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aiie/tests/diskii-woz-test.asm

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.feature labels_without_colons
.feature leading_dot_in_identifiers
.feature c_comments
.P02 ; normal 6502
.macro ADR val
.addr val
.endmacro
.macro BLT val
BCC val
.endmacro
.macro BGE val
BCS val
.endmacro
; Force APPLE 'text' to have high bit on; Will display as NORMAL characters
.macro ASC text
.repeat .strlen(text), I
.byte .strat(text, I) | $80
.endrep
.endmacro
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.struct iob_t
type .byte ; table type (always $01)
slot .byte ; slot (<<4)
drive .byte ; drive (1/2)
volume .byte ; volume ($00 = all)
track .byte
sector .byte
dct .word ; low/hi pointer to a DCT
data .word ; low/hi pointer to sector data
unused .word
bytes .word ; # bytes to read/write ($00 == 256)
command .byte ; 0=seek, 1=read, 2=write, 4=fmt
retval .byte ; return code
retvol .byte ; return volume
retslot .byte ; return slot
retdrive .byte ; return drive
.endstruct
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a_cr = $0d ; Carriage return.
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RWTS_GETIOB = $03E3 ; low returned in Y, high A ($B7E8 is the normal IOB)
RWTS = $03D9 ; needs IOB address in Y/A
DOS33_IOB = $B7E8
IOB = DOS33_IOB
DOS33_SECBUF = $B4BB ; $B4BB-B5BA
RWTS_WRTDIR = $B037 ; hidden routine in DOS to call RWTS (cf. AAL Vol2, iss 8)
RWTS_WRTCMD = $B041 ; ... which wants to call write by default and we modify it to do something else
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F8ROM_YXHEX = $F940
F8ROM_AXHEX = $F941
F8ROM_XHEX = $F944 ; print X register in hex -- kills X,A
F8ROM_AHEX = $FDDA ; print A register in hex
F8ROM_INIT = $FB2F
F8ROM_HOME = $FC58 ; Kills A,Y
F8ROM_CROUT = $FC62 ; carriage return out
F8ROM_MONWAIT = $FCA8 ; wait for (A*A*2.5 + A*13.5 + 7) * 0.980 usec
F8ROM_COUT = $FDED ; Load A with character to print
F8ROM_RDKEY = $FD0C
WRVEC = $03D0 ; warm re-entry point
PHSOFF = $C080
PHSON = $C081
DISKOFF = $C088
DISKON = $C089
DRIVEA = $C08A
DISK_LATCHR = $C08C
DISK_LATCHW = $C08D
DISK_MODER = $C08E
DISK_MODEW = $C08F
;; Zero-page addresses used
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;; Totally free and clear: 6,7,8,9; eb,ec,ed,ee,ef;fa,fb,fc,fd
ZP_STORPTR = $06 ;06,07
ZP_STOR2 = $08 ;08,09
ZP_SCRATCH = $eb ;just eb
ZP_TRANSP = $ec ;ec,ed
DST = $ee ;ee,ef
ZP_SECTP = $fa ;fa,fb
ZP_PRINT = $fc ;fc, fd
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.segment "CODE"
START
JMP Entry
Entry
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PHP ;save interrupt state
SEI ;disable interrupts
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JSR F8ROM_INIT
JSR F8ROM_HOME
JSR Prtmsg
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ASC "Insert a blank floppy in s6d1 and press a key..."
