a2-liron/liron-if.asm

1333 lines
18 KiB
NASM
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2018-02-11 15:12:00 -07:00
; Apple II Liron Disk Controller Card firmware
; Firmware P/N 341-????
; Copyright 2017 Eric Smith <spacewar@gmail.com>
cpu 6502
fillto macro addr, val
while * < addr
size set addr-*
if size > 256
size set 256
endif
fcb [size] val
endm
endm
fcchz macro string
irpc char,string
fcb $80+'char'
endm
fcb $00
endm
Z00 equ $00
Z01 equ $01
mon_ch equ $24
mon_cv equ $25
checksum equ $40
Z40 equ $40
Z41 equ $41
prodos_cmd_blk equ $42
prodos_command equ $42 ; Smartport command is also copied here
prodos_unit_num equ $43
prodos_buffer equ $44
prodos_block equ $46
Z48 equ $48
Z4b equ $4b
Z4c equ $4c
Z4d equ $4d
Z4e equ $4e
Z4f equ $4f
Z50 equ $50
Z51 equ $51
Z52 equ $52
Z53 equ $53
Z54 equ $54
Z55 equ $55
Z56 equ $56
Z57 equ $57
slot equ $58
Z59 equ $59
Z5a equ $5a
Z5b equ $5b
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; per-slot screen holes (index by slot)
sh_prodos_flag equ $0478 ; MSB = 1 for ProDOS, 0 for SmartPort
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sh_04f8 equ $04f8
sh_0578 equ $0578
sh_05f8 equ $05f8
sh_0678 equ $0678
sh_magic1 equ $06f8 ; $a5 if firmware initialized
sh_magic2 equ $0778 ; $5a if firmware initialized
sh_07f8 equ $07f8
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; global screen holes - undocumented
; these seem to be used as temporaries
gh_06f8 equ $06f8
; note - 06f8 is used by Apple DOS RWTS for RECLBCNT (recal counter),
; not needed between RWTS calls
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gh_0778 equ $0778
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; global screen holes - documented
gh_shared_slot equ $07f8 ; $Cn if card in slot n $c800 ROM active
; needed for interrupt handling
D0800 equ $0800
L0801 equ $0801
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basic_cold equ $e000
mon_sloop equ $faba
mon_vtab equ $fc22
mon_cout equ $fded
mon_setkbd equ $fe89
mon_setvid equ $fe93
iwm_ph_0_off equ $c080
iwm_ph_0_on equ $c081
iwm_ph_1_off equ $c082
iwm_ph_1_on equ $c083
iwm_ph_2_off equ $c084
iwm_ph_2_on equ $c085
iwm_ph_3_off equ $c086
iwm_ph_3_on equ $c087
iwm_motor_off equ $c088
iwm_motor_on equ $c089
iwm_sel_drive_1 equ $c08a
iwm_sel_drive_2 equ $c08b
iwm_q6l equ $c08c
iwm_q6h equ $c08d
iwm_q7l equ $c08e
iwm_q7h equ $c08f
rom_dis equ $cfff
org $c000
; unknown data, not visible in Apple II address space, possibly garbage
fcb $c6,$e9,$f2,$ed,$f7,$e1,$f2,$e5
fcb $a0,$f7,$f2,$e9,$f4,$f4,$e5,$ee
fcb $a0,$e2,$f9,$a0,$cd,$e9,$e3,$e8
fcb $e1,$e5,$ec,$a0,$c1,$f3,$eb,$e9
fcb $ee,$f3,$00
fillto $c100,$ff
; Cnxx slot ROM is replicated for all seven slots, and is identical
; other than slot number references and slot I/O references
irp slotnum, 1, 2, 3, 4, 5, 6, 7
org $c000 + (slotnum << 8)
; firmware boot entry point
ldx #$20
ldx #$00
ldx #$03
cmp #$00
bcs Lcn14
prodos_entry:
sec
bcs Lcn0e
smartport_entry:
clc
; combined ProDOS/SmartPort dispatch
; save ProDOS/SmartPort flag (1 = ProDOS) in MSB of sh_prodos_flag
Lcn0e: ldx #slotnum
ror sh_prodos_flag,x
clc
; combined ProDOS/SmartPort/boot dispatch
; carry = 1 for boot, 0 for ProDOS/SmartPort
Lcn14: ldx #$c0 + slotnum
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stx gh_shared_slot
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ldx #slotnum
lda rom_dis
