Re: Magic-Formel

From: Nicolas Welte (
Date: 2004-08-20 10:11:09

Marko Mäkelä wrote:
> The cartridge could do its own address decoding instead of relying on -ROML
> or -ROMH, but I can't see how it can be activated in the address space without
> asserting either -GAME or -EXROM.  One way to avoid the automatic switch to
> 64 mode would be to wait long enough after power-up before asserting -GAME
> and thus switching to the UltiMax configuration on the C64.

I think it's as easy as asserting EXROM only in the $8000-$9fff area, 
because then the C128 MMU will never see the line active, because it's 
an access in the $d5xx area.

The Retro Replay works the same way, I guess. It's also invisible on the 
C128, and only starts if you go to C64 mode.


       Message was sent through the cbm-hackers mailing list

Archive generated by hypermail pre-2.1.8.