init: move.w $dff01c,oldintena
move.w $dff01e,oldintreq
bset #7,oldintena
bset #7,oldintreq
move.w #$7fff,$dff09a ; interrupts aus.
move.w #$7fff,$dff09c ;

;****************************************************************

lea $dff000,a6
lea buffer(pc),a0
lea mfmbuffer,a2
move.l #5*$1600,d0
move.l #0,d1
move.l #$0,d2
jsr trackloader

;****************************************************************

move.w oldintena(pc),$dff09a
move.w oldintreq(pc),$dff09c
moveq #0,d0
rts

oldintena: dc.w 0
oldintreq: dc.w 0
buffer: blk.b 130000,0
mfmbuffer: blk.w 6400,0

; ============================================================================

; HARDWARE-DISKLOADER (c) ALPHA ONE 2005.
; ***************************************
; IMPROVED TO READ FROM ODD BYTEPOSITIONS.
; PRO VERSION -> WITH TRACKCOUNTER.
; IN: A6=$DFF000
; A2=MFMBUFFER.L
; A0=BUFFER.L
; D0=LENGTH.L
; D1=TRACKNR.L
; D2=BYTEOFFSET.L

TRACKLOADER:

LEA $BFD100,A4 ; DRIVESELECT REGISTER
LEA $BFE001,A5 ; DRIVESTATUS REGISTER
LEA CURRENTTRACK(PC),A3 ; HOLDS THE ACTUAL TRACKPOS
MOVEQ #0,D7 ; D7 = BYTECOUNTER
ADD.L D2,D0 ; BYTES TO READ + BYTEOFFSET
MOVE.L D0,D3
DIVS.W #$1600,D3
MOVE.B D3,1(A3)

MOVE.B #$7D,(A4) ; SWITCH MOTOR DRIVE 0 ON
NOP ; =======================
NOP
MOVE.B #$75,(A4)
BSR.W DELAY
BSR.W DISKREADY

CMP.B #$FF,(A3)
BNE.B MOVETOCYLINDER
MOVE.B #0,(A3)
BSET #1,(A4) ; CHOSE DIRECTION TOWARDS 0
MOVETOZERO: BTST #4,(A5) ; HEAD ON CYLINDER 0?
BEQ.B MOVETOCYLINDER
BSR.W MOVEHEAD ; MOVE HEAD + DELAY
BRA.B MOVETOZERO

MOVETOCYLINDER: BSET #2,(A4) ; CHOOSE HEAD HIGH
BTST #0,D1 ; EVEN OR ODD TRACK?
BEQ.B HEADOK ; TRACK IS EVEN – ALRIGHT!
BCLR #2,(A4) ; CHOOSE HEAD LOW
HEADOK: MOVEQ #0,D3
MOVEQ #0,D5
MOVE.B D1,D3 ; NEW TRACKNUM -> D3
MOVE.B (A3),D5 ; CURRENT TRACK -> D5
MOVE.B D1,(A3) ; REPLACE CURRENT TRACK
LSR.W #1,D3 ; GET CYLINDER NUM NEW TRACK
LSR.W #1,D5 ; GET CYLINDER NUM CUR TRACK
SUB.W D3,D5
BEQ.B READTRACK
BMI.B OTHERDIRECTION
BSET #1,(A4) ; CHOOSE DIRECTION TOWARDS 0
BRA.B CHOSEN
OTHERDIRECTION: BCLR #1,(A4) ; CHOOSE DIRECTION OUTWARDS 0
NEG.W D5
CHOSEN: BSR.W MOVEHEAD
SUBQ.B #1,D5
BNE.B CHOSEN

READTRACK: BSR.W DISKREADY ; EINEN TRACK LESEN
MOVE.W #$8210,$96(A6) ; =================
MOVE.W #$7F00,$9E(A6)
MOVE.W #$8500,$9E(A6)
MOVE.W #$4489,$7E(A6)
MOVE.W #$4000,$24(A6)
MOVE.L A2,$20(A6)
MOVE.W #$9900,$24(A6)
MOVE.W #$9900,$24(A6)
MOVE.W #$2,$9C(A6)
TRACKREADY: BTST #1,$DFF01F
BEQ.B TRACKREADY
MOVE.W #$4000,$24(A6)