jmp shared_rom_entry
; shared ROM space jumps here
Lcn21: ldy #$00
lda Z4b
pha
bne Lcn2b
jmp Lcnb8
Lcn2b: lda iwm_q6l + (slotnum << 4)
bpl Lcn2b
sta Z59
lsr
lsr
lsr
and #$0f
tax
lda Z59
and #$07
sta Z59
Lcn3e: lda iwm_q6l + (slotnum << 4)
bpl Lcn3e
eor Dca27,x
sta (Z56),y
eor checksum
sta checksum
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iny
bne Lcn51
inc Z57
Lcn51: lda iwm_q6l + (slotnum << 4)
bpl Lcn51
eor Dca37,x
sta (Z56),y
eor checksum
sta checksum
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iny
Lcn60: lda iwm_q6l + (slotnum << 4)
bpl Lcn60
eor Dca47,x
sta (Z56),y
eor checksum
sta checksum
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iny
Lcn6f: lda iwm_q6l + (slotnum << 4)
bpl Lcn6f
eor Dca57,x
sta (Z56),y
eor checksum
sta checksum
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iny
bne Lcn82
inc Z57
Lcn82: ldx Z59
Lcn84: lda iwm_q6l + (slotnum << 4)
bpl Lcn84
eor Dca37,x
sta (Z56),y
eor checksum
sta checksum
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iny
Lcn93: lda iwm_q6l + (slotnum << 4)
bpl Lcn93
eor Dca47,x
sta (Z56),y
eor checksum
sta checksum
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iny
Lcna2: lda iwm_q6l + (slotnum << 4)
bpl Lcna2
eor Dca57,x
sta (Z56),y
eor checksum
sta checksum
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iny
dec Z4b
beq Lcnb8
jmp Lcn2b
Lcnb8: lda iwm_q6l + (slotnum << 4)
bpl Lcnb8
sta Z59
pla
sta Z4b
Lcnc2: lda iwm_q6l + (slotnum << 4)
bpl Lcnc2
sec
rol
and Z59
eor checksum
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Lcncd: ldy iwm_q6l + (slotnum << 4)
bpl Lcncd
cpy #$c8
bne Lcnf2
ldx Z4c
beq Lcne2
ldy #$00
Lcndc: eor (Z54),y
iny
dex
bne Lcndc
Lcne2: tax
bne Lcnf6
lda iwm_q6h + (slotnum << 4)
Lcne8: lda iwm_q7l + (slotnum << 4)
bmi Lcne8
lda iwm_ph_0_off + (slotnum << 4)
clc
rts
Lcnf2: lda #$20
bne Lcnf8 ; always taken
Lcnf6: lda #$10
Lcnf8: sec
rts
; fillto slot_fw + $fb, $ff
fcb $ff ; unused
fcb $00 ; SmartPort type
fdb $0000 ; ProDOS block count (status call required)
fcb $bf ; ProDOS characteristics
fcb prodos_entry & $0ff
endm
Sc800: jsr Scaee
jsr Sca05
ldy #$07
jsr Scba9
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lda iwm_sel_drive_2,x
lda iwm_motor_on,x
ldy #$32
Lc813: lda iwm_q7l,x
bmi Lc81f
dey
bne Lc813
sec
jmp Lc949
; send packet sync sequence
Lc81f: lda iwm_ph_0_on,x ; turn on REQ
ldy #packet_sync_sequence_len - 1
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lda #$ff
sta iwm_q7h,x ; set write mode
Lc829: lda packet_sync_sequence,y
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Lc82c: asl iwm_q6l,x
bcc Lc82c
sta iwm_q6h,x
dey
bpl Lc829
lda Z5a ; destination ID
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ora #$80
jsr send_nib7
jsr send_80 ; source address, always $80 (host)
lda Z5b ; packet type
jsr send_nib7
jsr send_80 ; aux type
jsr send_80 ; data statys byte
lda Z4c ; length of packet "odd bytes", 0-6
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ora #$80
jsr send_nib7
lda Z4b ; number of encoded 7-byte groups
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ora #$80
jsr send_nib7
lda Z4c ; any "odd bytes"?
beq Lc873 ; no, skip
; send "odd bytes"
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ldy #$ff
lda Z59
Lc862: asl iwm_q6l,x
bcc Lc862
sta iwm_q6h,x
iny
lda (Z54),y
ora #$80
cpy Z4c
bcc Lc862
; send groups
Lc873: lda Z4b ; any groups to send?
