Re: SuperCPU for my C64 and C128

On 20/07/2018 07:11, Baltissen, GJPAA (Ruud) wrote:
> Are you sure that this happens with the SCPU as well?

It doesn't, by default it mirrors writes to the first 64k

This slows the super cpu down, because it can run software at 20mhz but 
if two writes happen one after the other then it has to wait for the 
first 1mhz write to complete.

So you can turn off mirroring of certain ranges.

http://ftp.giga.or.at/pub/c64/supercpu/superprog.html

If you add an ultimax mode then you still have to mirror ram at the 
start of memory, but you have to solve the problem of interleaving the 
1mhz vic reads into the 20mhz cpu reads.

You still need to support all the supercpu mirroring schemes as well, or 
you won't be able to get the correct timing for demo effects.