c04.asm

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;	“探索式”	实验四  并行I/O口扩展实验


;文件名:MCS51\C04.ASM

	ORG 0000H
LOOP0:	MOV DPTR,#0b000H    ;读出74LS244状态
	MOVX A,@DPTR
	MOV DPTR,#0a000H   ;送74LS273驱动发光二极管
	MOVX @DPTR,A
	SJMP LOOP0