stella/test/roms/bankswitching/_code/F4.asm

382 lines
3.0 KiB
NASM

;;A demo for the F4 banking scheme. 8 4K banks (32K total)
;;By: Rick Skrbina 3/31/09
processor 6502
include "vcs.h"
include "macro.h"
seg.u vars
org $80
seg bank0
org $8000
rorg $F000
Start0
nop
nop
nop
CLEAN_START
Start_Frame
lda #2
sta VBLANK
sta VSYNC
sta WSYNC
sta WSYNC
sta WSYNC
lsr
sta VSYNC
lda #$0F
sta COLUBK
ldy #37
VerticalBlank
sta WSYNC
dey
bne VerticalBlank
lda #0
sta VBLANK
sta WSYNC
ldy #23
Picture0
sta WSYNC
dey
bne Picture0
jsr Swch1
ldy #23
Picture1
sta WSYNC
dey
bne Picture1
jsr Swch2
ldy #23
Picture2
sta WSYNC
dey
bne Picture2
jsr Swch3
ldy #23
Picture3
sta WSYNC
dey
bne Picture3
jsr Swch4
ldy #23
Picture4
sta WSYNC
dey
bne Picture4
jsr Swch5
ldy #23
Picture5
sta WSYNC
dey
bne Picture5
jsr Swch6
ldy #23
Picture6
sta WSYNC
dey
bne Picture6
jsr Swch7
ldy #23
Picture7
sta WSYNC
dey
bne Picture7
lda #2
sta VBLANK
ldy #30
OverScan
sta WSYNC
dey
bne OverScan
jmp Start_Frame
org $8FC0
rorg $FFC0
Swch7
lda $FFFB
nop
nop
nop
nop
nop
nop
rts
org $8FD0
rorg $FFD0
Swch1
lda $FFF5
Swch2
lda $FFF6
Swch3
lda $FFF7
rts
rts
rts
rts
rts
rts
rts
org $8FE0
rorg $FFE0
Swch4
lda $FFF8
Swch5
lda $FFF9
Swch6
lda $FFFA
rts
rts
rts
rts
rts
rts
rts
org $8FFC
rorg $FFFC
.word Start0
.byte "B0"
seg bank1
org $9000
rorg $F000
Start1
lda $FFF4
Bank1Sub
lda #$1F
sta WSYNC
sta COLUBK
rts
org $9FD0
rorg $FFD0
nop
nop
nop
jsr Bank1Sub
sta $FFF4
org $9FFC
rorg $FFFC
.word Start1
.byte "B1"
seg bank2
org $A000
rorg $F000
Start2
lda $FFF4
Bank2Sub
lda #$2F
sta WSYNC
sta COLUBK
rts
org $AFD0
rorg $FFD0
nop
nop
nop
nop
nop
nop
jsr Bank2Sub
sta $FFF4
org $AFFC
rorg $FFFC
.word Start2
.byte "B2"
seg bank3
org $B000
rorg $F000
Start3
lda $FFF4
Bank3Sub
lda #$3F
sta WSYNC
sta COLUBK
rts
org $BFD0
rorg $FFD0
nop
nop
nop
nop
nop
nop
nop
nop
nop
jsr Bank3Sub
sta $FFF4
org $BFFC
rorg $FFFC
.word Start3
.byte "B3"
seg bank4
org $C000
rorg $F000
Start4
lda $FFF4
Bank4Sub
lda #$4F
sta WSYNC
sta COLUBK
rts
org $CFE0
rorg $FFE0
nop
nop
nop
jsr Bank4Sub
sta $FFF4
org $CFFC
rorg $FFFC
.word Start4
.byte "B4"
seg bank5
org $D000
rorg $F000
Start5
lda $FFF4
Bank5Sub
lda #$5F
sta WSYNC
sta COLUBK
rts
org $DFE0
rorg $FFE0
nop
nop
nop
nop
nop
nop
jsr Bank5Sub
sta $FFF4
org $DFFC
rorg $FFFC
.word Start5
.byte "B5"
seg bank6
org $E000
rorg $F000
Start6
lda $FFF4
Bank6Sub
lda #$6F
sta WSYNC
sta COLUBK
rts
org $EFE0
rorg $FFE0
nop
nop
nop
nop
nop
nop
nop
nop
nop
jsr Bank6Sub
sta $FFF4
org $EFFC
rorg $FFFC
.word Start6
.byte "B6"
seg bank7
org $F000
rorg $F000
Start7
lda $FFF4
Bank7Sub
lda #$8F
sta WSYNC
sta COLUBK
rts
org $FFC0
rorg $FFC0
nop
nop
nop
jsr Bank7Sub
sta $FFF4
org $FFFC
rorg $FFFC
.word Start7
.byte "B7"