I don’t think sourcing the old chips is really a option you can do a small production run maybe.. But if the chips are gone, your left with a new pcb design you spent a lot of hours on doing nothing.
Doing something with power pc cpu’s maybe if you have a design team behind you. It will take many many hours before it will see the light of day. Then you want to do a production run and discovery the board will be priced like the X1000 so only a small group can buy the damm thing. No.
FPGA. There is a wonderful design by yaqube and it’s here NOW. With small modifications this can be your replacement board. Print it on a larger PCB, add some ports a keyboard interface. It is possible that a second FPGA is needed to have enough IO ports and to replicate the legacy ports. But developing this is doable.
Then again why replicating the serial port, the parallel port, this can be a nice space for a USB ports. I think the PCMCIA port is a different story it’s used by many. But it’s a lot of IO stuff.
Ok.. FPGA it’s not the speed of a power pc I know but they are getting faster every year. Speeding up the custom chipset will give it a powerful boost. Even the minimig1 got a super blitter mode. Yaqube board got RTG. In the end the Amiga will be useful again do some browsing play some music, read your mail, watch a movie.
About the super agnus or replacing custom chips with FPGA’s . I think this can be a new thread, it’s a completely different story but a good one. The thing that gave us the giant leap forwards back in the days is now holding us back. We see that new games for example the port of scumm will use the chunky mode of the indivision ECS. Or the new doom that already uses this. Maybe it is possible to create a super Paula giving us 16 Bit multichannel audio. A super fast Agnus, even a RTG Lisa. But like my humble a600 your board will be taken over by al the add-ons and it will be harder and harder to get things stable. Bad chip connections for the clip-over chips etc. We already see unstable A600 accelerators in some cases, now think of making clip-on chips on every chip in you A1200.
Again A new system board, with RTG a large FPGA with enough room for future expansion is the best way to go.
