ORG 0000H
SJMP START
ORG 0080H
LED0 EQU 40H
LED1 EQU 41H
LED2 EQU 42H
LED3 EQU 43H ;存放四个数码管的段码
ADC EQU 45H ;存放转AD换后的数
STR BIT P3.0
OE BIT P3.1
EOC BIT P3.2
START: MOV LED0,#00H ;清零
MOV LED1,#00H
MOV LED2,#00H
MOV LED3,#00H
MOV P1,#00H
MOV P2,#0F1H
MOV P3,#9FH
MOV R1,#00H
MOV DPTR,#TABLE ;送段码首地址到DPTR
WAIT: CLR STR
SETB STR
CLR STR ;产生下降沿启动AD转换
JNB EOC,$ ;等待转换结束
SETB OE ; 允许输出转换结果
MOV ADC,P0 ;存储转换结果
CLR OE
MOV A,ADC
MOV R2,#00H
CLR C
RLC A
JNC GO
MOV R2,#01H
GO: MOV B,#51 ;数据送显示前的处理
DIV AB
CJNE R2,#01H,MEI
ADD A,#05H
MEI: MOV LED2,A ;测量结果送到数码管显示
MOV A,B
MOV B,#5
DIV AB
MOV LED1,A
MOV LED0,B
MOV A,LED2
CJNE A,#10,WU
AJMP NEXT
WU: AJMP NEXT1
NEXT: MOV LED0,#00H
MOV LED1,#00H
MOV LED2,#00H
MOV LED3,#01H
NEXT1: CJNE R1,#03H,NEXT2
LCALL DISP3
JB P3.7,WAIT
LJMP KEY
NEXT2: CJNE R1,#02H,NEXT3
LCALL DISP2
JB P3.7,WAIT
LJMP KEY
NEXT3: LCALL DISP1
JB P3.7,WAIT
LJMP KEY
DISP1: MOV A,LED0 ;显示子程序
MOVC A,@A+DPTR
CLR P2.7
MOV P1,A
LCALL DELAY
SETB P2.7
MOV A,LED1
MOVC A,@A+DPTR
CLR P2.6
MOV P1,A
LCALL DELAY
SETB P2.6
MOV A,LED2
MOVC A,@A+DPTR
CLR P2.5
ORL A,#80H
MOV P1,A
LCALL DELAY
SETB P2.5
MOV A,LED3
MOVC A,@A+DPTR
CLR P2.4
MOV P1,A
LCALL DELAY
SETB P2.4
RET
DISP2: MOV A,LED0
MOVC A,@A+DPTR
CLR P2.7
MOV P1,A
LCALL DELAY
SETB P2.7
MOV A,LED1
MOVC A,@A+DPTR
CLR P2.6
MOV P1,A
LCALL DELAY
SETB P2.6
MOV A,LED2
MOVC A,@A+DPTR
CLR P2.5

	 MOV    P1,A
	 LCALL   DELAY
	 SETB    P2.5
	 MOV   A,LED3
	 MOVC   A,@A+DPTR
	 CLR    P2.4
	 ORL    A,#80H
	 MOV    P1,A
	 LCALL   DELAY
	 SETB   P2.4
	 RET

DISP3: MOV A,LED0
MOVC A,@A+DPTR
CLR P2.7
MOV P1,A
LCALL DELAY
SETB P2.7
MOV A,LED1
MOVC A,@A+DPTR
CLR P2.6
ORL A,#80H
MOV P1,A
LCALL DELAY
SETB P2.6
MOV A,LED2
MOVC A,@A+DPTR
CLR P2.5

	 MOV    P1,A
	 LCALL   DELAY
	 SETB    P2.5
	 MOV   A,LED3
	 MOVC   A,@A+DPTR
	 CLR    P2.4
	 MOV    P1,A
	 LCALL   DELAY
	 SETB   P2.4
	 RET 		   

KEY: JB P3.7,$ ;按键程序
KEY1: JNB P3.7,$
INC R1
CJNE R1,#04H,A3
MOV R1,#01H
A3: CJNE R1,#01H,L1
LJMP LC1
L1: CJNE R1,#02H,L2
LJMP LC2
L2: CJNE R1,#03H,$
LJMP LC3
LC1: CLR P2.1
CLR P2.2
CLR P3.5
CLR P3.6
SETB P2.0
SETB P3.4
LJMP WAIT
LC2: CLR P2.0
CLR P2.2
CLR P3.4
CLR P3.6
SETB P2.1
SETB P3.5
LJMP WAIT
LC3: CLR P2.0
CLR P2.1
CLR P3.4
CLR P3.5
SETB P2.2
SETB P3.6
LJMP WAIT
DELAY: MOV R6,#10 ;延时子程序
D1: MOV R7,#250
DJNZ R7,$
DJNZ R6,D1
RET
TABLE:DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH ;字型码表
END