DiskII formatter: add reference material for ProDOS formatter routine (#125)
This commit is contained in:
tomcw
parent
b50da5a95b
commit
7b6be0827d
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@ -0,0 +1,806 @@
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;*
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;*
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;* * * * * * * * * * * * * * * * * * * * * * * * * * * *
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;* * * * * * * * * * * * * * * * * * * * * * * * * * * *
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;* * * *
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;* * M U S T B E O N P A G E B O U N D A R Y * *
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;* * * *
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;* * * * * * * * * * * * * * * * * * * * * * * * * * * *
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;* * * * * * * * * * * * * * * * * * * * * * * * * * * *
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;* *
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;* ProDOS DISK ][ Formatter Device Driver *
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;* *
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;* Copyright Apple Computer, Inc., 1982-1984 *
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;* *
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;* Enter with ProDOS device number in A-register: *
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;* Zero = bits 0, 1, 2, 3 *
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;* Slot No.= bits 4, 5, 6 *
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;* Drive 1 = bit 7 off *
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;* Drive 2 = bit 7 on *
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;* *
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;* Error codes returned in A-register: *
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;* $00 : Good completion *
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;* $27 : Unable to format *
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;* $2B : Write-Protected *
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;* $33 : Drive too SLOW *
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;* $34 : Drive too FAST *
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;* NOTE: Carry flag is set if error occured. *
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;* *
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;* Uses zero page locations $D0 thru $DD *
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;* *
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;* - - - - - - - - - - - - - - - - - - - - - - - - - - *
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;* Modified 15 December 1983 to disable interrupts *
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;* Modified 20 December 1983 to increase tolerance *
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;* of disk speed check *
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;* Modified 30 March 1983 to increase tolerance of *
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;* disk speed *
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;* * * * * * * * * * * * * * * * * * * * * * * * * * * *
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;
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; Disassembly and annotations by TC (Nov. 2017)
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; . disassembly from prodos_utility.dsk (ProDOS 1.1.1)
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;
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;
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; Entrypoint
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; Pre: A=slot*16, ($DE)=#$01=volume#
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;
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7900- 08 PHP
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7901- 78 SEI ; interrupt disable
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7902- 20 3A 79 JSR $793A
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7905- 28 PLP ; restore interrupt ena/dis state
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7906- C9 00 CMP #$00
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7908- D0 02 BNE $790C
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790A- 18 CLC ; res=OK
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790B- 60 RTS
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; error:
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790C- C9 02 CMP #$02
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790E- D0 05 BNE $7915
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7910- A9 2B LDA #$2B ; MLI error: write protected
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7912- 4C 21 79 JMP $7921
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;
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7915- C9 01 CMP #$01
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7917- D0 05 BNE $791E
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7919- A9 27 LDA #$27 ; MLI error: I/O error
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791B- 4C 21 79 JMP $7921
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;
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791E- 18 CLC
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791F- 69 30 ADC #$30 ; =>$33 or $34
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7921- 38 SEC ; res=ERROR
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7922- 60 RTS
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; end
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; Seek to track
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; Pre: A=trk#, X=slot*16
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7923- 0A ASL ; A=half track
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7924- 0E 24 7D ASL $7D24
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7927- 8D 36 7D STA $7D36
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792A- 8A TXA
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792B- 4A LSR
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792C- 4A LSR
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792D- 4A LSR
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792E- 4A LSR ; A=slot
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792F- A8 TAY ; Y=slot
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7930- AD 36 7D LDA $7D36
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7933- 20 C6 7A JSR $7AC6
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7936- 4E 24 7D LSR $7D24
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7939- 60 RTS
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; ??? (end)
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; FormatDisk (called from Entrypoint)
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; Pre: A=slot*16, A.b7=drive#
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793A- AA TAX
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793B- 29 70 AND #$70
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793D- 8D 23 7D STA $7D23 ; set slot*16
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7940- 8A TXA
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7941- AE 23 7D LDX $7D23
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7944- 2A ROL ; C=drive#
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7945- A9 00 LDA #$00
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7947- 2A ROL
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7948- D0 06 BNE $7950
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794A- BD 8A C0 LDA $C08A,X ; select drive-1
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794D- 4C 53 79 JMP $7953
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7950- BD 8B C0 LDA $C08B,X ; select drive-2
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;
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7953- BD 89 C0 LDA $C089,X ; motor on
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7956- A9 D7 LDA #$D7
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7958- 85 DA STA $DA ; ($DA) = #$D7
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795A- A9 50 LDA #$50
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795C- 8D 24 7D STA $7D24 ; ($7D24) = 80
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; Seek to track 0
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795F- A9 00 LDA #$00
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7961- 20 23 79 JSR $7923
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; Wait (until motor up to speed?)
