..

Doesn't the A1000 have Agnus in a DIP package, (not PLCC)?

Or have I just failed to pick up the obvious sarcasm...probably the latter... :P

[Jope]

Originally Posted by Marchie

Doesn't the A1000 have Agnus in a DIP package, (not PLCC)?

Or have I just failed to pick up the obvious sarcasm...probably the latter... :P

You need to look at the A2000 motherboard pics again in the first post, we're talking about an A-model. :-)

Sent from my E5823 using Tapatalk

[Marchie]

Originally Posted by Jope

You need to look at the A2000 motherboard pics again in the first post, we're talking about an A-model. :-)

Sent from my E5823 using Tapatalk

I thought Rev 4 was the B-model. My bad.

[Jope]

Originally Posted by Marchie

I thought Rev 4 was the B-model. My bad.

Yeh, confusingly the most common boards of both models are rev 4.x :-)

[snowfire]

Ok. Getting somewhere..

Just to clarify:
Rev 4 = Amiga 2000A
Rev 4.1->4.x = Amiga 2000B
In 2000A motherboards it reads Rev 4 and in 2000B motherboards it reads 4.x so it's ~pretty clear but blame Commodore for all the confusion..

About my questions.. I'm answering myself:
1. Asked AmigaKit about their Amiga2000 PSU adapter and indeed it would need J300 jumper to get the tick signal, which Rev 4 hasn't got. One could make tick-signal generator or add a cable in the motherboard to do what the J300 jumper does. So it is possible but get's a bit tricky.. I do consider Amigas electronics-hobby anyway and got to start somewhere..
2. I guess it would work but installing is quite tricky.
3. I guess would work too and would probably be most suitable for this machine if/when there is update to ignore the real custom-chips and implement them inside Vampire. This would of course make real Amiga's role pretty small. And to get keyboard I would buy some Lyra-adapter. Just feels a bit crazy to go this route as building dedicated Linux/FS-UAE machine would cost the same and be a lot more powerful.. But maybe I will do this in the end.

One more question: Would Action Replay Mk3 ( amiga 2000 model ) work with this mobo? Installing such card and using this machine as real games-machine would be another possibility..

[dalek]

1. Ian Stedman has an adapter that will give you the tick signal: http://www.ianstedman.co.uk/Amiga/de...x_adaptor.html

[snowfire]

Originally Posted by dalek

1. Ian Stedman has an adapter that will give you the tick signal: http://www.ianstedman.co.uk/Amiga/de...x_adaptor.html

Thanks! Those seem perfect. I think I'll order one or two.

[idrougge]

I don't see why the Action Replay wouldn't work.

[thebajaguy]

From all that I have read from Dave Haynie's posted tech notes, the German A2000 'Rev 4' is an A1000 with a Zorro card cage on the side. The CPU slot use (by an 86-pin accelerator) requires the removal of the 68000, and the 512K 'C00000' RAM card normally there has to come out. I also somehow recall that Dave H. decided that the buffers between the CPU and the expansion chassis needed beefing up for stability (he said this in context of the Rev 3.8/3.9 pre-production demo systems, which were derived from the German design). Not that all will have problems, but some lines could get loaded down too much and cause problems for other cards. Gary was the cost reduction chip for the A500, and Buster was the additional cost reduction chip for the A2000->B2000.

[Sanxion]

I rccently received an Amiga 2000 which has a Revision 4 board. The power supply does not work so I am in thr process of resolving that. However, the machine came with 4 expansion cards:

Zorro 8MB expansion
0.5 MB expanision
SCSI controller with a hard drive and memory
The fourth card appears to be a modem card as it has telephone inputs

I must assume therefore that "even" a Revision 4 board is comptaible with these types of expansions.

[Jope]

None of the cards listed sound like they would be incompatible with the a model.

[NorthWay]

BTW, could you take the $C00000 memory card from a 2000A and use it in a 2000B (if modded to 1M chipmem)?