MOVEQ #0,D5 ; DECODE TRACK
DECODE: MOVE.L A2,A1 ; ============
MOVE.L #$55555555,D4
FINDSYNC: CMP.W #$4489,(A1)+
BNE.B FINDSYNC
CMP.W #$4489,(A1)
BEQ.B FINDSYNC
MOVE.L (A1),D3
MOVE.L 4(A1),D1
AND.L D4,D3
AND.L D4,D1
ASL.L #1,D3
OR.L D1,D3
ROR.L #8,D3
CMP.B D5,D3
BEQ.B SECTORFOUND
ADD.L #1086,A1
BRA.B FINDSYNC
SECTORFOUND: ADD.L #56,A1
MOVE.L #(512/4)-1,D6
DECODESECTOR: MOVE.L 512(A1),D1
MOVE.L (A1)+,D3
AND.L D4,D3
AND.L D4,D1
ASL.L #1,D3
OR.L D1,D3
LEA STORE(PC),A3
MOVE.L D3,(A3)

MOVEQ #4-1,D3
LOOP: CMP.L D7,D0
BEQ.B READREADY
CMP.L D7,D2
BGT.B BELOW
MOVE.B (A3),(A0)+
BELOW: ADDQ.L #1,A3
ADDQ.L #1,D7
DBF D3,LOOP

DBF D6,DECODESECTOR
ADDQ.B #1,D5
CMP.B #11,D5
BNE.B DECODE

TRACKDONE: CMP.L D7,D0 ; TRACK DONE, GET ONTO NEXT.
BEQ.B READREADY ; ==========================
BTST #2,(A4)
BEQ.B ONTONEXT
BCLR #2,(A4)
BSR.W DELAY
BRA.W READTRACK
ONTONEXT: BSET #2,(A4)
BSR.W DELAY
BCLR #1,(A4)
BSR.W MOVEHEAD
BRA.W READTRACK

READREADY: MOVE.B #$FD,(A4) ; SWITCH MOTOR DRIVE 0 OFF
NOP ; ========================
NOP
MOVE.B #$E7,(A4)
LEA CURRENTTRACK(PC),A3
MOVE.B 1(A3),D0
ADD.B D0,(A3)
RTS

DELAY: CLR.B $300(A4) ; DELAY ROUTINE
MOVE.B #$19,$400(A4) ; =============
MOVE.B #$1,$D00(A4)
WAIT: BTST #0,$C00(A4)
BEQ.B WAIT
BCLR #0,$D00(A4)
RTS

DISKREADY: BTST #5,(A5) ; WAIT FOR DISK-READY
BNE.B DISKREADY ; ===================
RTS

MOVEHEAD: BCLR #0,(A4)
BSR.W DELAY
BSET #0,(A4)
BSR.W DELAY
RTS

CURRENTTRACK: DC.B $FF,0
STORE: DC.L 0

TRACKLOADERENDE:

; ============================================================================

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offline 21 hours

mus@shi9

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Comments: 1160Publics: 2778Registration: 06-03-2017

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scenex
8 years ago

Alpha One, I’ve extended your trackloader to support multiple drives.
Would you mind it being published here on Flashtro? 🙂

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aLpHa oNe
Reply to  scenex
8 years ago

No problem although the original is a bit buggy I suppose. 😉

0
scenex
Reply to  aLpHa oNe
8 years ago

I’ve used it in 2 cracks and so far it worked 🙂 The only “bug” i could observe is that the drive motors were not turned off after track loading. I changed the program flow a bit, where is waits for 500ms before checking the DSKRDY flag and turns off the motor and quits in case the check failed.

0
aLpHa oNe
Reply to  scenex
8 years ago

Ok, nice to hear. :p

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aLpHa oNe
13 years ago

kaggaichchecknix352352354.s 😉

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SIRIaX
SIRIaX
13 years ago

was? achso!

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