9999秒程序设计2.c

秒表程序

M0	EQU  30H						;M0为10MS
M1	EQU  31H						;M1为100MS
S0	EQU  32H						;S0为S
S1	EQU  33H						;S1为十S
S2	EQU  34H						;S2为百S
S3	EQU  35H						;S3为KS
ORG   00H 
LJMP  START
ORG   0BH
LJMP  INT_T0
START:;JB P3.0,DIR1
		;MOV DPTR,#TABLE2
		;SJMP DIR 
DIR:	MOV DPTR,#TABLE 
		MOV M0,#00H
		MOV M1,#00H 			
		MOV S0,#00H				
		MOV S1,#00H				
		MOV S2,#00H				
		
		MOV P0,#0FFH
		MOV TMOD,#09H
		MOV TH0, #0D8H
		MOV TL0, #0F5H
		SETB TR0
		SETB ET0
		SETB EA
REL : JB P3.4,DIR
		LCALL DELAY10MS
		JB P3.4,DIR
M_0: 
   	MOV A,M0 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#10H
		MOV A,M0
		CJNE A,#0AH,M_1
		MOV M0,#00H
		INC M1	
M_1:     
		MOV A,M1 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#20H
		MOV A,M1
		CJNE A,#0AH,S_0
		MOV M1,#00H
		INC S0
S_0: 
   	MOV A,S0 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#01H
		MOV A, S0
		CJNE A,#0AH,S_1
		MOV S0,#00H
		INC S1
S_1:    
		MOV A,S1 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#02H
		MOV A,S1
		CJNE A,#0AH,S_2
		MOV S1,#00H
		CPL P1.3
		INC S2
S_2:     
		MOV A,S2 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#04H
D:		CLR P0.7 
		MOV A, S2
		CJNE A,#0AH,S_3
		MOV S2,#00H
		INC S3
S_3:  
		MOV A,S3 
	   MOVC A,@A+DPTR 
		MOV P2,#00H
		MOV P0,A 
		MOV P2,#08H 
		MOV A, S3 
		CJNE A,#0AH,M_0
		MOV S3,#00H
		LJMP M_0 
INT_T0:
		INC M0
		MOV TH0,#0D8H
		MOV TL0,#0F5H
		RETI	
DELAY10MS:
		MOV R0,#20
L1:	MOV R1,#248
		DJNZ R1,$
		DJNZ R0,L1
		RET	 
TABLE:
		DB 0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H
					;40H,79H,24H,30H,19H,12H,02H,78H,00H,10H

		END