.byte $8D, $00
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JSR F8ROM_RDKEY ; wait for a keypress
;; set up pointers to SECDATA and TRANS62
LDA #>SECDATA
STA ZP_SECTP+1
LDA #<SECDATA
STA ZP_SECTP
LDA #>TRANS62 ; set up ZP_TRANSP to point at TRANS62
STA ZP_TRANSP+1 ; (a 64-byte lookup table)
LDA #<TRANS62
STA ZP_TRANSP
;; initialize the buffer to start, so we can see what's going on
;; DEBUGGING *** - don't really need to do this
LDA #$FE
STA VALUE
LDA #>NYBDATA
STA DST+1
LDA #<NYBDATA
STA DST
LDA #$00
STA CNT
LDA #$1A
STA CNT+1
JSR memset
;; Turn on motor for slot 6, drive 1
LDX #$60 ; slot 6
LDA DISKON,X
LDA DRIVEA,X
;; and seek out to track 0
JSR RecalibrateTrack
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;; Wait for it to come to speed
JSR WaitMotor
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;; write 40 tracks of data
LDA #$00
@writeAnotherTrack
JSR WriteOneTrack ; takes track number in A and preserves it
CLC
ADC #1
CMP #35
BNE @writeAnotherTrack
;; Turn off motor for slot 6, drive 1 and let RWTS turn it back on
LDX #$60 ; slot 6
LDA DISKOFF,X
@rwtstest
;; using RWTS, validate the sector contents of each sector on the track
;;
;; call RWTS to perform the read
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;; Reset the current track
JSR RecalibrateTrack
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;; Let RWTS think we're changing slots, so it doesn't use any cached
;; data about the head position
LDA #$70
STA DOS33_IOB+iob_t::retslot
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LDA #01
STA RWTS_WRTCMD ; set read command
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;; Pick track/sector to read
LDA #$00
STA $B397 ; track
LDA #$00
STA $B398 ; sector
@readAnotherSector
LDA $B397
JSR F8ROM_AHEX
LDA $B398
JSR F8ROM_AHEX
JSR Prtmsg
ASC " :Reading track/sector"
.byte $00
JSR RWTS_WRTDIR
;; check for an error (detail is in IOB + $0D)
BCC @noErrors
JMP rwtsTestsFailed
@noErrors
;; Generate the expected block of data so we can validate the sector
LDA $B397
STA TARGETTRK
LDA $B398
STA TARGETSEC
JSR MakeSectorData
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;; compare SECDATA against the RWTS sector buffer at DOS33_SECBUF
LDA TARGETSEC
JSR F8ROM_AHEX
JSR Prtmsg
ASC " : validate sector contents"
.byte $00
JSR Seccmp
BCC @cmpok
JMP FailedSectorCompare
@cmpok
;; *** Something is wrong with the IOB+iob::sector approach -- if I hard code addresses for track/sector this works, but if I use the :: struct mechanism is doesn't
;; *** ... and the T/S offsets don't match the IOB header, so I'm not
;; *** sure why storing them at these addresses works - need more
;; *** RWTS info
;; *** https://www.txbobsc.com/aal/1982/aal8205.html#a6
;; Read the next sector
INC $B398
LDA $B398
CMP #$10
BEQ @nextTrack
JMP @readAnotherSector
@nextTrack
LDA #$00
STA $B398
INC $B397
LDA $B397 ;track
CMP #$23
BEQ @doneReadTest
JMP @readAnotherSector
@doneReadTest
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;; Find sector # 6 (arbitrarily chosen) and replace its data
;; with 256 bytes of 0xFF (nybbles 0xFF 0x96 0x96 0x96 ... )
;; ...
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;; using RWTS, validate the sector contents of all 16 sectors again
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;; ...
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TestsDone
JSR Prtmsg
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ASC "Test complete, no errors found."
