mirror of https://github.com/a2-4am/4cade.git
50 lines
1.0 KiB
Plaintext
50 lines
1.0 KiB
Plaintext
;license:MIT
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;(c) 2021 by 4am
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!cpu 6502
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!to "build/FX.INDEXED/SHR.LR2",plain
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*=$A000
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shrlo = $301 ; $C8 bytes, indexed as shrlo-1,x
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shrhi = $38 ; $C8 bytes, indexed as shrhi-1,x
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!source "src/fx/macros.a"
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+COPY_TO_0 start, end
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+BUILD_SHR_LOOKUP_TABLES shrlo, shrhi
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;X=0
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+COPY_SCB_AND_PALETTES
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;WRITEAUXMEM active
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jmp loop1
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start
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!pseudopc 0 {
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loop1 ldy #1
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loop2 ldx #$C8
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loop3 lda shrlo-1, x
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sta <dst+1
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lda shrhi-1, x
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sta <dst+2
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lda (<dst+1), y
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dst sta $0000, y ; SMC
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dex
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bne loop3
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lda $C000
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bmi @exit
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iny
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iny
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cpy #$A0
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bcc loop2
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dec <loop1+1
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bpl loop1
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@exit
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rts
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}
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end
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; if zero page code gets too large, move shrhi to $201
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!if end-start > $38 {
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!error "code is too large: ends at ", end-start
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}
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