;-------------------------------
; #RWTSSWAP
; after DOS loads, program calls
; subroutines at $BA69 and $BA7F
; to swap RWTS parameters on the
; fly
; e.g. Puzzle Master
;-------------------------------
_rwtsswap
         lda   gIsBoot0   ; if DOS 3.3 boot0 loader
         bne   rwtsswap_exit
         lda   gIsBoot1   ; and DOS 3.3 boot1 loader
         bne   rwtsswap_exit
         lda   #$04
         ldx   #$69
         ldy   #$0B
         jsr   compare    ; and T00,S04,$69 ==
         !byte $A0,07,$B9,$DF,$BC,$99,$94,$B9
         !byte $88,$10,$F7
         bcs   rwtsswap_exit
         lda   #$04
         ldx   #$7F
         ldy   #$0B
         jsr   compare    ; and T00,S04,$7F ==
         !byte $A0,07,$B9,$E7,$BC,$99,$94,$B9
         !byte $88,$10,$F7
         bcs   rwtsswap_exit
         lda   #$04
         ldx   #$69
         ldy   #$01
         jsr   modify     ; then set T00,S04,$69 =
         !byte $60
         lda   #$04
         ldx   #$7F
         ldy   #$01
         jsr   modify     ; and set T00,S04,$7F =
         !byte $60
rwtsswap_exit