dos33fsprogs/mist/wrong_boot2.s
2020-09-02 21:44:10 -04:00

59 lines
1019 B
ArmAsm

.byte 1 ; number of sectors for ROM to load
wboot_entry:
ldx $2B ; load slot into X
; possibly unnecessary, already there?
lda $C088,X ; turn off drive motor
; put $CX00 in $10:$11, where X is slot
; allows rebooting later
txa
lsr
lsr
lsr
lsr
ora #$c0
sta $11
lda #$00
sta $10
; make sure we are in 40col mode
; with monitor I/O working
jsr $FE89 ; SETKBD (simulate keypress?)
jsr $FE93 ; SETVID (simulate video output?)
jsr $FB2F ; INIT (clear screen/etc)
jsr $FE84 ; SETNORM (set normal video)
jsr $FC58 ; HOME (clear screen)
; print our message
ldx #$00 ; loop either 256 chars or until hit zero
loop:
lda message,X
beq done
ora #$80
jsr $FDED ; COUT
inx
bne loop
done:
; wait for keypress
jsr $fd0c ; RDKEY
; resboot from current disk (set earlier)
jmp ($0010)
message:
.byte $0D,$0D,$0D,$0D,$0D
.byte " APPLE II MYST - DISK 2",$0D,$0D,$0D
.byte " PLEASE INSERT DISK 1",$0D,$0D
.byte " PRESS ANY KEY TO REBOOT",$0D
.byte $00