mirror of https://github.com/RevCurtisP/C02.git
21 lines
681 B
Plaintext
21 lines
681 B
Plaintext
;Assembly Header Include File for platforms
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;that do not have PRBYTE amnd PRHEX routines in ROM
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;Print Byte as Two-Digit Hex Number to Console
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PRBYTE: PHA ;Save Accumulater
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LSR ;Shift Hi Nybble to Low Nybble
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LSR
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LSR
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LSR
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JSR PRHEX ; and Print it
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PLA ;Restore Accumulator
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; and fall into prhex
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;Print Low Nybble as Hex Digit to Console
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PRHEX: AND #$0F ;Strip High Nybble
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CMP #$0A ;If Low Nybble >= 10
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BCC PRHEXC ;
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ADC #$06 ; Convert ':' to 'A'...
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PRHEXC: ADC #$30 ;Convert to ASCII Character
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JMP PUTCHR ;Print Hex Digit and Return
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