mirror of
https://github.com/nathanriggs/AppleIIAsm-Collection.git
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53 lines
1.3 KiB
Plaintext
53 lines
1.3 KiB
Plaintext
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*``````````````````````````````*
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* DISKOP : DISK OPERATION RWTS *
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*- -*
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* GENERAL PURPOSE ROUTINE FOR *
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* READING AND WRITING TO A *
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* DISK VIA TRACKS AND SECTORS. *
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*- -*
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* CLOBBERS: *
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* *
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* FLAGS: ????---- REG: AXYM *
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*- -*
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* CYCLES: ??? *
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* SIZE: *
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*- -*
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* USAGE: *
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* *
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*- -*
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* ENTRY *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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*- -*
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* EXIT *
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* *
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* TOP OF STACK *
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* *
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* LOW BYTE OF RETURN ADDRESS *
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* HI BYTE OF RETURN ADDRESS *
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* *
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* .Y = CLOBBERED *
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* .X = CLOBBERED *
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* .A = CLOBBERED *
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*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
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*
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DISKOP
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*
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:CLEAR
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LDA #00
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STA IOB_EVOL
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*
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LDA #>IOB
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LDY #<IOB
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JSR RWTS
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BCC :EXIT
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:ERR LDA IOB_ERR
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LDX #00
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STX $48
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:EXIT RTS
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*
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