Re: MMU prototyping

From: smf <smf_at_null.net>
Date: Tue, 22 May 2018 10:49:07 +0100
Message-ID: <7ec40906-bc12-acc7-2044-bc2a24edd28c@null.net>
On 22/05/2018 04:57, Jim Brain wrote:
> Doing so would mean moving the registers around a lot, since the 
> GeoRAM uses IO2 for it's registers, and IO1 for RAM.
>
> Thus, it seems more work than value for a C64 cart (one can argue the 
> same for every cart that leverages Ultimax mode, and almost none would 
> work on an Ultimax).
>
> However, a standalone cart design could easily flip the lines and 
> happy work. 

For ultimax you'd want to put georam registers in the correct place by 
decoding the address lines, instead of using IO2.

You could probably add a jumper to the cpld and tweak the logic a bit, 
but I assume you don't have an ultimax to test on anyway.

A cartridge that adds c64 compatibility to the ultimax (with a passthru) 
would be awesome, but I also think it might be impossible :D
Received on 2018-05-22 12:00:07

Archive generated by hypermail 2.2.0.