pdp data decompression routine

sub_80a116:
    php
    phb
    rep #$30
    ldy $7c
    stz $7c
    sep #$20
    stz $85
    lda $81
    pha
    plb
    ldx $7f
    jmp loc_80a2a1

sub_80a12b:
    lda [$7c],y
    iny
    bne loc_80a133
    jsr sub_80a149
loc_80a133:
    pha
    lda $85
    beq loc_80a13b
    jsr sub_80a13d
loc_80a13b:
    pla
    rts

sub_80a13d:
    dec
    sta $85
    bne loc_80a148
    lda $84
    sta $7e
    ldy $82
loc_80a148:
    rts

sub_80a149:
    inc $7e
    ldy #$8000
    rts

loc_80a14f:
    sta $7f
    asl
    bpl loc_80a176
    and #$20
    beq loc_80a168
    lda $7f
    asl
    asl
    asl
    asl
    ora #$0f
    sta $0000,x
    inx
    lda #$1f
    bra loc_80a1a0
loc_80a168:
    lda $7f
    and #$0f
    ora #$f0
    sta $0000,x
    inx
    lda #$0f
    bra loc_80a1a0
loc_80a176:
    and #$20
    beq loc_80a188
    lda $7f
    asl
    asl
    asl
    asl
    sta $0000,x
    inx
    lda #$10
    bra loc_80a1a0
loc_80a188:
    lda $7f
    and #$0f
    sta $0000,x
    inx
    lda #$00
    bra loc_80a1a0
loc_80a194:
    and #$0f
    inc
    sta $81
    jsr sub_80a12b
    cmp #$80
    bcs loc_80a14f
loc_80a1a0:
    cmp #$10
    bcc loc_80a1cc
    and #$0f
    sta $7f
loc_80a1a8:
    jsr sub_80a12b
    sta $80
    and #$f0
    ora $7f
    sta $0000,x
    inx
    dec $81
    bmi loc_80a1f3
    lda $80
    asl
    asl
    asl
    asl
    ora $7f
    sta $0000,x
    inx
    dec $81
    bpl loc_80a1a8
    jmp loc_80a2a1
loc_80a1cc:
    asl
    asl
    asl
    asl
    sta $7f
loc_80a1d2:
    jsr sub_80a12b
    sta $80
    lsr
    lsr
    lsr
    lsr
    ora $7f
    sta $0000,x
    inx
    dec $81
    bmi loc_80a1f3
    lda $80
    and #$0f
    ora $7f
    sta $0000,x
    inx
    dec $81
    bpl loc_80a1d2
loc_80a1f3:
    jmp loc_80a2a1
loc_80a1f6:
    cmp #$50
    bcc loc_80a194
    and #$0f
    sta $81
loc_80a1fe:
    lda [$7c],y
    iny
    bne loc_80a206
    jsr sub_80a149
loc_80a206:
    pha
    lda $85
    beq loc_80a20e
    jsr sub_80a13d
loc_80a20e:
    pla
    sta $0000,x
    inx
    sta $0000,x
    inx
    dec $81
    bpl loc_80a1fe
    jmp loc_80a2a1
loc_80a21e:
    lsr
    cmp #$60
    bcc loc_80a1f6
    xba
    lda [$7c],y
    iny
    bne loc_80a22c
    jsr sub_80a149
loc_80a22c:
    pha
    lda $85
    beq loc_80a234
    jsr sub_80a13d
loc_80a234:
    pla
    sta $7f
    xba
    cmp #$70
    and #$0f
    inc
    sta $81
    bcs loc_80a262
loc_80a241:
    lda $7f
    sta $0000,x
    inx
    lda [$7c],y
    iny
    bne loc_80a24f
    jsr sub_80a149
loc_80a24f:
    pha
    lda $85
    beq loc_80a257
    jsr sub_80a13d
loc_80a257:
    pla
    sta $0000,x
    inx
    dec $81
    bpl loc_80a241
    bra loc_80a2a1
loc_80a262:
    lda [$7c],y
    iny
    bne loc_80a26a
    jsr sub_80a149
loc_80a26a:
    pha
    lda $85
    beq loc_80a272
    jsr sub_80a13d
loc_80a272:
    pla
    sta $0000,x
    inx
    lda $7f
    sta $0000,x
    inx
    dec $81
    bpl loc_80a262
