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But PS2 for PC mouse - its very outdated, I would better see there USB HID solution.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