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https://github.com/fadden/6502bench.git
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42 lines
1.1 KiB
ArmAsm
42 lines
1.1 KiB
ArmAsm
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; Copyright 2018 faddenSoft. All Rights Reserved.
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; See the LICENSE.txt file for distribution terms (Apache 2.0).
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;
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; Assembler: cc65
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;
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; Both cc65 (2.17) and Merlin32 (1.0) have problems computing branches that
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; wrap around a bank (e.g. from $0010 to $ffd0). cc65 is slightly less
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; egregious in that a workaround is possible: if you specify a label that
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; is in range, and then an offset, it will generate code.
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;
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; 6502 version
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.setcpu "6502"
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.org $1000
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jmp zero
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.org $0000
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zero: bit a:zero
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low: lda zero
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lda low
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bne low-$40 ;reference symbol
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bmi low-$40 ;EDIT: format as hex
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bvs more
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bvc more1
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lodat: .byte $00,$01,$02 ;EDIT: set label
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more: lda more-2
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clc
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bcc zero-$40 ;branch to high
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.org $0080
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more1: bit a:more1
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jmp end
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.org $ffc0
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high:
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bit high
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clc
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bcc high+$43 ;branch to low
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end: rts
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