.byte $00
Exit
PLP ;restore interrupts
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LDA #$00
STA $48 ; RWTS: needs to be cleared after calls
;; for debugging, show where the sector and nybble data are
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LDA #>SECDATA
JSR F8ROM_AHEX
LDA #<SECDATA
JSR F8ROM_AHEX
JSR Prtmsg
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ASC " : sector data buffer"
.byte $00
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LDA #>NYBDATA
JSR F8ROM_AHEX
LDA #<NYBDATA
JSR F8ROM_AHEX
JSR Prtmsg
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ASC " : nybble data buffer"
.byte $00
;; Fix DOS where we butchered it
LDA #02
STA RWTS_WRTCMD ; reset command to original value ("write")
;; Turn off motor for slot 6, drive 1 before exiting
LDX #$60 ; slot 6
LDA DISKOFF,X
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JMP WRVEC ; done; warm-start for the user
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rwtsTestsFailed
LDA IOB+iob_t::retval ; get return code from our IOB
JSR F8ROM_AHEX ; print it
JSR Prtmsg
ASC " : error reported during RWTS... stopping"
.byte $00
JMP Exit
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WriteProtected
JSR Prtmsg
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ASC "Disk is write protected; aborting"
.byte $00
JMP Exit
FailedSectorCompare
JSR Prtmsg
ASC "Sector comparison failed"
.byte $00
JMP Exit
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;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Start of subroutines
;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; Prtmsg: display text on screen, using inline
;; null-terminated strings. Trashes A,X,Y, ZP_PRINT, ZP_PRINT+1.
;; Adds a newline at the end of the string. Strings may be
;; arbitrarily long. Expects the string to have the high bit
;; set where necessary; passes the characters directly to COUT.
Prtmsg
PLA
STA ZP_PRINT
PLA
STA ZP_PRINT+1
LDY #$00
@LoopA
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INY
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BNE @noinc
INC $FD
@noinc
TYA
PHA
LDA (ZP_PRINT),Y
BEQ @done
JSR F8ROM_COUT
PLA
TAY
JMP @LoopA
@done
PLA
CLC
TYA
ADC ZP_PRINT
TAX
LDA ZP_PRINT+1
ADC #$00
PHA
TXA
PHA
JSR F8ROM_CROUT
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RTS
;; WaitMotor: delay to wait for a drive to come up to speed
WaitMotor
LDA #$EF
STA WAITCTR
LDA #$D8
STA WAITCTR+1
@LoopA LDY #$12
@LoopB DEY
BNE @LoopB
INC WAITCTR
BNE @LoopA
INC WAITCTR+1
BNE @LoopA
RTS
;; MoveTrack: move from CURHALFTRK to DSTHALFTRK
;; Note that those are (as the names imply) half-tracks; be
;; sure to multiply actual track numbers by two
MoveTrack
LDA CURHALFTRK
CMP DSTHALFTRK
BNE @MoreWork
RTS ; all done, return
@MoreWork
BCC @MoveUp ; If we want to move up, then go there
;; otherwise fall through to movedown
@MoveDown
DEC CURHALFTRK
JMP @MoveHead
@MoveUp
INC CURHALFTRK
@MoveHead
LDA CURHALFTRK ;compute phase number for new track
AND #$03
ASL
ORA #$60 ; slot number 6
TAY
LDA PHSON,Y ; turn on phase to move
LDA #$56
JSR F8ROM_MONWAIT ; delay for physical action
LDA PHSOFF, Y ; turn off phase
JMP MoveTrack ; and see if there's more work to do
;; RecalibrateTrack: make sure we're on track 0 by moving more tracks
;; (outward) than exist on the drive
RecalibrateTrack
LDA #$80 ; move more half-tracks than exist
STA CURHALFTRK
LDA #$00
STA DSTHALFTRK
JMP MoveTrack
;; EraseTrack: Write 0x3000 nybbles of 0xFF to the current track.
;; Assumes disk is running and up to speed, and on the destination
;; track already.
