Emulate RAM/ROM Using Raspi Pico and a 68K

[ErBo32]

I can't find this topic on this forum and so I give it a shot myself.

Press a 68000 or a 68008 into a breadboard and knot it up to a Raspi Pico. Seems simple and it is more simple than one might think. At least to do some simple coding.
I don't know yet if a 68K can do single stepping but a W65C02S does.

See this wonderfull example:
Build Your Own Computer - Emulate RAM/ROM For A 6502 Using a Raspberry Pi Pico
https://www.youtube.com/watch?v=elrf1nM5nco

The RAM is present in the Pico and the ROM is to copy into a second part of the Pico's RAM. Just do allocate and there you go.

I don't know exactly about certain hardware addresses and how to fabricate a screen. In theory even a Raspberry Pi model 4 or 5 could do it and then there is a keyboard and SDcard and the screen output would not be a problem. Have to find out. Had some experience with programming in X11 and it is easy to put anything on screen in any dimension. I would try first the example with the W65C02S on the Pico. Someone in the comments says he reached 2 MHz with better sofware than the example. If done in C it may go higher.

If possible it would be cheap and small. Who wouldn't like such a pretty treasure?

Has anyone already been trying this, or thinking about it?
Would like to hear about the result.

[tofro]

Have a look here, this is to a big part what you are trying to achieve (just with a bit different kind of silicon).

[ErBo32]

Very nice job
But without a easy way to have a good screen
Have to find a way to use the gpio pins of a raspberry pi 4 or 5
Maybe via i2c and a line of shift registers on high speed
The 8 bits databus and some control pins need two-way communication so it needs 2 x two 74HC145 buffers in antiparallel
If that works then no limits to a screen and no need to its own SDcard

[Derek_Stewart]

Hi

Have you seen this:
https://hackaday.com/2024/11/05/picorom ... -emulator/