bne Lc87a ; yes
jmp send_checksum ; no
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Lc87a: nop
ldy #$00
; send a group
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Lc87d: lda Z41
sta iwm_q6h,x
lda Z4d
ora #$80
sty Z59
Lc888: ldy iwm_q6l,x
bpl Lc888
sta iwm_q6h,x
ldy Z59
lda (Z56),y
sta Z4d
asl
rol Z41
iny
bne Lc8a1
inc Z57
jmp Lc8a3
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Lc8a1: pha
pla
Lc8a3: lda #$02
ora Z41
sta Z41
lda Z4e
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z4e
asl
rol Z41
iny
lda Z4f
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z4f
asl
rol Z41
iny
lda Z50
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z50
asl
rol Z41
iny
bne Lc8dd
inc Z57
jmp Lc8df
Lc8dd: pha
pla
Lc8df: lda Z51
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z51
asl
rol Z41
iny
lda Z52
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z52
asl
rol Z41
iny
lda Z53
ora #$80
sta iwm_q6h,x
lda (Z56),y
sta Z53
asl
rol Z41
iny
dec Z4b ; sent last group?
beq send_checksum ; yes
jmp Lc87d ; no, send another group
; send checksum in FM
send_checksum:
; send checksum even bits (bit 6, 4, 2, 0)
lda checksum
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ora #$aa
; can't call send_nib7 to send the first part of the checksum, because
; it would modify the checksum in the process
Lc917: ldy iwm_q6l,x ; wait for write buffer ready
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bpl Lc917
sta iwm_q6h,x ; write data
; send checksum odd bits (bit 7, 5, 3, 1, shifted right one bit)
lda checksum
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lsr
ora #$aa
jsr send_nib7
lda #$c8 ; send packet end mark
jsr send_nib7
; wait for write underrun; IWM write state will clear when
; done writing and no data presented
Lc92c: lda iwm_q6l,x ; read IWM handshake register
and #$40 ; in write state?
bne Lc92c ; yes, loop
sta iwm_q6h,x ; prepare to read status register
ldy #$0a ; counter to wait for ACK
Lc938: dey ; timeout?
bne Lc943 ; no, go check status
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lda #$01
Sc93d: jsr get_slot_x
sec ; indicate error
bcs Lc949 ; always taken
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Lc943: lda iwm_q7l,x ; read status
bmi Lc938 ; ACK (write protect)? no, keep waiting
clc ; yes, so no error
Lc949: lda iwm_ph_0_off,x ; turn off REQ
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lda iwm_q6l,x
rts
; packet sync byte sequence, in reverse order
packet_sync_sequence:
fcb $c3,$ff,$fc,$f3,$cf,$3f
packet_sync_sequence_len equ *-packet_sync_sequence
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jsr Sc95b
nop
nop
Sc95b: nop
rts
Lc95d: jmp Sc93d
Sc960: lda #$00
sta checksum
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lda Z54
sta Z56
lda Z55
sta Z57
lda #$21 ; point Z52 at LCn21
sta Z52
lda slot
clc
adc #$c0
sta Z53
jsr Sca05
lda iwm_q6h,x
Lc97d: lda iwm_q7l,x
bpl Lc97d
lda iwm_ph_0_on,x
ldy #$1e
Lc987: lda iwm_q6l,x
bpl Lc987
dey
bmi Lc95d
cmp #$c3
bne Lc987
ldy #$06
Lc995: lda iwm_q6l,x
bpl Lc995
and #$7f
sta Z4b,y
eor #$80
eor checksum
sta checksum
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dey
bpl Lc995
lda Z4c
beq Lc9d3
clc
adc Z54
sta Z56
lda Z55
adc #$00
sta Z57
ldy #$00
Lc9b9: lda iwm_q6l,x
bpl Lc9b9
asl
sta Z41
Lc9c1: lda iwm_q6l,x
bpl Lc9c1
asl Z41
bcs Lc9cc
eor #$80
Lc9cc: sta (Z54),y
iny
cpy Z4c
bcc Lc9c1
Lc9d3: jmp (Z52)
send_80:
lda #$80
send_nib7:
ldy iwm_q6l,x
bpl send_nib7
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sta iwm_q6h,x
eor checksum
sta checksum
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rts