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7964- A5 DA LDA $DA ; read_vol
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7966- F0 06 BEQ $796E
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7968- 20 3A 7C JSR $7C3A ; Wait incs read_vol
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796B- 4C 64 79 JMP $7964
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; Init vars/consts
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796E- A5 DE LDA $DE
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7970- 85 D3 STA $D3 ; ($D3) = write_vol = 1 (constant)
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7972- A9 AA LDA #$AA
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7974- 85 D0 STA $D0 ; ($D0) = #$AA (constant)
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7976- AD 20 7D LDA $7D20 ; max_gap3
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7979- 18 CLC
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797A- 69 02 ADC #$02
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797C- 85 D4 STA $D4 ; ($D4) = max_gap3 + 2
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797E- A9 00 LDA #$00
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7980- 85 D1 STA $D1 ; ($D1) = write_trk = 0
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; Write next track
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7982- A5 D1 LDA $D1
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7984- AE 23 7D LDX $7D23
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7987- 20 23 79 JSR $7923
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798A- AE 23 7D LDX $7D23
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798D- BD 8D C0 LDA $C08D,X ; load disk write prot to latch(b7=1 => write protected)
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7990- BD 8E C0 LDA $C08E,X ; set read mode & read latch
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7993- A8 TAY
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7994- BD 8E C0 LDA $C08E,X ; set read mode
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7997- BD 8C C0 LDA $C08C,X ; read nib to latch & read latch
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799A- 98 TYA
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799B- 10 05 BPL $79A2
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799D- A9 02 LDA #$02 ; Error = write protected
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799F- 4C F9 79 JMP $79F9
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; Write track
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79A2- 20 63 7C JSR $7C63
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79A5- 90 0E BCC $79B5
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; Error...
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79A7- A9 01 LDA #$01
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79A9- A4 D4 LDY $D4
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79AB- CC 1F 7D CPY $7D1F
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79AE- B0 02 BCS $79B2
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79B0- A9 04 LDA #$04
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79B2- 4C F9 79 JMP $79F9 ; error code = 4 (Drive too FAST)
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; Succeeded writing track, now check gap3_count tolerance
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79B5- A4 D4 LDY $D4
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79B7- CC 1F 7D CPY $7D1F
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79BA- B0 05 BCS $79C1
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79BC- A9 04 LDA #$04
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79BE- 4C F9 79 JMP $79F9 ; error code = 4 (Drive too FAST)
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;
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79C1- CC 20 7D CPY $7D20
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79C4- 90 05 BCC $79CB
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79C6- A9 03 LDA #$03
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79C8- 4C F9 79 JMP $79F9 ; error code = 3 (Drive too SLOW)
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; Read a max of 15 (not 16) address fields, looking for sector 0
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79CB- AD 22 7D LDA $7D22 ; A = #$10 (constant)
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79CE- 8D 25 7D STA $7D25
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;
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79D1- CE 25 7D DEC $7D25
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79D4- D0 05 BNE $79DB
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79D6- A9 01 LDA #$01
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79D8- 4C F9 79 JMP $79F9 ; error code = 1 (I/O error)
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79DB- AE 23 7D LDX $7D23
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79DE- 20 6A 7A JSR $7A6A ; Read address field
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79E1- B0 EE BCS $79D1
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79E3- A5 D8 LDA $D8 ; sector 0?
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79E5- D0 EA BNE $79D1 ; ... no, so keep reading
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; Got address field for sector 0:
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; Verify sector
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79E7- AE 23 7D LDX $7D23
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79EA- 20 07 7A JSR $7A07 ; ???
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79ED- B0 E2 BCS $79D1
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; Prep for formatting next track
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79EF- E6 D1 INC $D1 ; inc write_trk
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79F1- A5 D1 LDA $D1
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79F3- C9 23 CMP #$23 ; done 35 tracks?
