4字节除法.txt

MCS51四字节除法运算程序

;***************************************************************************** 
DIV4: 		
	  	CLR     7EH             ;4字节除法程序,被除数20H-23H,除数28H-2BH
        	MOV     R7,#03H		;商20H-23H,余数24H-27H
        	MOV     R0,#28H
DV0:
	    	MOV     A,@R0
        	INC     R0
        	ORL     A,@R0
        	JNZ     DV1
        	DJNZ    R7,DV0
        	SETB    7EH
        	SJMP    DV8
DV1:
	    	MOV     R6,#20H
        	CLR     C
DV2:
	    	MOV     R0,#20H
        	MOV     R7,#08H
DV3:
	    	MOV     A,@R0
        	RLC     A
        	MOV     @R0,A
        	INC     R0
        	DJNZ    R7,DV3
        	MOV     0F0H,C
        	CLR     C
        	MOV     R0,#24H
        	MOV     R1,#28H
        	MOV     R7,#04H
DV4:
	    	MOV     A,@R0
        	SUBB    A,@R1
        	MOV     @R0,A
        	INC     R0
        	INC     R1
        	DJNZ    R7,DV4
        	JNB     0F0H,DV5
        	CLR     C
        	SJMP    DV6
DV5:
	    	JNC     DV6
        	MOV     A,24H
        	ADD     A,28H
        	MOV     24H,A
        	MOV     A,25H
        	ADDC    A,29H
        	MOV     25H,A
        	MOV     A,26H
        	ADDC    A,2AH
        	MOV     26H,A
        	MOV     A,27H
        	ADDC    A,2BH
        	MOV     27H,A
DV6:
	    	CPL     C
        	DJNZ    R6,DV2
        	MOV     R0,#20H
        	MOV     R7,#04H
DV7:
	    	MOV     A,@R0
        	RLC     A
        	MOV     @R0,A
        	INC     R0
        	DJNZ    R7,DV7
DV8:    	
		RET
;***************************************************************************** 

F210:						;进制转换程序
        	MOV     24H,#00H		;十六进制数放在20H-23H
        	MOV     25H,#00H		;转换完成后十进制放在
        	MOV     26H,#00H		;DATA1-4
        	MOV     27H,#00H
	   	MOV     28H,#0E8H        	
        	MOV     29H,#03H
        	MOV     2AH,#00H
        	MOV     2BH,#00H
        	ACALL   DIX
        	MOV     DATA4,24H
        	MOV     28H,#64H
        	MOV     29H,#00H
        	ACALL   DIX
        	MOV     DATA3,24H
        	MOV     28H,#0AH
        	MOV	29H,#00H
        	ACALL   DIX
        	MOV     DATA2,24H
        	MOV     DATA1,20H
        	RET
;*****************************************************************************