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Sc9e5: jsr Sca0f
lda iwm_ph_0_on,x
lda iwm_ph_2_on,x
ldy #$50
jsr Sc9f8
jsr Sca0f
ldy #$0a
Sc9f8: jsr Sc9ff
dey
bne Sc9f8
rts
Sc9ff: ldx #$c8
Lca01: dex
bne Lca01
rts
Sca05: jsr get_slot_x
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lda iwm_ph_1_on,x
lda iwm_ph_3_on,x
rts
Sca0f: jsr get_slot_x
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lda iwm_ph_0_off,x
lda iwm_ph_1_off,x
lda iwm_ph_2_off,x
lda iwm_ph_3_off,x
rts
get_slot_x:
lda slot
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asl
asl
asl
asl
tax
rts
Dca27: fcb $80,$80,$80,$80,$80,$80,$80,$80
fcb $00,$00,$00,$00,$00,$00,$00,$00
Dca37: fcb $80,$80,$80,$80,$00,$00,$00,$00
fcb $80,$80,$80,$80,$00,$00,$00,$00
Dca47: fcb $80,$80,$00,$00,$80,$80,$00,$00
fcb $80,$80,$00,$00,$80,$80,$00,$00
Dca57: fcb $80,$00,$80,$00,$80,$00,$80,$00
fcb $80,$00,$80,$00,$80,$00,$80,$00
Sca67: lda #$05
ldy #$00
jsr Sca8a
bcc Lca75
lda #$80
jsr Scded
Lca75: rts
Sca76: jsr Sca8a
bcc Lca75
lda #$80
jsr Scded
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lda gh_06f8
sta Z4d
lda gh_0778
sta Z4e
Sca8a: lda #3000 & $ff ; retry 3000 times!
ldy #3000 >> 8
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ldx slot
sta sh_04f8,x
tya
sta sh_0578,x
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Lca97: lda Z4d
sta gh_06f8
lda Z4e
sta gh_0778
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jsr Sc800
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lda gh_06f8
sta Z4d
lda gh_0778
sta Z4e
bcc Lcabc ; if no error, done
ldx slot ; decrement retry count
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dec sh_04f8,x
bne Lca97
dec sh_0578,x
bpl Lca97
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Lcabc: rts
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Scabd: ldy slot
lda #$05
sta sh_04f8,y
Lcac4: jsr Sc960
bcc Lcad8
ldy #$01
jsr Sc9f8
jsr Sc93d
ldx slot
dec sh_04f8,x
bne Lcac4
Lcad8: rts
Dcad9: fcb $00,$24,$49
Dcadc: fcb $00,$04,$01
Dcadf: fcb $00,$01,$02,$04,$09,$12
Dcae5: fcb $00,$01,$02,$04,$01,$02
Dcaeb: fcb $00,$7f,$ff
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Scaee: ldx Z4e
beq Lcb05
lda Z55
sta Z57
lda #$80
cpx #$01
beq Lcb00
inc Z57
lda #$00
Lcb00: clc
adc Z54
sta Z56
Lcb05: lda Dcad9,x
sta Z4b
lda Dcadc,x
sta Z4c
ldx #$05
lda Z4d
sta Z59
and #$07
tay
Lcb18: asl Z59
bcc Lcb31
lda Dcae5,x
Lcb1f: clc
adc Z4c
cmp #$07
bcc Lcb28
sbc #$07
Lcb28: sta Z4c
lda Dcadf,x
adc Z4b
sta Z4b
Lcb31: dex
bmi Lcb3a
bne Lcb18
tya
jmp Lcb1f
Lcb3a: lda Z55
pha
lda #$00
ldx Z4e
beq Lcb59
ldy Dcaeb,x
Lcb46: eor (Z54),y
eor (Z56),y
dey
bne Lcb46
eor (Z54),y
eor (Z56),y
cpx #$01
beq Lcb57
inc Z55
Lcb57: inc Z55
Lcb59: ldy Z4d
beq Lcb66
eor (Z54),y
Lcb5f: eor (Z54),y
dey
bne Lcb5f
eor (Z54),y
Lcb66: sta checksum
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pla
sta Z55
ldy Z4c
dey
lda #$00
sta Z59
Lcb72: lda (Z54),y
asl
ror Z59
dey
bpl Lcb72
sec
ror Z59
lda Z4c
clc
adc Z54
sta Z56
lda Z55
adc #$00
sta Z57
ldy #$06
Lcb8c: sec
lda (Z56),y
sta Z4d,y
bmi Lcb95
clc
Lcb95: ror Z41
dey
bpl Lcb8c
sec
ror Z41
lda Z56
clc
adc #$07
sta Z56
bcc Lcba8
inc Z57
Lcba8: rts
Scba9: lda iwm_motor_off,x
lda iwm_q6h,x
jmp Lcbb6
Lcbb2: tya
sta iwm_q7h,x
Lcbb6: tya
eor iwm_q7l,x
and #$1f
bne Lcbb2
rts
Scbbf: lda Z4b
tay
ldx #$00
stx Z4b
ldx #$03
Lcbc8: asl
rol Z4b
dex
bne Lcbc8
clc
adc Z4c
bcc Lcbd5
inc Z4b
Lcbd5: sty Z4c
sec
sbc Z4c
bcs Lcbde
dec Z4b
Lcbde: ldy Z4b
rts
shared_rom_entry:
bcc execute_command
jmp boot
execute_command:
cld
txa
tay
lda sh_prodos_flag,y ; ProDOS or SmartPort?