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79F5- 90 8B BCC $7982 ; ... no, so write next track
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79F7- A9 00 LDA #$00 ; res = OK
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79F9- 48 PHA ; push error code
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79FA- AE 23 7D LDX $7D23
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79FD- BD 88 C0 LDA $C088,X
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7A00- A9 00 LDA #$00
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7A02- 20 23 79 JSR $7923
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7A05- 68 PLA ; pop error code
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7A06- 60 RTS
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; end
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;
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; Verify sector
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;
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; Read data prologue (D5 AA AD) within 32 nibbles
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7A07- A0 20 LDY #$20
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7A09- 88 DEY
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7A0A- F0 5C BEQ $7A68
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7A0C- BD 8C C0 LDA $C08C,X
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7A0F- 10 FB BPL $7A0C
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7A11- 49 D5 EOR #$D5
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7A13- D0 F4 BNE $7A09
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7A15- EA NOP
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7A16- BD 8C C0 LDA $C08C,X
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7A19- 10 FB BPL $7A16
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7A1B- C9 AA CMP #$AA
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7A1D- D0 F2 BNE $7A11
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7A1F- A0 56 LDY #$56 ; Y=#$56
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7A21- BD 8C C0 LDA $C08C,X
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7A24- 10 FB BPL $7A21
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7A26- C9 AD CMP #$AD
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7A28- D0 E7 BNE $7A11
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; Read data
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7A2A- A9 00 LDA #$00 ; ($D5) = #$FF = Number of #$96 nibbles to read
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7A2C- 88 DEY
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7A2D- 84 D5 STY $D5
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7A2F- BD 8C C0 LDA $C08C,X
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7A32- 10 FB BPL $7A2F
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7A34- C9 96 CMP #$96
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7A36- D0 30 BNE $7A68
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7A38- A4 D5 LDY $D5
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7A3A- D0 F0 BNE $7A2C
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;
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7A3C- 84 D5 STY $D5
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7A3E- BD 8C C0 LDA $C08C,X
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7A41- 10 FB BPL $7A3E
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7A43- C9 96 CMP #$96
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7A45- D0 21 BNE $7A68
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7A47- A4 D5 LDY $D5
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7A49- C8 INY
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7A4A- D0 F0 BNE $7A3C
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;
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7A4C- BD 8C C0 LDA $C08C,X
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7A4F- 10 FB BPL $7A4C
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7A51- C9 96 CMP #$96
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7A53- D0 13 BNE $7A68
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; Read data epilogue (DE AA)
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7A55- BD 8C C0 LDA $C08C,X
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7A58- 10 FB BPL $7A55
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7A5A- C9 DE CMP #$DE
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7A5C- D0 0A BNE $7A68 ; error
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7A5E- EA NOP
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7A5F- BD 8C C0 LDA $C08C,X
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7A62- 10 FB BPL $7A5F
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7A64- C9 AA CMP #$AA
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7A66- F0 5C BEQ $7AC4 ; CLC & RTS
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7A68- 38 SEC ; error
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7A69- 60 RTS
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; end
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;
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; Read address field
