[Coco] Coco 4 (Was: Test)

[Neil Morrison]

I still like the idea of an "Expansion Interface" for the Coco 3,
like the one for the Model I. Have a cable that plugs in the ROMPAK
port and use a CPU that can run a hacked version of OS-9 so that the
Coco 3 handles keyboard, screen, sound etc. and the EI does the main
computing with a better faster processor and plenty of RAM and
supports the drives, full serial and parallel ports etc. The EI can
sit under the CM-8 and hold it up a few inches.

Neil

----- Original Message ----- 
From: <jdaggett at gate.net>


> Bill
>
> The real stumbling block is to a CoCo 4 is a chip that will be
> backward compatible with the GIME Chip and improved version of
> it.
>
> If there is no need to be backward compatible with the Coco 1,2 or
3
> then a whole new chip in FPGA could be designed and go one step
> further and do the CPU in FPGA. Then you can run the whole board
> at around 25Mhz. Used SRAM and/or SDRAM.
>
> I would imagine some backward compatibility to the Coco 3 is
> needed as to not have to do major rewrites to Nitros9. Just more
> functionality of the GIME chip.
>
> james