     $E9C9/59849:   Get data byte from bus

    Jump from $E884, $EA44:

    E9C9: A9 08     LDA #$08
    E9CB: 85 98     STA $98         ; bit counter for serial output

    Jump from $E9D5:

    E9CD: 20 59 EA  JSR $EA59       ; check EOI
    E9D0: 20 C0 E9  JSR $E9C0       ; read IEEE port
    E9D3: 29 04     AND #$04        ; CLOCK IN?
    E9D5: D0 F6     BNE $E9CD       ; no, wait
    E9D7: 20 9C E9  JSR $E99C       ; DATA OUT, bit '1'
    E9DA: A9 01     LDA #$01
    E9DC: 4C 20 FF  JMP $FF20       ; set timer

    Jump from $E9EE, $FF2C:

    E9DF: 20 59 EA  JSR $EA59       ; check EOI
    E9E2: AD 0D 18  LDA $180D
    E9E5: 29 40     AND #$40        ; timer run down?
    E9E7: D0 09     BNE $E9F2       ; yes, EOI
    E9E9: 20 C0 E9  JSR $E9C0       ; read IEEE port
    E9EC: 29 04     AND #$04        ; CLOCK IN?
    E9EE: F0 EF     BEQ $E9DF       ; no, wait
    E9F0: D0 19     BNE $EA0B

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