micro-sci-a2-controller/firmware/util.s

; da65 V2.11.0 - (C) Copyright 2000-2005,  Ullrich von Bassewitz
; Created:    2022-01-26 21:00:18
; Input file: xaa
; Page:       1


        .setcpu "6502"
        .org $c600

A2L      :=     $3e
MON_WAIT :=	$FCA8
GETLNZ :=	$FD67
BELL :=		$FF3A
IORTS :=        $FF58
GETNUM :=       $FFA7


        lda     #$A3            ; '#'
        sta     $33             ; set input-prompt character to '#'
LC604:  jsr     BELL
LC607:  jsr     GETLNZ          ; start new line and take input
        lda     #$00
        sta     $F2
LC60E:  sta     $C010           ; clear keyboard strobe
        sta     $F3
        ldy     $F2
        jsr     GETNUM          ; parse hex into A2, A has last char xor $b0
                                ; plus $89
        sty     $F2
        cmp     #$C6            ; $C6 from $8D (return)
        beq     LC607           ; no more input, go prompt for new input
        cmp     #$EC            ; 'S'
        beq     CMD_S
        cmp     #$F0            ; 'W'
        beq     CMD_W
        cmp     #$F3            ; 'Z'
        beq     CMD_Z
        ldy     #$7F
        cmp     #$06            ; 'M'
        beq     CMD_MX
        cmp     #$EB            ; 'R'
        beq     CMD_R
        ldx     #$06
        stx     $F3
        cmp     #$F1            ; 'X'
        beq     CMD_MX
        cmp     #$EA            ; 'Q'
        bne     LC604           ; BEEP and prompt for new input
        brk                     ; 'Q' exits out

; 'R'
CMD_R:  lda     #$50
        sta     $FC
        txa
        adc     #$00
        sta     $F3
        lda     #$00
        beq     LC651

; 'S': seek logical-track index in A2L ('22S' seeks logical track $22)
CMD_S:  lda     A2L
        asl     a
LC651:  sta     $F0
        ldy     #$FF
        bne     CMD_MX

; 'Z'
CMD_Z:  lda     A2L
        asl     a
        sta     $F1
        ldy     #$00
        beq     CMD_MX
LC660:  lda     #$50
        jsr     MON_WAIT
        sta     $C088,x
        ldy     A2L
LC66A:  jsr     MON_WAIT
        dey
        bpl     LC66A
        bmi     LC68E
LC672:  lda     #$00
        beq     LC60E

; 'W'
CMD_W:  lda     A2L
        sta     $FF
        ldy     #$0F
CMD_MX: sty     $09
        jsr     IORTS
        tsx
        lda     $0100,x
        asl     a
        asl     a
        asl     a
        asl     a
        sta     $FD
        adc     $F3
        tax
LC68E:  sta     $C089,x
        lda     $09
        beq     LC6BA
        bmi     LC6BA
        asl     a
        bmi     LC6AC
        sta     $C08F,x
LC69D:  lda     $09
        asl     a
        bmi     LC660
        nop
        nop
        lda     $FF
        sta     $C08D,x
        cmp     $C08C,x
LC6AC:  lda     $C000
        eor     #$9B
        bne     LC69D
        ldx     $FD
        sta     $C08E,x
LC6B8:  beq     LC672
LC6BA:  ldx     $FD
        sta     $C089,x
LC6BF:  ldy     $FC
LC6C1:  cpy     $F0
        bne     LC6E3
        lda     $F0
        sta     $FC
        lda     $09
        bne     LC672
        lda     $F0
        ldy     $F1
        sta     $F1
        sty     $F0
        lda     $C000
        eor     #$9B
        beq     LC6B8
        lda     #$73
        jsr     MON_WAIT
        bcs     LC6BF
LC6E3:  bcs     LC6E7
        iny
        iny
LC6E7:  dey
        tya
        and     #$03
        asl     a
        ora     $FD
        tax
        lsr     a
        lsr     a
        sta     $C081,x
        nop
        nop
        lda     #$56
        jsr     MON_WAIT
        sta     $C080,x
        bcs     LC6C1