ldx #0 lda #0 loop: adc 1 sta $200,x sta $300,x sta $400,x sta $500,x inx cpx #$ff bne loop
ldy #0 loopx: iny tya ldx #0 loop: adc 1 sta $200,x sta $300,x sta $400,x sta $500,x inx cpx #$ff bne loop jmp loopx
C64 (Commodore) - Console approach - 8Bit 1982+
6502asm.com v1.2 - World's first fantasy console!
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The Visual 6502
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The designers figured that you'd use X and Y for looping, indexing etc, and use A for adding and subtracting, shifts etc. So they saw a need for INX and INY, but didn't see a enough of a need for an instruction to increment or decrement the accumulator.
65C02
@MauryMarkowitz There are a lot of instructions that could be added to the 6502 to decrease code size and/or increase performance but weren't. The designers were trying to make a cheap microprocessor, not a fully featured one and they drew their line with
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