;; Tromps A, Y, and zero-page ZP_SCRATCH
;; FIXME: need to be sure EraseTrack does not span pages or the timing
;; will be broken
EraseTrack
LDA #$30 ; 0x3000 nybbles to write
STA NYBCOUNT
LDX #$60 ; Slot 6
LDA DISK_LATCHW,X
LDA DISK_MODER,X
BPL @NOTWP
JMP WriteProtected ; Disk is write protected, so bail
@NOTWP
LDA #$FF ; nybble data to write
STA DISK_MODEW,X
CMP DISK_LATCHR,X ;4
BIT ZP_SCRATCH ;+3=7
LDY #$00 ;+2=9
@LoopA
DEC ZP_SCRATCH ;+5=14
NOP ;+2=16
@LoopB ; (always 16 here)
DEC ZP_SCRATCH ;+5=21
CMP $FFFF ;+4=25
NOP ;+2=27
STA DISK_LATCHW,X ;+5=32
CMP DISK_LATCHR,X ;4
DEY ;+2=6
BNE @LoopA ;+3 (branch)=9 or +2=8
DEC NYBCOUNT ;8+5=13
BNE @LoopB ;+3(branch)=16 or +2=15
JSR @rts ; waste +12=27
DEC ZP_SCRATCH ;+5=32
LDA DISK_MODER,X
LDA DISK_LATCHR,X
@rts
RTS
;; WriteTrack: write <6656 ($1A00) nybbles to the current track.
;; Assumes drive is on and up to speed, and on the right track.
;; The data to write is at NYBDATA.
;; FIXME: need to be sure WriteTrack does not span pages or the timing
;; will be broken
WriteTrack
LDA #>NYBDATA ; set up ZP_STORPTR to the start of NYBDATA
STA ZP_STORPTR+1
LDA #<NYBDATA
STA ZP_STORPTR
;; Bytes must be sent to the controller precisely once every 32
;; clock cycles.
;;
;; Copy <$1A00 bytes from (ZP_STORPTR) to the disk drive. We don't
;; count the bytes - instead, there's a 00 sentinel at the end of
;; the track data. When we get that, we branch to @doneWriting.
LDX #$60 ; Slot 6
LDA DISK_LATCHW,X
LDA DISK_MODER,X
BPL @NOTWP
JMP WriteProtected ; Disk is write protected, so bail
@NOTWP
LDY #$00
LDA (ZP_STORPTR),Y
STA DISK_MODEW,X
;; Start of timing critical section: one byte every 32 cycles
CMP DISK_LATCHR,X ; Start of first write... 4
JSR @rts ; waste +12 cycles = 16
NOP ; +2 = 18
@loopA ;coming in to loopA, we're at 18
NOP ; +2 = 20
NOP ; +2 = 22
CMP $00 ; waste +3 cycles = 25
@loopB ;coming in to loopB, we're at 25
NOP ; +2 = 27
STA DISK_LATCHW,X ;+5 = 32
CMP DISK_LATCHR,X ; Start of new write... 4
INY ;+2=6
BEQ @nextPage ; +2 (no branch)=8/+3 (branch)=9
@LoadNext
LDA (ZP_STORPTR),Y ;8+5=13
BEQ @doneWriting ;+2=15 / +3=16
JMP @loopA ;+3=18
@nextPage
INC ZP_STORPTR+1 ;9+6=15
LDA (ZP_STORPTR),Y ;+5=20
BEQ @doneWriting2 ;+2=22 / +3=23
JMP @loopB ;+3=25
@doneWriting ;coming in to @doneWriting we're at 16
CMP $00 ; waste +3 = 19
NOP ; +2 = 21
NOP ; +2 = 23
@doneWriting2 ; on entry here we're at 23
NOP ; +2 = 25
NOP ; +2 = 27
NOP ; +2 = 29
CMP $00 ; waste +3 = 32
;; Need to hit exactly 32 cycles *before* this DISK_MODER read
LDA DISK_MODER,X
LDA DISK_LATCHR,X
@rts
RTS
;; MakeTrackData: precompute a full track of nybblized data for
;; track (A), and store it at NYBDATA ($2000).
