键盘扫描汇编.asm

采用汇编加C语言书写的LED程序

查询工作方式进行扫描键盘


 	KEY1: ACALL KS1
	JNZ KEY2
	KEY3: DELAY6MS
	JMP KEY1
	KEY2: ACALL DELAT12MS
		ACALL KS1
		JZ KEY6
		AJMP KEY3
	KEY6:	MOV A,#FEH
		MOV R1,A
		MOV R2,#0	//R2保存列号

   	KEY5:	MOV DPTR,#0700H
		MOV @DPTR,A
		INC DPTR
		INC DPTR
		MOV A,@DPTR
		JB ACC.0,ROW2
		MOV A,#0H
		ACALL KLP
	ROW2:   JB ACC.1,ROW3
		MOV A,#08H
		ACALL KLP
	ROW3:	JB ACC.2,ROW4
		MOV A,#10H
		ACALL KLP
	ROW4:   JB ACC.3,KEY4
		MOV A,#18H
	KLP:	ADD A, R2
		PUSH ACC
	KEY3:	ACALL KS1
		JNZ KEY3
		POP ACC
		RET
	KEY4:	MOV A,R1
		JNB ACC.7,KEY1 //判断列扫描是否完成
		INC R2
		RL A
		MOV R1,A
		AJMP KEY5
	KS1:    MOV DPTR,#O7OOH
	    	MOV A,#00H
		MOV @PDTR,A
		INC DPTR
		INC DPTR
		MOV A,@DPTR
		ANL A,#0FH
		CPL A
		RET
	DELAY6MS: MOV R3,#0CH
	     TM:  MOV R4,#FFH
	    TM2:  DJNZ R4,TM2
		  DJNZ R3,TM
		  RET
	DELAY12MS: MOV R3,#18H
	     TM12:  MOV R4,#FFH
	    TM24:  DJNZ R4,TM24
		  DJNZ R3,TM12
		  RET