    bra loc_80a2a1
loc_80a283:
    bmi loc_80a21e
    lsr
    sta $81
loc_80a288:
    lda [$7c],y
    iny
    bne loc_80a290
    jsr sub_80a149
loc_80a290:
    pha
    lda $85
    beq loc_80a298
    jsr sub_80a13d
loc_80a298:
    pla
    sta $0000,x
    inx
    dec $81
    bpl loc_80a288
loc_80a2a1:
    lda [$7c],y
    iny
    bne loc_80a2a9
    jsr sub_80a149
loc_80a2a9:
    pha
    lda $85
    beq loc_80a2b1
    jsr sub_80a13d
loc_80a2b1:
    pla
    asl
    bcc loc_80a283
    bmi loc_80a2ec
    lsr
    pha
    lsr
    lsr
    inc
    sta $81
    pla
    and #$03
    xba
loc_80a2c2:
    lda [$7c],y
    iny
    bne loc_80a2ca
    jsr sub_80a149
loc_80a2ca:
    phy
    rep #$20
    sta $7f
    txa
    sec
    sbc $7f
    tay
    sep #$20
loc_80a2d6:
    lda $0000,y
    sta $0000,x
    iny
    inx
    dec $81
    bpl loc_80a2d6
    ply
loc_80a2e3:
    lda $85
    beq loc_80a2a1
    jsr sub_80a13d
    bra loc_80a2a1
loc_80a2ec:
    ror
    cmp #$e0
    bcs loc_80a311
    and #$1f
    xba
    lda [$7c],y
    iny
    bne loc_80a2fc
    jsr sub_80a149
loc_80a2fc:
    pha
    lda $85
    beq loc_80a304
    jsr sub_80a13d
loc_80a304:
    pla
    rep #$20
    asl
    sep #$20
    lsr
    xba
    inc
    sta $81
    bra loc_80a2c2
loc_80a311:
    cmp #$f0
    bcs loc_80a355
    and #$0f
    sta $80
    lda [$7c],y
    iny
    bne loc_80a321
    jsr sub_80a149
loc_80a321:
    pha
    lda $85
    beq loc_80a329
    jsr sub_80a13d
loc_80a329:
    pla
    sta $7f
    lda [$7c],y
    iny
    bne loc_80a334
    jsr sub_80a149
loc_80a334:
    phy
    pha
    pha
    rep #$20
    lda $7f
    clc
    adc #$0003
    lsr
    tay
    pla
loc_80a342:
    sta $0000,x
    inx
    inx
    dey
    bne loc_80a342
    sep #$20
    bcc loc_80a352
    sta $0000,x
    inx
loc_80a352:
    ply
    bra loc_80a2e3
loc_80a355:
    cmp #$f8
    bcs loc_80a372
    and #$07
    adc #$02
    sta $81
    lda [$7c],y
    iny
    bne loc_80a367
    jsr sub_80a149
loc_80a367:
    sta $0000,x
    inx
    dec $81
    bpl loc_80a367
    jmp loc_80a2e3
loc_80a372:
    cmp #$fc
    bcs loc_80a3bf
    and #$03
    xba
    lda [$7c],y
    iny
    bne loc_80a381
    jsr sub_80a149
loc_80a381:
    rep #$20
    asl
    asl
    asl
    sep #$20
    lsr
    lsr
    lsr
    xba
    pha
    lda [$7c],y
    iny
    bne loc_80a395
    jsr sub_80a149
loc_80a395:
    rep #$20
    clc
    adc #$0003
loc_80a39b:
    sty $82
    sta $7f
    sep #$20
    lda $7e
    sta $84
    rep #$20
    tya
    sec
    sbc $7f
    bmi loc_80a3b3
    clc
    adc #$8000
    dec $7e
loc_80a3b3:
    tay
    sep #$20
    pla
    clc
    adc #$03
    sta $85
    jmp loc_80a2a1
loc_80a3bf:
    cmp #$fe
    bcs loc_80a3e2
    and #$01
    xba
    lda [$7c],y
    iny
    bne loc_80a3ce
    jsr sub_80a149
loc_80a3ce:
    rep #$20
    asl
    asl
    sep #$20
    xba
    pha
    xba
    lsr
    lsr
    rep #$20
    and #$003f
    inc
    inc
    bra loc_80a39b
loc_80a3e2:
    plb
    plp
    rtl