MakeTrackData
STA TARGETTRK
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LDA #0
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STA TARGETSEC
LDA #16
STA SECCOUNT ; we want to write 16 sectors of nyb'd data
LDA #>NYBDATA
STA ZP_STORPTR+1 ; high address
LDA #<NYBDATA
STA ZP_STORPTR ; low address
@NextSector
JSR MakeSectorData ; will increment ZP_STORPTR by 388 as it goes
INC TARGETSEC
DEC SECCOUNT
BNE @NextSector
;; Stick a 00 at the end -- it's an illegal byte for writing to the
;; disk controller, so we'll use it as the sentinel for when we've
;; reached the end of the data to write
LDY #$01
LDA #$00
STA (ZP_STORPTR),Y
RTS
;; MakeSectorData: Create one sector of nybblized data for
;; track TARGETTRK, sector TARGETSEC and store it at
;; ZP_STORPTR (low) +1 (high)
;; Increments ZP_STORPTR as it goes
;; trashes Y/A
MakeSectorData
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LDA TARGETTRK
JSR F8ROM_AHEX
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LDA TARGETSEC
JSR F8ROM_AHEX
JSR Prtmsg
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ASC " : generate sector data"
.byte $00
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LDY #16 ; write 16 sync bytes
LDA #$FF
@LoopA
DEY
STA (ZP_STORPTR),Y
CPY #00
BNE @LoopA
;; add 20 to ZP_STORPTR
LDA #16
CLC
ADC ZP_STORPTR
STA ZP_STORPTR
BCC @SectorHeader
INC ZP_STORPTR+1
@SectorHeader
;; Emit the sector header
LDY #$00
LDA #$D5 ; 3 bytes of header prolog
STA (ZP_STORPTR),Y
INY
LDA #$AA
STA (ZP_STORPTR),Y
INY
LDA #$96
STA (ZP_STORPTR),Y
INY
LDA #$FF ; Volume number (255), 4-and-4 encoded
STA (ZP_STORPTR),Y
INY
STA (ZP_STORPTR),Y
INY
LDA TARGETTRK ; Track number, 4-and-4 encoded
JSR _Store44
LDA TARGETSEC ; Sector number, 4-and-4 encoded
JSR _Store44
LDA TARGETTRK ; compute checksum
EOR TARGETSEC
EOR #$FF ; (volume number)
JSR _Store44 ; Store it, 4-and-4 encoded
LDA #$DE ; Sector header epilog
STA (ZP_STORPTR),Y
INY
LDA #$AA
STA (ZP_STORPTR),Y
INY
LDA #$EB
STA (ZP_STORPTR),Y
INY
;; 3 gap bytes
LDA #$FF
STA (ZP_STORPTR),Y
INY
STA (ZP_STORPTR),Y
INY
STA (ZP_STORPTR),Y
INY
LDA #$D5 ; Data prolog
STA (ZP_STORPTR),Y
INY
LDA #$AA
STA (ZP_STORPTR),Y
INY
LDA #$AD
STA (ZP_STORPTR),Y
INY
;; Add 20 to ZP_STORPTR
LDA ZP_STORPTR
CLC
ADC #20
STA ZP_STORPTR
BCC @SectorDataTime
INC ZP_STORPTR+1
@SectorDataTime
LDY #00
;; Now for the fun bit - 343 bytes of data! Prep a 256 byte sector
;; and then translate it to 6-and-2 encoding (plus checksum),
;; and store it at ZP_STORPTR
;;
;; The test sector data is the value of (track + sector),
;; incrementing 256 times. Easy to generate...
LDA TARGETTRK
CLC
ADC TARGETSEC
@SectorLoop
STA (ZP_SECTP),Y
TAX
INX
TXA
INY
BNE @SectorLoop ; store 256 bytes
;; Convert and store as 6-and-2 with checksum
JSR Encode6and2
;; Encode6and2 added 0x157 to ZP_STORPTR, so we don't have to
;; data epilog
LDY #$00
LDA #$DE ; Data prolog
STA (ZP_STORPTR),Y
INY
LDA #$AA
STA (ZP_STORPTR),Y
INY
LDA #$EB
STA (ZP_STORPTR),Y
INY
;; add 3 bytes to ZP_STORPTR
LDA #$03
CLC
ADC ZP_STORPTR
BCC @finishnocarry
INC ZP_STORPTR+1
@finishnocarry
STA ZP_STORPTR
RTS
;; Store A in (ZP_STORPTR),Y with 4-and-4 encoding (2 bytes)
;; increments Y by 2, trashes A and ZP_SCRATCH
_Store44
STA ZP_SCRATCH
AND #$AA
LSR
ORA #$AA
STA (ZP_STORPTR),Y
INY
LDA ZP_SCRATCH
AND #$55
ORA #$AA
STA (ZP_STORPTR),Y
INY
RTS
;; Encode6and2: given 256 bytes of data at SECDATA, 6-and-2
;; encode it in to 0x156 nybble-bytes at (ZP_STORPTR) with a
;; 1-byte checksum after (== 0x157 total).