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;
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; Post:
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; ($D7) = Chksum
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; ($D8) = Sec
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; ($D9) = Trk
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; ($DA) = Vol
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;
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; Carry set => error:
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; . max nibble count read before addr prologue
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; . chksum error
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; . addr epilogue not correct
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;
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; Init: nibble count until error: 3+3*256 = 3+768 = 771
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7A6A- A0 FC LDY #$FC
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7A6C- 84 DC STY $DC
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; Read until address prologue (D5 AA 96)
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7A6E- C8 INY
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7A6F- D0 04 BNE $7A75
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7A71- E6 DC INC $DC
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7A73- F0 F3 BEQ $7A68 ; error
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7A75- BD 8C C0 LDA $C08C,X
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7A78- 10 FB BPL $7A75
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7A7A- C9 D5 CMP #$D5
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7A7C- D0 F0 BNE $7A6E
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7A7E- EA NOP
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7A7F- BD 8C C0 LDA $C08C,X
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7A82- 10 FB BPL $7A7F
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7A84- C9 AA CMP #$AA
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7A86- D0 F2 BNE $7A7A
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7A88- A0 03 LDY #$03 ; Y=3
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7A8A- BD 8C C0 LDA $C08C,X
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7A8D- 10 FB BPL $7A8A
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7A8F- C9 96 CMP #$96
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7A91- D0 E7 BNE $7A7A
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; Read 4&4
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; ($D7) = Chksum
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; ($D8) = Sec
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; ($D9) = Trk
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; ($DA) = Vol
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7A93- A9 00 LDA #$00
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7A95- 85 DB STA $DB ; update chksum
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7A97- BD 8C C0 LDA $C08C,X
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7A9A- 10 FB BPL $7A97
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7A9C- 2A ROL
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7A9D- 85 DD STA $DD
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7A9F- BD 8C C0 LDA $C08C,X
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7AA2- 10 FB BPL $7A9F
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7AA4- 25 DD AND $DD
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7AA6- 99 D7 00 STA $00D7,Y
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7AA9- 45 DB EOR $DB
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7AAB- 88 DEY
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7AAC- 10 E7 BPL $7A95
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;
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7AAE- A8 TAY
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7AAF- D0 B7 BNE $7A68 ; chksum error
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; Read epilogue (DE AA)
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7AB1- BD 8C C0 LDA $C08C,X
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7AB4- 10 FB BPL $7AB1
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7AB6- C9 DE CMP #$DE
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7AB8- D0 AE BNE $7A68 ; error
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7ABA- EA NOP
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7ABB- BD 8C C0 LDA $C08C,X
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7ABE- 10 FB BPL $7ABB
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7AC0- C9 AA CMP #$AA
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7AC2- D0 A4 BNE $7A68 ; error
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7AC4- 18 CLC ; res = OK
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7AC5- 60 RTS
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; end
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; Seek to half track
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; Pre: A=half track#, X=slot*16, Y=slot
