A4000TX ATX Amiga motherboard

Morning thoughts, please apologize if any of those are completely insane :)

PS2 for Amiga/PC keyboard - OK
But PS2 for PC mouse - its very outdated, I would better see there USB HID solution.

Check this:
http://centuriontech.eu/product/a1200-usb-mouse-module/

Its based on this project
https://github.com/simoninns/SmallyMouse2

There are USB keyboard solutions for A1200 but I don't remember something like that for A4000.


Cosmos made several improvements and this would be useful to integrate - PIO2 and 4MB ROM
http://leblogdecosmos.blogspot.com/2017/08/ramy-arrivee.html


CF/SD I don't know how complicated it could be to integrate. We can talk further about integrated IDE2SATA...
Same way memory - simple way to replace those pesky SIMM sockets with single memory chip on board?
What about IO socket where one would just plug RapidRoad (similar way you connect it to X-Surf 100) and you have ready to go AMIGA USB solution...

Integration of PCI slots would the craziest thing by far.
1) http://krashan.ppa.pl/articles/prometheus/ (opensource but lack of sw support)
2) Elbox mediator (best sw support but It would need vendor support)

Is 68030 CPU onboard mandatory for 4000D rev D board? And that way we can remove onboard Fast RAM completely.
[h=1][/h]
 
Putting this in a checkmate 1500 or probably in one of the next kickstarters of a1200.net, this will be amazing.

Not gonna work, this PCB is too big. Checkmate is MicroATX and putting it in a new wedge case doesn't make sense not just from size perspective.

As I said on a different forum. If I would have a chance to get this board and find a volunteer to populate it, it would be cool to also have some USB sockets to connect your Zorro USB card to, saves a bracket. Although, judging from the pictures there are more rows availavle in a typical case than there are zorro slots, so making USB sockets not so needed after all.

Integration of PCI slots would the craziest thing by far.
1) http://krashan.ppa.pl/articles/prometheus/ (opensource but lack of sw support)
2) Elbox mediator (best sw support but It would need vendor support)

Yes, that would be awesome. I'm curious how passive/active a mediator daughter board is. If it is simply just a A4000 daughter board with ISA replaced by PCI (and a bus connecting the PCI slots) and the real "magic" is all located on the mediator bridge/logic board, then maybe, just very maybe, making an a4000TX with PCI instead of ISA is a possibility.
 
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Great work! The board layout looks very fine!

Some minor hints: You should think of putting the IDE-GALs in THT sockets. SMD-Sockets are poor to solder by hand. THT are much more robust. If the IDE-GALs are removable you could easily play with the PIO2-hacks, which are sometimes incompatible with some accelerator boards. Therefore a "roll back"-option should be considered.

What about the ATX-Power-On? Modern ATX have a push-button instead of a classic switch. Is there a flipflop/NE555-trigger or similar to use a ATX-Case pushbutton instead of a switch for power-on?

The Zorro-Termination with resistior-arrays is a bad sollution by commo. They become very hot and are waisitng only energy! Im working on a busboard with a simple 1117-Line regulator and some series of resistors to make this terminator "active" like active SCSI-terminators. But this is still work in progress.

What about a 5th Zorro-Slot? All signals are present ;) --oops- ATX-form factor exceeded. Forget my remark!

Again: Great work! (y)
 
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Fabulous. Simply that.

It appears to me, that there are at least 4 people doing some incredible work on re-creating Amiga motherboards at the moment, adding things, removing unnecessary things. The community appreciates it, and it's easy for me to say it's a shame that, although you may be in contact/know of each other, that you're not working together with the same goal/targets. The community support is out there. You could see that just for cases.
 
A PCB for the sake of a PCB to frame would be my interest. Lots of other work beyond my (current) ability to complete it in a timely manner being the reason, plus having a functional A4000T means it is a backup PCB in case the worst happens. Very nice work.

The wish list I'd put up for general consideration would be to push the ROM size limit to allow 1MB (employ ROMY - Std @ F8 and Extended @ E0). Raise the motherboard RAM limit to 64MB (drop 1MB SIMM support, add 4x 16MB SIMM support, or a double-bank of 2x 32MB; keep 4x 4MB/2x 8MB SIMM support). Both of these are out there as far as how-to/wiring.

I look to the IDE and wonder what can be done there to make it a decade more modern for a modest amount of effort. Be it a higher PIO, or just easier to connect multiple (modern) devices without the legacy hard wiring of Master/Slave which tends to be needed (Maybe just multiple headers and a jumper to mark the master/force slave to solve the issue). If you have the resources to pull some/most of the custom GAL logic and some generic TTL to a reasonably available gate array in this zone, this might leave room for improvement (by you or others?) over the current implementation sometime down the road.

I want to see a CPU-offload (meaning it's own processor) high performance NIC - one that does all the work (from checksum and IP stack overhead, to DMA to destination) before the data is presented to the application. This is in the spirit of Amiga - let custom processors do what is inefficient for the core CPU or bus to be handling - but is outside of the scope of basic motherboard adjustments like you might easily do. More for others to ponder.

Interest in a PCB (no parts) if you are counting.
 
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I do want one of these!.. It doesn't matter either a working prototype or a final product.
 
Amazing work! :D

I feel bad for coming with comments but here they are anyways:

1, How much space could you save by not including the MC68030 and FPU unit? I know that will probably require a fairly major redesign. That would probably give you another slot. Or...
2, Can the Zorro connectors be be broken out and put on a daughter board? Making the board instead, So the mb will be a regular ATX board. And connected with a ribbon cable to the daughter board. That will also allow you to mount the cards in those vertical slots that cases now a days really like to have.
3, Does it come in black? ;)
 
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Great work, impressive. Will it be a good idea to include 64 MB Fast RAM modification, it only requires some re-routing and no extra components?
 
This is a great board Hese!

When a suggestion is welcome I would remove the 3 ISA slots and replace them with PCI ones. Then we could install a
Mediator PCI 4000 MK-III Core Logic card for activation of the PCI slots.
 
Fascinating. Great work done here.

Question: obviously, a donor machine would be required to get the custom chips. Would a 1200 have everything required? IE, can we upgrade from a 1200 to this board?


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