;; Trashes A and Y and X
;; Updates ZP_STORPTR
;; trashes ZP_STOR2, ZP_TRANSP, IDX6, IDX2, CKSUM,
;; ZP_SECTP
Encode6and2
LDA ZP_STORPTR ; set up ZP_STOR2 to point 256 bytes above
STA ZP_STOR2 ; ZP_STORPTR for convenience, since we're
LDY ZP_STORPTR+1 ; addressing an output buffer of > 0x100
INY ; bytes
STY ZP_STOR2+1
;; Clear output buffer 0x157 bytes
LDY #$00
LDA #$00
STA CKSUM ; convenient place to clear the checksum for later
@ClearLoop
STA (ZP_STORPTR),Y
CPY #$57 ; also clear at +0x100 if < 0x157
BLT @AlsoClearHigh ;Y < #$57? Branch
@ClearNext
INY
BEQ @ClearDone ; if Y became 0, we rolled over and are done
JMP @ClearLoop
@AlsoClearHigh
STA (ZP_STOR2),Y
JMP @ClearNext
@ClearDone
;; Work through the 256 bytes of data to construct the 6and2 data,
;; with ZP_SECTP as the input and ZP_STORPTR as the output
;;
LDA #$55
STA IDX2
;; for (idx6 = 0x0101; idx6 >= 0; idx6--)
LDA #$01
STA IDX6
STA IDX6+1 ; IDX6 = 0x0101
@WorkLoopA
LDY IDX6 ; val6 = input[idx6 & 0xFF]
LDA (ZP_SECTP),Y
STA VAL6
LDY IDX2 ; val2 = output[idx2];
LDA (ZP_STORPTR),Y
STA VAL2
;; val2 = (val2 << 1) | (val6 & 1); val6 >>= 1;
LSR VAL6+1
ROR VAL6 ; val6 >>= 1, and C = old (val6&1)
LDA VAL2
ROL ; A = (val2 << 1) | C
STA VAL2 ; val2 = all that jazz
;; another round of the same
LSR VAL6+1
ROR VAL6 ; val6 >>= 1, and C = old (val6&1)
LDA VAL2
ROL ; A = (val2 << 1) | C
STA VAL2 ; val2 = all that jazz
LDY IDX2 ; output[idx2] = val2
LDA VAL2
STA (ZP_STORPTR),Y
;; if (idx6 < 0x100) { output[0x56+idx6] = val6; }
LDA IDX6+1
CMP #01
BEQ @decidx2
LDA #$56
CLC
ADC IDX6
BCC @storeLT100
;; we need to store in ZP_STOR2 (the result overflowed)
TAY ; Y = idx6 + 0x56 and is >= 0x100
LDA VAL6
STA (ZP_STOR2),Y
JMP @decidx2
@storeLT100
TAY ; Y = idx6 + 0x56 and is < 0x100
LDA VAL6
STA (ZP_STORPTR),Y
JMP @decidx2
@decidx2
;; if (--idx2 < 0) { idx2 = 0x55; }
;; IDX2 never exceeds $55, so we can test using DEC and BMI/BPL
DEC IDX2
BPL @dontresetidx2
;; ... high bit is set, so we underflowed; reset IDX2 back to $55
LDA #$55
STA IDX2
@dontresetidx2
;; End of WorkLoopA: 16-bit decrement idx6, and loop to @WorkLoopA
;; if it is >= 0
LDA IDX6 ; sets Z if it's zero
BNE @simpledeclo ; if not zero, just decrement and continue
LDA IDX6+1 ; low was zero, so repeat w/ high
BEQ @DoneWorkloopA ; if high is also zero we're done
DEC IDX6+1
@simpledeclo
DEC IDX6
;; continue loop
JMP @WorkLoopA
;; Both IDX6 and IDX6+1 reached 0, so we are done the loop
@DoneWorkloopA
;; Mask out the "extra" 2-bit data:
;; output[0x54] &= 0x0F; output[0x55] &= 0x0F;
LDY #$54
LDA (ZP_STORPTR),Y
AND #$0F
STA (ZP_STORPTR),Y
INY
AND #$0F
STA (ZP_STORPTR),Y
;; Loop over the data one more time to construct the actual output
;; and compute the checksum
;; Checksum is initialized to 0 above
;; for (int idx6=0; idx6<0x156; idx6++)