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7AC6- 8E 37 7D STX $7D37
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7AC9- 8D 36 7D STA $7D36
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7ACC- CD 24 7D CMP $7D24
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7ACF- F0 5C BEQ $7B2D
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7AD1- A9 00 LDA #$00
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7AD3- 8D 38 7D STA $7D38
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7AD6- AD 24 7D LDA $7D24
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7AD9- 8D 39 7D STA $7D39
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7ADC- 38 SEC
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7ADD- ED 36 7D SBC $7D36
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7AE0- F0 37 BEQ $7B19
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7AE2- B0 07 BCS $7AEB
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7AE4- 49 FF EOR #$FF
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7AE6- EE 24 7D INC $7D24
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7AE9- 90 05 BCC $7AF0
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7AEB- 69 FE ADC #$FE
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7AED- CE 24 7D DEC $7D24
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7AF0- CD 38 7D CMP $7D38
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7AF3- 90 03 BCC $7AF8
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7AF5- AD 38 7D LDA $7D38
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7AF8- C9 0C CMP #$0C
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7AFA- B0 01 BCS $7AFD
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7AFC- A8 TAY
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7AFD- 38 SEC
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7AFE- 20 1D 7B JSR $7B1D
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7B01- B9 4B 7C LDA $7C4B,Y
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7B04- 20 3A 7C JSR $7C3A
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7B07- AD 39 7D LDA $7D39
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7B0A- 18 CLC
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7B0B- 20 20 7B JSR $7B20
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7B0E- B9 57 7C LDA $7C57,Y
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7B11- 20 3A 7C JSR $7C3A
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7B14- EE 38 7D INC $7D38
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7B17- D0 BD BNE $7AD6
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7B19- 20 3A 7C JSR $7C3A
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7B1C- 18 CLC
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7B1D- AD 24 7D LDA $7D24
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7B20- 29 03 AND #$03
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7B22- 2A ROL
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7B23- 0D 37 7D ORA $7D37
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7B26- AA TAX
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7B27- BD 80 C0 LDA $C080,X
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7B2A- AE 37 7D LDX $7D37
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7B2D- 60 RTS
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; end
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;
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; Write gap2, Data field, data
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;
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7B2E- 20 0E 7D JSR $7D0E
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7B31- BD 8D C0 LDA $C08D,X
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7B34- BD 8E C0 LDA $C08E,X
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; Write gap2 (5x 10-bit FF)
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7B37- A9 FF LDA #$FF
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7B39- 9D 8F C0 STA $C08F,X
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7B3C- DD 8C C0 CMP $C08C,X
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7B3F- 48 PHA
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7B40- 68 PLA
|
||||
7B41- EA NOP
|
||||
7B42- A0 04 LDY #$04
|
||||
7B44- 48 PHA
|
||||
7B45- 68 PLA
|
||||
7B46- 20 A5 7B JSR $7BA5
|
||||
7B49- 88 DEY
|
||||
7B4A- D0 F8 BNE $7B44
|
||||
|
||||
; Write Data prologue (D5 AA AD)
|
||||
7B4C- A9 D5 LDA #$D5
|
||||
7B4E- 20 A4 7B JSR $7BA4
|
||||
7B51- A9 AA LDA #$AA
|
||||
7B53- 20 A4 7B JSR $7BA4
|
||||
7B56- A9 AD LDA #$AD
|
||||
7B58- 20 A4 7B JSR $7BA4
|
||||
|
||||
; Write 86 x #$96
|
||||
7B5B- A0 56 LDY #$56
|
||||
7B5D- EA NOP
|
||||
7B5E- EA NOP
|
||||
7B5F- EA NOP
|
||||
7B60- D0 03 BNE $7B65
|
||||
7B62- 20 0E 7D JSR $7D0E ; RTS
|
||||
7B65- EA NOP
|
||||
7B66- EA NOP
|
||||
7B67- A9 96 LDA #$96
|
||||
7B69- 9D 8D C0 STA $C08D,X
|
||||
7B6C- DD 8C C0 CMP $C08C,X
|
||||
7B6F- 88 DEY
|
||||
7B70- D0 F0 BNE $7B62
|
||||
|
||||
; Write 256 x #$96
|
||||
7B72- 24 00 BIT $00
|
||||
7B74- EA NOP
|
||||
7B75- 20 0E 7D JSR $7D0E ; RTS
|
||||
7B78- A9 96 LDA #$96
|
||||
7B7A- 9D 8D C0 STA $C08D,X
|
||||
7B7D- DD 8C C0 CMP $C08C,X
|
||||
7B80- A9 96 LDA #$96
|
