MAIN: MOV SP,#60H
PTOM: MOV R0,#00H
MOV R1,#10H
MOV R2,#20H
MOV R3,#30H
MOV R4,#40H
MOV R5,#50H
MOV R6,#60H
MOV R7,#70H
MOV A,#92H ;方式0,A、B口输入,C口输出
MOV DPTR,#CON
MOVX @DPTR,A
LOOP:
MOV DPTR,#PB8255
MOVX A,@DPTR
PB0: CJNE A,#0FEH,PB1
CJNE R0,#0FH,UNFULL
MOV R0,#00H
UNFULL:INC R0
MOV A,R0
AJMP DISPLAY
PB1: CJNE A,#0FDH,PB2
CJNE R1,#01FH,UNFULL1
MOV R1,#00H
UNFULL1:INC R1
MOV A,R1
AJMP DISPLAY
PB2: CJNE A,#0FBH,PB3
CJNE R2,#02FH,UNFULL2
MOV R2,#00H
UNFULL2:INC R2
MOV A,R2
AJMP DISPLAY
PB3: CJNE A,#0F7H,PB4
CJNE R3,#3FH,UNFULL3
MOV R3,#00H
UNFULL3:INC R3
MOV A,R3
AJMP DISPLAY
PB4: CJNE A,#0EFH,PB5
CJNE R4,#04FH,UNFULL4
MOV R4,#00H
UNFULL4:INC R4
MOV A,R4
AJMP DISPLAY
PB5: CJNE A,#0DFH,PB6
CJNE R5,#05FH,UNFULL5
MOV R5,#00H
UNFULL5:INC R5
MOV A,R5
AJMP DISPLAY
PB6: CJNE A,#0BFH,PB7
CJNE R6,#06FH,UNFULL6
MOV R6,#00H
UNFULL6:INC R6
MOV A,R6
AJMP DISPLAY
PB7: CJNE A,#07FH,LOP
CJNE R7,#07FH,UNFULL7
MOV R7,#00H
UNFULL7:INC R7
MOV A,R7
AJMP DISPLAY
DISPLAY:MOV DPTR,#PA8255
MOVX @DPTR,A
LOP: AJMP LOOP
END