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nes-proj/backyard/platform/c64/loader/c64-dio-asm.S

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Added assembler code files that were left out of the code import
2006-06-18 07:45:36 +00:00
.export _c64_dio_asm_init
.export _c64_dio_asm_read_block
.export _c64_dio_asm_write_block
.export _c64_dio_asm_track, _c64_dio_asm_sector
.export _c64_dio_asm_ptr
.importzp ptr1, ptr2
;; job code $80 read, $90 write
ciout = $ffa8
listen = $ffb1
second = $ff93
unlsn = $ffae
nbytes = 34
esc = $42
blockread = 1
blockwrite = 2
errok = 0
errerr = 1
.data
_c64_dio_asm_track: .byte 0
_c64_dio_asm_sector: .byte 0
_c64_dio_asm_ptr: .byte 0,0
.code
;---------------------------------------
_c64_dio_asm_read_block:
lda #blockread
jsr send
lda _c64_dio_asm_track
jsr send
lda _c64_dio_asm_sector
jsr send
jsr recv
cmp #errok
bne readerr
lda _c64_dio_asm_ptr
sta ptr1
lda _c64_dio_asm_ptr+1
sta ptr1+1
ldy #0
readl:
jsr recv
sta (ptr1),y
iny
bne readl
clc
lda #0
tax
rts
readerr:
; sta $07c0
jsr recv
; sta $07c1
ldx #0
rts
;---------------------------------------
_c64_dio_asm_write_block:
lda #blockwrite
jsr send
lda _c64_dio_asm_track
jsr send
lda _c64_dio_asm_sector
jsr send
lda _c64_dio_asm_ptr
sta ptr1
lda _c64_dio_asm_ptr+1
sta ptr1+1
ldy #0
writel:
lda (ptr1),y
jsr send
iny
bne writel
jsr recv
cmp #errok
bne writeerr
lda #0
tax
rts
writeerr:
; sta $07c0
jsr recv
; sta $07c1
ldx #0
rts
;---------------------------------------
_c64_dio_asm_init:
sta devnr
lda #$00
sta drvmem
lda #$05
sta drvmem+1
lda #<drive
sta ptr1
lda #>drive
sta ptr1+1
; lda devnr
; ldx #<icmd
; ldy #>icmd
; jsr drvcmd
; jsr unlsn
mwl:
lda devnr
ldx #<mwcmd
ldy #>mwcmd
jsr drvcmd
ldy #0
lda (ptr1),y
jsr ciout
iny
cpy #nbytes
bne *-8
jsr unlsn
lda drvmem
clc
adc #nbytes
sta drvmem
lda drvmem+1
adc #0
sta drvmem+1
lda ptr1
clc
adc #nbytes
sta ptr1
tax
lda ptr1+1
adc #0
sta ptr1+1
cpx #<driveend
sbc #>driveend
bcc mwl
lda devnr
ldx #<mecmd
ldy #>mecmd
jsr drvcmd
jsr unlsn
rts
;---------------------------------------
drvcmd:
stx ptr2
sty ptr2+1
jsr listen
lda #$6f
jsr second
ldy #0
lda (ptr2),y
sta drvcmdcmp+1
inc ptr2
bne *+4
inc ptr2+1
ldy #0
lda (ptr2),y
jsr ciout
iny
drvcmdcmp: cpy #0
bne *-8
rts
;---------------------------------------
devnr: .byte 8
mwcmd: .byte 6
.byte $4d, $2d, $57
drvmem: .word $0500
.byte nbytes
.byte 0
mecmd: .byte 2
.byte $55, $33
.byte 0
;---------------------------------------
send:
sta ptr2
ldx #7
sendl:
lsr ptr2
lda $dd00
and #$df
ora #$10
bcc *+4
eor #$30
sta $dd00
lda #$c0
bit $dd00
bne *-3
lda $dd00
and #$cf
sta $dd00
lda $dd00
and #$c0
eor #$c0
bne *-7
dex