||||
7B82- EA NOP
|
||||
7B83- C8 INY
|
||||
7B84- D0 EF BNE $7B75
|
||||
|
||||
; Write Data epilogue (DE AA EB FF)
|
||||
7B86- 20 A4 7B JSR $7BA4
|
||||
7B89- A9 DE LDA #$DE
|
||||
7B8B- 20 A4 7B JSR $7BA4
|
||||
7B8E- A9 AA LDA #$AA
|
||||
7B90- 20 A4 7B JSR $7BA4
|
||||
7B93- A9 EB LDA #$EB
|
||||
7B95- 20 A4 7B JSR $7BA4
|
||||
7B98- A9 FF LDA #$FF
|
||||
7B9A- 20 A4 7B JSR $7BA4
|
||||
;
|
||||
7B9D- BD 8E C0 LDA $C08E,X ; read latch (and set read mode)
|
||||
7BA0- BD 8C C0 LDA $C08C,X ; read latch
|
||||
7BA3- 60 RTS
|
||||
|
||||
; Write nibble
|
||||
7BA4- EA NOP
|
||||
; Write nibble
|
||||
7BA5- 48 PHA
|
||||
7BA6- 68 PLA
|
||||
7BA7- 9D 8D C0 STA $C08D,X
|
||||
7BAA- DD 8C C0 CMP $C08C,X
|
||||
7BAD- 60 RTS
|
||||
|
||||
;
|
||||
; Write gap1(sector-0) or gap3 & address field
|
||||
; Pre: X=slot*16, Y=gap count
|
||||
;
|
||||
|
||||
; Check if disk is write enabled
|
||||
7BAE- 38 SEC ; ? (2 cycles)
|
||||
7BAF- BD 8D C0 LDA $C08D,X ; load write protect to latch (b7)
|
||||
7BB2- BD 8E C0 LDA $C08E,X ; read latch (and set read mode)
|
||||
7BB5- 30 5E BMI $7C15 ; branch if write protected
|
||||
|
||||
; Gap1 or Gap3: Initial 10-bit FF sync byte
|
||||
7BB7- A9 FF LDA #$FF
|
||||
7BB9- 9D 8F C0 STA $C08F,X ; set write mode & write data to latch
|
||||
7BBC- DD 8C C0 CMP $C08C,X ; start writing latch (start shifting)
|
||||
7BBF- 48 PHA
|
||||
7BC0- 68 PLA
|
||||
|
||||
; Gap1 or Gap3: 10-bit FF sync byte (40 cycle loop)
|
||||
; Pre: A=#$FF, Y=gap count
|
||||
7BC1- 20 1B 7C JSR $7C1B ; RTS
|
||||
7BC4- 20 1B 7C JSR $7C1B ; RTS
|
||||
7BC7- 9D 8D C0 STA $C08D,X ; write data to latch
|
||||
7BCA- DD 8C C0 CMP $C08C,X ; start writing latch (start shifting)
|
||||
7BCD- EA NOP
|
||||
7BCE- 88 DEY
|
||||
7BCF- D0 F0 BNE $7BC1 ; NB. branch taken cross pages
|
||||
|
||||
; Write address prologue (D5 AA 96)
|
||||
7BD1- A9 D5 LDA #$D5
|
||||
7BD3- 20 2D 7C JSR $7C2D
|
||||
7BD6- A9 AA LDA #$AA
|
||||
7BD8- 20 2D 7C JSR $7C2D
|
||||
7BDB- A9 96 LDA #$96
|
||||
7BDD- 20 2D 7C JSR $7C2D
|
||||
|
||||
; Write address field
|
||||
7BE0- A5 D3 LDA $D3 ; Vol=01
|
||||
7BE2- 20 1C 7C JSR $7C1C
|
||||
7BE5- A5 D1 LDA $D1 ; Trk
|
||||
7BE7- 20 1C 7C JSR $7C1C
|
||||
7BEA- A5 D2 LDA $D2 ; Sec
|
||||
7BEC- 20 1C 7C JSR $7C1C
|
||||
7BEF- A5 D3 LDA $D3
|
||||
7BF1- 45 D1 EOR $D1
|
||||
7BF3- 45 D2 EOR $D2
|
||||
7BF5- 48 PHA ; Chksum
|
||||
7BF6- 4A LSR
|
||||
7BF7- 05 D0 ORA $D0 ; OR with #$AA
|
||||
; write 4&4 chksum in A
|
||||
7BF9- 9D 8D C0 STA $C08D,X
|
||||
7BFC- BD 8C C0 LDA $C08C,X
|
||||
7BFF- 68 PLA
|
||||
7C00- 09 AA ORA #$AA
|
||||
7C02- 20 2C 7C JSR $7C2C
|
||||
|
||||
; write address epilogue (DE AA EB)
|
||||
7C05- A9 DE LDA #$DE
|
||||
7C07- 20 2D 7C JSR $7C2D
|
||||
7C0A- A9 AA LDA #$AA
|
||||
7C0C- 20 2D 7C JSR $7C2D
|
||||
7C0F- A9 EB LDA #$EB
|
||||
7C11- 20 2D 7C JSR $7C2D
|
||||
7C14- 18 CLC
|
||||
7C15- BD 8E C0 LDA $C08E,X
|
||||
7C18- BD 8C C0 LDA $C08C,X
|
||||
7C1B- 60 RTS
|
||||
|
||||
; write 4&4 byte in A
|
||||
7C1C- 48 PHA
|
||||
7C1D- 4A LSR
|
||||
7C1E- 05 D0 ORA $D0
|
||||
7C20- 9D 8D C0 STA $C08D,X
|
||||
7C23- DD 8C C0 CMP $C08C,X
|
||||
7C26- 68 PLA
|
||||
7C27- EA NOP
|
||||
7C28- EA NOP
|
||||
7C29- EA NOP
|
||||
7C2A- 09 AA ORA #$AA
|
||||
7C2C- EA NOP
|
||||
; fall through...
|
||||
|
||||
; 32 cycle write
|
||||
7C2D- EA NOP
|
||||
7C2E- 48 PHA
|
||||
7C2F- 68 PLA
|
||||
7C30- 9D 8D C0 STA $C08D,X
|
||||
7C33- DD 8C C0 CMP $C08C,X
|
||||
7C36- 60 RTS
|
||||
; end
|
||||
|
||||
; ??? (unused)
|
||||
7C37- C8 INY
|
||||
7C38- A0 C3 LDY #$C3
|
||||
; ??? (end)
|
||||
|
||||
; Wait: A * (2 + (5*16) + 5+3+5+2+2+3) = A * 102 cycles (roughly)
|
||||
; Pre: A = wait value
|
||||
7C3A- A2 11 LDX #$11 ; 2cy
|
||||
7C3C- CA DEX ; 2cy
|
||||
7C3D- D0 FD BNE $7C3C ; 2+1 (branch taken)
|
||||
7C3F- E6 D9 INC $D9 ; 5cy / read_trk++
|
||||
7C41- D0 02 BNE $7C45 ; 2+1 (branch taken)
|
||||
7C43- E6 DA INC $DA ; 5cy / read_vol++
|
||||
7C45- 38 SEC ; 2cy
|
||||
7C46- E9 01 SBC #$01 ; 2cy
|
||||
7C48- D0 F0 BNE $7C3A ; 2+1 (branch taken)
|
||||
7C4A- 60 RTS
|
||||
; end
|
||||
|
||||
.data
|
||||
7C4B: ; 12 bytes
|
||||
!byte $01,$30,$28
|
||||
!byte $24,$20,$1E
|
||||
!byte $1D,$1C,$1C
|
||||
!byte $1C,$1C,$1C
|
||||
7C57: ; 12 bytes
|
||||
!byte $70,$2C,$26
|
||||
!byte $22,$1F,$1E
|
||||
!byte $1D,$1C,$1C
|
||||
!byte $1C,$1C,$1C
|
||||
|
||||
.code
|
||||
|
||||
;
|
||||
; Write track and verify track
|
||||
;
|
||||
|
||||
; write gap1 & address field
|
||||
7C63- AD 21 7D LDA $7D21
|
||||
7C66- 85 D6 STA $D6 ; ($D6) = 3 = timeout * 256?
|
||||
;
|
||||
7C68- A0 80 LDY #$80 ; gap1 has gap count = 128
|
||||
7C6A- A9 00 LDA #$00
|
||||
7C6C- 85 D2 STA $D2 ; sector = 0
|
||||
7C6E- 4C 73 7C JMP $7C73
|
||||
|
||||
; write gap3 & address field
|
||||
7C71- A4 D4 LDY $D4 ; gap3_count
|
||||
;
|
||||
7C73- AE 23 7D LDX $7D23 ; slot*16
|
||||
7C76- 20 AE 7B JSR $7BAE ; write gap1|3 & address field
|
||||
7C79- 90 03 BCC $7C7E
|
||||
; error:
|
||||
7C7B- 4C 0E 7D JMP $7D0E
|
||||
; success:
|
||||
; write gap2, data field, data
|
||||
7C7E- AE 23 7D LDX $7D23
|
||||
7C81- 20 2E 7B JSR $7B2E
|
||||
7C84- E6 D2 INC $D2 ; inc write_sector
|
||||
7C86- A5 D2 LDA $D2
|
||||
7C88- C9 10 CMP #$10 ; done 16 sectors?
