----- Original Message ----- From: "Marko Mäkelä" <firstname.lastname@example.org> > Oh, now I got it: you use the zero page or stack page relocation register > and write the data to $100-$104 or to $00-$04 (well, I guess it's easier > for you to write to $100 or $101 than to $00 or $01 (I've done the latter > without using the MMU)). > Marko- I like the idea. I was wondering if the zero page relocation register would work for $00 and $01 of the $ff00/$ff01 registers? According to my Mapping the C128, all references to $00 and $01 would go to the true $00/$01 of the 8502's I/O ports. I think that the following code would not work: lda #value sta $00 ; sta $ff00 lda #value sta $01 ; sta $ff01 But, would the following code work? ldx #$01 lda #value sta $ff,x ; sta $ff00 inx lda #value sta $ff,x ; sta $ff01 By indirectly accessing $00 and $01 using the wraparound feature of the 65xx CPU, would this method work with a relocated zero page in a C128 system? If that doesn't work, then the relocatable stack should work in accessing the ram underneath $ff00-$ff04. Thanks, -Todd Elliott Message was sent through the cbm-hackers mailing list
Archive generated by hypermail 2.1.1.