Potential add-on board?

[billt]

What will comnect to what? Cpu slot to usb2? maybe enough gpio to make a "software bus" but that wound not likely perform well. I made apb and ahb bus before on gpio, was very slow but suitable for the unusual situation at hand. Ibwouldnt do this for something in the real world.

[billt]

The Compute Module has the same form factor as a DDR2 SODIMM, so can be connected to Amiga buses.

What pins of that compute module will connect to what in the Amiga? There is not an exposed memory bus. There is a USB2, there is a number of GPIO, but nothing tha tI see as a good connection between them.

[billt]

The GPIO pins are also connected to BCM ARM peripherals, for example i2c/spi etc.
SMI is one of these peripherals designed to connect to multiplexed address/data buses.
It can spit out some data at high speed, and a simple FPGA can then act as an interface to the 68K socket.

I'll post more on the fpgaarcade.com forum as I make progress.

Ah, I had overlooked SMI before. 16bit data, OK for 68000 socket I guess. I only see 6 address bits though. Can likely use other GPIOs for irq inputs. Am I missing something, or is it that limited?