I do have all the schematics for all the amigas, as well as the source for winuae. I'm not sure weather there is a open core 68020, but because the cpu will be contained within the fpga it should be quicker than the hardware version.
It needs to be cheap. The whole point of the project is to play amiga games (plus others) on a cheap handheld platform. PSP lcds are cheap, SDRAM is cheap, the fpga is around £40 ish, so i would be looking to bring it home for less than £100. I know its more than the cost of an amiga 600 on ebay, but they are getting few and far between, and are not portable.
I also want this device to play defender, pacman, frogger, etc all the games i loved playing when i was a kid. I have owned most amigas and still have 4 a500's 2 a500+'s 1 a600, 2 1200's plus loads of stuff to go with them. But i want to enjoy the games sitting in my armchair without wires.
There are other options to acomplish the same thing, but is not as much fun.
I have just developed a 48 pin device programmer, and used an arm with usb and a fpga, so i can reuse the code from the arm which has a full FAT32/16 DFS >4gig SDHC using a 30MHz bus.
It also programs the fpga using slave parellel mode which is the fastest way to do it.
One side affect from this is that after programming we have a nice 8 bit bus between the fpga and the arm, so the file system should be quick.
Designing the PCB is no problem, I am more than qualified and capable, its the HDL, i am lerning verilog at the moment for my job, but only started september, so need some help.
Its wouldn't be massive work to port minimig to the board, only a simple lcd interface and a few other bits, but then updating it to a 68020 and adding other nice bits might be some work...
As i said there are other options like using an OMAP3 600MHz arm chip and emulating the amiga but then its just another pandora.....and expensive....
I'm not sure if its even worth doing, just getting some feedback....