|
||||
7C8A- 90 E5 BCC $7C71 ; ... no, write next gap3 & sector
|
||||
|
||||
;
|
||||
; verify track
|
||||
;
|
||||
|
||||
7C8C- A0 0F LDY #$0F
|
||||
7C8E- 84 D2 STY $D2 ; write_sector = 15 (used as sector loop counter)
|
||||
7C90- AD 22 7D LDA $7D22 ; A = #$10 (constant)
|
||||
7C93- 8D 25 7D STA $7D25 ; Set retry count = #$10
|
||||
|
||||
; Fill sector_flag struct with #$10
|
||||
7C96- 99 26 7D STA $7D26,Y
|
||||
7C99- 88 DEY
|
||||
7C9A- 10 FA BPL $7C96
|
||||
|
||||
7C9C- A5 D4 LDA $D4 ; gap3_count
|
||||
7C9E- 38 SEC
|
||||
7C9F- E9 05 SBC #$05
|
||||
7CA1- A8 TAY
|
||||
|
||||
; Delay for: (gap3_count-5) * 40 cycles
|
||||
7CA2- 20 0E 7D JSR $7D0E ; 12cy / RTS
|
||||
7CA5- 20 0E 7D JSR $7D0E ; 12cy / RTS
|
||||
7CA8- 48 PHA ; 3
|
||||
7CA9- 68 PLA ; 4
|
||||
7CAA- EA NOP ; 2
|
||||
7CAB- EA NOP ; 2
|
||||
7CAC- 88 DEY ; 2
|
||||
7CAD- D0 F3 BNE $7CA2 ; 3 (taken)
|
||||
; = 40 cycles
|
||||
|
||||
7CAF- AE 23 7D LDX $7D23
|
||||
7CB2- 20 6A 7A JSR $7A6A ; Read address field
|
||||
7CB5- B0 3C BCS $7CF3
|
||||
7CB7- A5 D8 LDA $D8
|
||||
7CB9- F0 13 BEQ $7CCE ; read sector 0?
|
||||
; ... No:
|
||||
7CBB- C6 D4 DEC $D4 ; gap3_count--
|
||||
7CBD- A5 D4 LDA $D4
|
||||
7CBF- CD 1F 7D CMP $7D1F
|
||||
7CC2- B0 2F BCS $7CF3 ; rewrite track
|
||||
7CC4- 38 SEC ; error: gap3_count too small
|
||||
7CC5- 60 RTS
|
||||
|
||||
; Verify next sector
|
||||
7CC6- AE 23 7D LDX $7D23
|
||||
7CC9- 20 6A 7A JSR $7A6A ; Read address field
|
||||
7CCC- B0 1A BCS $7CE8
|
||||
;
|
||||
7CCE- AE 23 7D LDX $7D23
|
||||
7CD1- 20 07 7A JSR $7A07 ; Read sector data
|
||||
7CD4- B0 12 BCS $7CE8
|
||||
7CD6- A4 D8 LDY $D8 ; Y=read sector#
|
||||
7CD8- B9 26 7D LDA $7D26,Y
|
||||
7CDB- 30 0B BMI $7CE8 ; -ve if already read this sector
|
||||
7CDD- A9 FF LDA #$FF
|
||||
7CDF- 99 26 7D STA $7D26,Y ; sector_flag[Y] := #$FF
|
||||
7CE2- C6 D2 DEC $D2 ; write_sector--
|
||||
7CE4- 10 E0 BPL $7CC6
|
||||
7CE6- 18 CLC ; res = OK
|
||||
7CE7- 60 RTS
|
||||
;
|
||||
7CE8- CE 25 7D DEC $7D25 ; retry_count--
|
||||
7CEB- D0 D9 BNE $7CC6
|
||||
7CED- C6 D6 DEC $D6
|
||||
7CEF- D0 02 BNE $7CF3
|
||||
7CF1- 38 SEC ; error (timeout)
|
||||
7CF2- 60 RTS
|
||||
|
||||
; Retry 32 times to read sector #$0F
|
||||
; On success: rewrite track
|
||||
7CF3- AD 22 7D LDA $7D22 ; A = #$10 (constant)
|
||||
7CF6- 0A ASL ; A = #$20
|
||||
7CF7- 8D 25 7D STA $7D25 ; Set retry count = #$20
|
||||
;
|
||||
7CFA- AE 23 7D LDX $7D23
|
||||
7CFD- 20 6A 7A JSR $7A6A ; Read address field
|
||||
7D00- B0 06 BCS $7D08
|
||||
7D02- A5 D8 LDA $D8
|
||||
7D04- C9 0F CMP #$0F ; read sector == #$0F? (ie. last sector on track)
|
||||
