DATA COPY

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FlameCyclone
Posts: 15
Joined: Fri Jun 02, 2017 2:45 am

DATA COPY

Post by FlameCyclone »

Code: Select all

;[FC][数据复制]
;FlameCyclone 2017.6.11

 .ORG $D000

COPY_FROM_L = $40
COPY_FROM_H = $41
COPY_TO_L = $42
COPY_TO_H = $43


COPY_DATA:
 PHA
 TXA
 PHA
 TYA
 PHA
 LDX #$00
 LDY #$00
COPY_TO_SET:   ;目的开始地址设置
 LDA COPY_TO_ADDR+1
 STA COPY_TO_L
 LDA COPY_TO_ADDR
 STA COPY_TO_H

COPY_FROM_SET:   ;数据源开始地址设置
 LDA COPY_FROM_ADDR+1
 STA COPY_FROM_L
 LDA COPY_FROM_ADDR
 STA COPY_FROM_H
 
COPY_START:   ;复制开始
 LDA COPY_TO_L
 CMP COPY_OVER_ADDR+1
 BNE COPY_DATA_START
 LDA COPY_TO_H
 CMP COPY_OVER_ADDR
 BEQ COPY_OVER
COPY_DATA_START:   ;开始复制数据
 LDA (COPY_FROM_L),Y
 STA (COPY_TO_L),Y
 JSR COPY_TO_ADD
 JSR COPY_FROM_ADD
 JMP COPY_START

COPY_OVER:    ;结束数据复制
 LDA (COPY_FROM_L),Y
 STA (COPY_TO_L),Y
 PLA
 TAY
 PLA
 TAX
 PLA
 RTS
 
COPY_FROM_ADD:    ;原地址递增
 INC COPY_FROM_L
 BNE COPY_FROM_ADD_RTS
 INC COPY_FROM_H
COPY_FROM_ADD_RTS:
 RTS
 
COPY_TO_ADD:    ;目的地址递增
 INC COPY_TO_L
 BNE COPY_TO_ADD_RTS
 INC COPY_TO_H
COPY_TO_ADD_RTS:
 RTS

COPY_FROM_ADDR:    ;数据源开始地址
 .DB $C0,$00
COPY_TO_ADDR:    ;目的开始地址
 .DB $60,$00
COPY_OVER_ADDR:    ;目的结束地址
 .DB $7F,$FF
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