bpl sendl
ldx $d020
lda #1
sta $d020
stx $d020
rts
;---------------------------------------
recv:
ldx $d020
lda #0
sta $d020
stx $d020
ldx #7
recvl:
lda $dd00
and #$c0
eor #$c0
beq *-7
asl a
lda $dd00
and #$df
ora #$10
bcs *+4
eor #$30
sta $dd00
ror ptr2
lda #$c0
bit $dd00
beq *-3
lda $dd00
and #$cf
sta $dd00
dex
bpl recvl
lda ptr2
rts
;---------------------------------------
;---------------------------------------
;the code residing in the drive:
;---------------------------------------
dtmp = $46
dtmp2 = $97
dbuf = $0300
dbufcmd = $00
dbuftrack = $06
dbufsect = $07
retries = 4
bretries = 2
;---------------------------------------
drive :
.org $0500
cld
tsx
stx dstack
sei
jsr ledoff
drivel:
jsr dload
jsr ledoff
cli
jmp drivel
;---------------------------------------
ledon:
lda $1c00
ora #$08
sta $1c00
rts
ledoff:
lda $1c00
and #$f7
sta $1c00
rts
;---------------------------------------
drecv:
ldx #7
drecvl:
lda $1800
bmi atn
and #5
beq *-7
lsr a
lda #2
bcc *+4
lda #8
sta $1800
ror dtmp
lda $1800
bmi atn
and #5
eor #5
beq *-9
lda #0
sta $1800
dex
bpl drecvl
lda dtmp
rts
;---------------------------------------
atn:
ldx dstack
txs
cli
rts
;---------------------------------------
dsend:
sta dtmp
ldx #7
dsendl:
lsr dtmp
lda #2
bcs *+4
lda #8
sta $1800
lda $1800
bmi atn
and #5
eor #5
bne *-9
sta $1800
lda #5
bit $1800
bne *-3
dex
bpl dsendl
rts
;---------------------------------------
dload:
ldy #0
jsr drecv
sta dcmd
jsr ledon
jsr drecv
sta dbuftrack
jsr drecv
sta dbufsect
lda dcmd
cmp #blockwrite
bne dblockread
dblockwrite:
ldy #0
drecvpl:
jsr drecv
sta dbuf,y
iny
bne drecvpl
jmp dputsect
dblockread:
jsr dgetsect
dsendpage:
ldy #0
dsendpl:
lda dbuf,y
jsr dsend
iny
bne dsendpl
rts
;---------------------------------------
dgetsect:
; stx dbuftrack
; sty dbufsect
ldx #retries
dgetsectl:
lda #$80
sta dbufcmd
cli
:
lda dbufcmd
bmi :-
sei
cmp #1
beq dgsnoerr
cpx #0
beq dgsserr
dex
cpx #bretries
bcs dgetsectl
pha
lda #$c0
sta dbufcmd
cli
:
lda dbufcmd
bmi :-
pla
cpx #0
bne dgetsectl
dgsserr:
pha
lda #errerr
jsr dsend
pla
jsr dsend
rts
dgsnoerr:
lda #errok
jsr dsend
rts
;---------------------------------------
dputsect:
; stx dbuftrack
; sty dbufsect
ldx #retries
dputsectl:
lda #$90
sta dbufcmd
cli
:
lda dbufcmd
bmi :-
sei
cmp #1
beq dpsnoerr
cpx #0
beq dpsserr
dex
cpx #bretries
bcs dputsectl
pha
lda #$c0
sta dbufcmd
cli
:
lda dbufcmd
bmi :-
pla
cpx #0
bne dputsectl
dpsserr:
pha
lda #errerr
jsr dsend
pla
jsr dsend
rts
dpsnoerr:
lda #errok
jsr dsend
rts
;---------------------------------------
led: .byte 0,0
dstack: .byte 0
dcmd: .byte 0
.RELOC
driveend:
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