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Routine $0745:   Wait for next sector start, set Job #1, set [$1D], set [$11], get Track Key.

If call to $0745: Wait for next sector start, set Job #1 to execute, set [$1D], set [$11],
                  get Key for current Track.
If call to $075D: Set [$1D], set [$11], get Key for current Track.
If jump to $0764: Set [$11], get Key for current Track.
If jump to $0769: Get Key for current Track.


JSR from $068E:

0745: A5 0A     LDA $0A
0747: 30 2D     BMI $0776

0749: 20 26 07  JSR $0726      ; Counts the data bytes (returned in A,Y) until next SYNC is detected. CF:=1.
074C: C0 18     CPY #$18       ; compare number of data bytes with $18
074E: 90 26     BCC $0776      ;   branch if <$18

0750: A2 D0     LDX #$D0
0752: 86 01     STX $01        ; set Job #1 to $D0 (execute $0400) again
0754: 20 3F 07  JSR $073F      ; measure length of next following SYNC mark (in X)
0757: E0 2A     CPX #$2A       ; compare SYNC length with $2A
0759: 90 22     BCC $077D      ;   branch if <$2A

075B: 86 11     STX $11        ; [$11]:= SYNC length

JSR from $058C:

075D: AD 50 01  LDA $0150
0760: 85 1D     STA $1D        ; [$1D]:= [$0150]
0762: A5 11     LDA $11

Jump from $0555:

0764: 38        SEC
0765: E5 1D     SBC $1D
0767: 85 11     STA $11        ; [$11]:= A - [$1D]

Jump from $06F0:

0769: A6 22     LDX $22
076B: E0 13     CPX #$13       ; compare [$22] with 19
076D: 90 02     BCC $0771      ;   branch if <19

076F: CA        DEX
0770: CA        DEX

Jump from $076D:

0771: BD 52 01  LDA $0152,X    ; get Key for current Track (read from Track 36 Key Sector)
0774: 85 0E     STA $0E        ; [$0E]:= Key (~number of #$7B's in extra sector)

Jump from $0747, $074E, $0781:

0776: A9 EE     LDA #$EE       ; set [$1C0C]:= 11101110b (111 = CA2+CB2 High output,
0778: 8D 0C 1C  STA $1C0C      ;                            0 = CA1+CB1 Negative active edge )
077B: 18        CLC
077C: 60        RTS

Jump from $076D:

077D: 66 12     ROR $12
077F: C6 D4     DEC $D4
0781: 10 F3     BPL $0776

Jump from $0713:

0783: 4C D5 07  JMP $07D5      ; error: branch to exit of RapidLok - Avoid this!!!

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