LDA #$00
STA IDX6+1
STA IDX6
@WorkLoopB
LDY IDX6 ; val = output[idx]
LDA IDX6+1
EOR #$01
BEQ @LoadFromHi
LDA (ZP_STORPTR),Y
JMP @c
@LoadFromHi
LDA (ZP_STOR2),Y
@c
STA ZP_SCRATCH
;; output[idx] = _trans[cksum^val]
LDA CKSUM ; Y = cksum ^ val
EOR ZP_SCRATCH
TAY
LDA IDX6+1
EOR #$01 ; to set C for BEQ coming up
BEQ @StoreToHi ; branch based on EOR (if IDX6+1 == 1)
LDA (ZP_TRANSP),Y ; A = trans[cksum^val]
LDY IDX6 ; restore Y
STA (ZP_STORPTR),Y
JMP @d
@StoreToHi
LDA (ZP_TRANSP),Y ; A = trans[cksum^val]
LDY IDX6 ; restore Y
STA (ZP_STOR2),Y
@d
;; cksum = val;
LDA ZP_SCRATCH
STA CKSUM
;; Complete for loop: idx6++ and loop if idx6 < 0x156
INC IDX6
BEQ @incHigh
@f
LDA IDX6+1
EOR #$01
BNE @WorkLoopB ; high byte isn't set yet, so continue looping
LDA IDX6
CMP #$56
BGE @setCksum ; high byte set, and low >= 0x56 - done loop
JMP @WorkLoopB
@incHigh
INC IDX6+1
JMP @f
@setCksum
;; output[342] = _trans[cksum]
LDY CKSUM ; A = _trans[cksum]
LDA (ZP_TRANSP),Y
LDY #$56
STA (ZP_STOR2),Y ; output[0x100 + Y] = A
;; Add 0x157 to ZP_STORPTR (number of bytes we added to the buffer)
INC ZP_STORPTR+1 ; add 0x100
LDA ZP_STORPTR
CLC
ADC #$57
BCC @nocarry
INC ZP_STORPTR+1
@nocarry
STA ZP_STORPTR
@done
RTS
;; set CNT, CNT+1, DST, DST+1, VALUE before calling
memset
@a
LDY #0
LDA CNT
ORA CNT+1
BEQ @fin
LDA VALUE
STA (DST),y
INC DST
BNE @b
INC DST+1
@b
DEC CNT
LDA CNT
CMP #$FF
BNE @c
DEC CNT+1
@c
SEC
BCS @a
@fin
RTS
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;; Seccmp: compare SECDATA and DOS33_SECBUF (256 bytes)
;; return with carry clear if compare is ok; set if differences are
;; found
Seccmp
LDA #>SECDATA
STA ZP_STORPTR+1
LDA #<SECDATA
STA ZP_STORPTR
LDA #>DOS33_SECBUF
STA ZP_STOR2+1
LDA #<DOS33_SECBUF
STA ZP_STOR2
LDY #$FF
@next
/*
TYA ;debug message - save Y before & restore after
PHA
JSR F8ROM_AHEX ;byte number
LDA (ZP_STORPTR),Y
JSR F8ROM_AHEX
LDA (ZP_STOR2),Y
JSR F8ROM_AHEX
JSR Prtmsg
ASC " : byte cmp"
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.byte $00
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PLA
TAY
*/
LDA (ZP_STORPTR),Y
SEC
SBC (ZP_STOR2),Y
BNE @doneError
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TYA
BEQ @done ;if Y==0 we're done
DEY
JMP @next
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@done
CLC ;no error
RTS
@doneError
SEC ;error
RTS
WriteOneTrack
;; Fill track with as many FF bytes as we think fit. Per
;; https://retrocomputing.stackexchange.com/questions/503/absolute-maximum-number-of-nibbles-on-an-apple-ii-floppy-disk-track
;; track 0 can't reasonably fit more than about 8300 nybbles, so
;; we will write 8400 nybbles to be sure to have cleared any possible
;; track (track 0 is the physically largest, on the outside of
;; the disk; so track 35 will be multiply covered easily).