bmi Lcbff
; SmartPort
pla ; save ptr to SmartPort cmd num (offset 1)
sta sh_05f8,y
clc ; advance past cmd num and parm list ptr (low byte)
adc #$03
tax
pla ; save ptr to SmartPort cmd num (offset 1)
sta sh_0678,y
adc #$00 ; advance past cmd num and parm list ptr (high byte)
pha ; push advanced return address back onto stack
txa
pha
; ProDOS
Lcbff: php
sei
ldx #$1b
Lcc03: lda Z40,x
pha
dex
bpl Lcc03
sty slot
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lda sh_magic1,y ; has card been initialized?
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cmp #$a5
bne Lcc19
eor #$ff
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eor sh_magic2,y
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beq Lcc1e
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Lcc19: lda #$00
jsr Scded
Lcc1e: lda prodos_unit_num
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rol
php
rol
rol
plp
rol
and #$03
eor #$02
cpy #$04
bcs Lcc30
eor #$02
Lcc30: tax
inx
stx prodos_unit_num
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lda sh_prodos_flag,y ; ProDOS or SmartPort?
bpl Lcc3c
jmp Lcccf
; SmartPort command, convert it into a ProDOS command
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Lcc3c: lda sh_05f8,y ; set Z54 to point to cmd num -1
sta Z54
lda sh_0678,y
sta Z55
ldy #$01 ; copy SmartPort command
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lda (Z54),y
sta prodos_command
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iny
lda (Z54),y ; copy SmartPort arg list pointer to Z54
tax
iny
lda (Z54),y
sta Z55
stx Z54
lda #$01
ldx prodos_command ; SmartPort command in range ($00 to $09)?
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cpx #$0a
bcc Lcc62
Lcc5f: jmp Lcd9f
Lcc62: ldy #$00
lda (Z54),y
sta Z5a
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ldy #$08
Lcc6a: lda (Z54),y
sta prodos_cmd_blk,y
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dey
bne Lcc6a
lda prodos_unit_num
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bne Lcccf
ldx prodos_command
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lda Dcde3,x
and #$7f
tay
lda #$04
cpy Z5a
bne Lcc5f
cpx #$05
bne Lcc92
lda #$00
jsr Scded
Lcc8d: lda #$00
jmp Lcdc1
Lcc92: txa
bne Lccb8
lda #$21
ldx prodos_block
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bne Lcc5f
txa
ldx slot
ldy #$07
Lcca0: sta (prodos_buffer),y
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dey
bne Lcca0
lda sh_07f8,x
sta (prodos_buffer),y
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iny
lda #$00
sta (prodos_buffer),y
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lda #$08
dey
jsr Sce4f
jmp Lcc8d
Lccb8: cmp #$04
bne Lccc7
ldx prodos_block
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beq Lcccb
dex
beq Lcccb
lda #$21
Lccc5: bne Lcc5f
Lccc7: lda #$11
bne Lcc5f
Lcccb: lda #$1f
bne Lcc5f
; ProDOS
Lcccf: lda #$28
ldy slot
ldx sh_07f8,y
cpx prodos_unit_num
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bcc Lccc5
lda #$09
sta Z4d
lda #$00
sta Z4e
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sta Z55
lda #$42
sta Z54
ldx slot
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lda sh_prodos_flag,x ; ProDOS or SmartPort?
bpl Lcd02
ldx prodos_command
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lda Dcde3,x
and #$7f
sta Z5a
lda #$00
sta Z48
lda prodos_command
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bne Lcd02
sta prodos_block
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Lcd02: lda Z5a
ldx prodos_unit_num
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stx Z5a
sta prodos_unit_num
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lda #$80
sta Z5b
jsr Sca0f
jsr Sca76
bcs Lcd5c
lda prodos_buffer
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sta Z54