7D06- F0 07 BEQ $7D0F ; ... yes: wait & rewrite track
|
||||
7D08- CE 25 7D DEC $7D25
|
||||
7D0B- D0 ED BNE $7CFA
|
||||
7D0D- 38 SEC ; error
|
||||
7D0E- 60 RTS
|
||||
;
|
||||
|
||||
; wait for 214 x 32-cycle nibbles
|
||||
7D0F- A2 D6 LDX #$D6 ; = 214
|
||||
7D11- 20 0E 7D JSR $7D0E ; 12cy / RTS
|
||||
7D14- 20 0E 7D JSR $7D0E ; 12cy / RTS
|
||||
7D17- 24 00 BIT $00 ; 3cy
|
||||
7D19- CA DEX ; 2cy
|
||||
7D1A- D0 F5 BNE $7D11 ; 3cy (2+1taken)
|
||||
; = 32
|
||||
; JMP to Write track and verify track
|
||||
7D1C- 4C 68 7C JMP $7C68
|
||||
; end
|
||||
|
||||
.data
|
||||
7D1F: 0E ; min gap3
|
||||
7D20: 1B ; max gap3 (gap3 >= 0x1B means DRIVE TOO SLOW)
|
||||
7D21: 03 ; timeout * 256
|
||||
7D22: 10 ; a constant
|
||||
7D23: 80 ; slot*10
|
||||
7D24: A0 ; gets init'd to #$50 (80)
|
||||
7D25: A0 ; retry count
|
||||
|
||||
; sector_flag[16]:
|
||||
7D26: A0 B1 C5 A0
|
||||
7D2A: A0 C4 A0 B0
|
||||
7D2E: 80 A0 A0 C3
|
||||
7D32: A0 A0 A0 A0
|
||||
|
||||
7D36: A0
|
||||
7D37: A0
|
||||
7D38: A0
|
||||
7D39: A0
|
||||
|
||||
; Symbol table:
|
||||
D0 kAA
|
||||
D1 w_Track
|
||||
D2 w_Sector
|
||||
D3 w_Volume
|
||||
D4 w_Gap3Count
|
||||
D5 r_Nib96Count
|
||||
D6 r_NibCount1Hi
|
||||
D7 r_Chksum
|
||||
D8 r_Sector
|
||||
D9 r_Track
|
||||
DA r_Volume
|
||||
DB r_TmpChksum
|
||||
DC r_NibCount2Hi
|
||||
DD r_Tmp4and4
|
||||
DE kVolNum01
|
||||
7900 FormatterDiskII
|
||||
7923 SeekTrack
|
||||
793A FormatDisk
|
||||
7982 WriteNextTrack
|
||||
79A2 WriteTrack
|
||||
79B5 CheckGap3Count
|
||||
79CB FindSector00Init
|
||||
79D1 FindSector00Cont
|
||||
79E7 VerifySector
|
||||
79EF NextTrack
|
||||
79F9 Done
|
||||
7A07 ReadSectorData
|
||||
7A6A ReadAddressField
|
||||
7AC6 SeekHalfTrack
|
||||
7B2E WriteGap2AndData
|
||||
7BA4 WriteNibble1a
|
||||
7BA5 WriteNibble1b
|
||||
7BAE CheckWriteProt
|
||||
7BB7 WriteGap0Or3AndAddress
|
||||
7C2C WriteNibble2a
|
||||
7C2D WriteNibble2b
|
||||
7C37 Unused3
|
||||
7C3A WaitA
|
||||
7C4B Data12_1
|
||||
7C57 Data12_2
|
||||
7C63 WriteAndVerifyTrack
|
||||
7C68 WriteGap1AndAddress2
|
||||
7C71 WriteGap3AndAddress
|
||||
7C8C VerifyTrack
|
||||
7C96 ResetSectorFlags
|
||||
7CA2 WaitGap3Count
|
||||
7CBB DecGap3Count
|
||||
7CC6 VerifyNextSector
|
||||
7CCE VerifyNextSector2
|
||||
7CE8 Retry
|
||||
7CF3 Retry2
|
||||
7CFA FindSector0FCont
|
||||
7D0E RTS
|
||||
7D0F RetryWait
|
||||
7D1F kMinGap3
|
||||
7D20 kMaxGap3
|
||||
7D21 kNibCountHi
|
||||
7D22 k10
|
||||
7D23 Slotx16
|
||||
7D24 HalfTrack
|
||||
7D25 RetryCount
|
||||
7D26 SectorFlags
|
||||
Binary file not shown.
Binary file not shown.
File diff suppressed because it is too large
Load Diff
Loading…
Reference in New Issue