PHA ; save A on the way in
STA TARGETTRK
;; postion the head for the traget track
ASL ; multiply by 2
STA DSTHALFTRK
JSR MoveTrack
;; Fill the track with 0xFF sync bytes (ensuring we've wiped the track)
JSR EraseTrack
;; Write out a track of nybblized sectors to Track 0 for physical
;; sectors 0 through 15. The data in each is algorithmic, same as
;; the wozzle test disk pattern test #7 -- 256 incrementing bytes
;; starting at (sector + track).
;; Precompute one track of nybblized data at NYBDATA for the given track
LDA TARGETTRK
JSR MakeTrackData
;; Write it to the track
JSR WriteTrack
PLA ; restore A on the way out
RTS
;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Start of data segment
;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; variable space
;;
;; Many/all of these could be zero-page and not here.
;; They also don't need to be initialized to zero so they
;; could just be memory locations instead of byte defines.
;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
WAITCTR
.byte $00, $00
CURHALFTRK
.byte $00
DSTHALFTRK
.byte $00
NYBCOUNT
.byte $00
TARGETTRK
.byte $00
TARGETSEC
.byte $00
SECCOUNT
.byte $00
IDX6
.byte $00, $00
IDX2
.byte $00
CKSUM
.byte $00
VAL2
.byte $00
VAL6
.byte $00
CNT
.byte $00, $00
VALUE
.byte $00
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/*IOB
.tag iob_t*/
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;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; Block (read-only) data area
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;;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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DCT
.byte $00 ; decide type ($00 = DiskII)
.byte $01 ; phases per track ($01 for DiskII)
.byte $EF, $D8 ; motor on time count ($EFD8 for DiskII)
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.align 256
;; 6-and-2 DOS3.3 translation table (here so it doesn't
;; cross a page boundary)
TRANS62
.byte $96, $97, $9a, $9b, $9d, $9e, $9f, $a6
.byte $a7, $ab, $ac, $ad, $ae, $af, $b2, $b3
.byte $b4, $b5, $b6, $b7, $b9, $ba, $bb, $bc
.byte $bd, $be, $bf, $cb, $cd, $ce, $cf, $d3
.byte $d6, $d7, $d9, $da, $db, $dc, $dd, $de
.byte $df, $e5, $e6, $e7, $e9, $ea, $eb, $ec
.byte $ed, $ee, $ef, $f2, $f3, $f4, $f5, $f6
.byte $f7, $f9, $fa, $fb, $fc, $fd, $fe, $ff
;; scratch space for a sector of data
;; FIXME: is there an easier way to define a block so that
;; ca65 honors it and shows it properly in the lst?
.align 256
SECDATA
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
.byte $00, $00, $00, $00, $00, $00, $00, $00
;; nybblized data that we precalculate
;; and then write to the track; or that we read in from the track
;; and store here
.align 256
NYBDATA
.byte $00
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