SECOND  	EQU 30H 
MINITE  		EQU 31H 
HOUR    	EQU 32H 
HOURK   	BIT P0.2 
MINITEK 	BIT P0.1 
SECONDK 	BIT P0.0 
DISPBUF 		EQU 40H 
DISPBIT 		EQU 48H 
T2SCNTA 	EQU 49H 
T2SCNTB 	EQU 4AH 
TEMP    		EQU 4BH 
  
        ORG 00H 
        LJMP START 
        ORG 0BH 
        LJMP INT_T0 
START:  MOV SECOND,#00H 
        MOV MINITE,#00H 
        MOV HOUR,#12 
        MOV DISPBIT,#00H 
        MOV T2SCNTA,#00H 
        MOV T2SCNTB,#00H 
        MOV TEMP,#0FEH 
        LCALL DISP 
        MOV TMOD,#01H 
        MOV TH0,#(65536-2000) / 256 
        MOV TL0,#(65536-2000) MOD 256 
        SETB TR0 
        SETB ET0 
        SETB EA 
WT:     JB SECONDK,NK1 
        LCALL DELY10MS 
        JB SECONDK,NK1 
        INC SECOND 
        MOV A,SECOND 
        CJNE A,#60,NS60 
        MOV SECOND,#00H 
NS60:   LCALL DISP 
        JNB SECONDK,$ 
NK1:    JB MINITEK,NK2 
        LCALL DELY10MS 
        JB MINITEK,NK2 
        INC MINITE 
        MOV A,MINITE 
        CJNE A,#60,NM60 
        MOV MINITE,#00H 
NM60:   LCALL DISP 
        JNB MINITEK,$ 
NK2:    JB HOURK,NK3 
        LCALL DELY10MS 
        JB HOURK,NK3 
        INC HOUR 
        MOV A,HOUR 
        CJNE A,#24,NH24 
        MOV HOUR,#00H 
NH24:   LCALL DISP 
        JNB HOURK,$ 
NK3:    LJMP WT 
DELY10MS: 
        MOV R6,#10 
D1:     MOV R7,#248 
        DJNZ R7,$ 
        DJNZ R6,D1 
        RET 
DISP:   
        MOV A,#DISPBUF 
        ADD A,#8 
        DEC A 
        MOV R1,A 
        MOV A,HOUR 
        MOV B,#10 
        DIV AB 
        MOV @R1,A 
        DEC R1 
        MOV A,B 
        MOV @R1,A 
        DEC R1 
        MOV A,#10 
        MOV@R1,A 
        DEC R1 
        MOV A,MINITE 
        MOV B,#10 
        DIV AB 
        MOV @R1,A 
        DEC R1 
        MOV A,B 
        MOV @R1,A 
        DEC R1 
        MOV A,#10 
        MOV@R1,A 
        DEC R1 
        MOV A,SECOND 
        MOV B,#10 
        DIV AB 
        MOV @R1,A 
        DEC R1 
        MOV A,B 
        MOV @R1,A 
        DEC R1 
        RET 
INT_T0: 
        MOV TH0,#(65536-2000) / 256 
        MOV TL0,#(65536-2000) MOD 256 
 MOV A, #0FFH
        MOV P3,A 

        MOV A,#DISPBUF 
        ADD A,DISPBIT 
        MOV R0,A 
        MOV A,@R0 
        MOV DPTR,#TABLE 
        MOVC A,@A+DPTR 
        MOV P1,A 
        MOV A,DISPBIT 
        MOV DPTR,#TAB 
        MOVC A,@A+DPTR 
        MOV P3,A 
        INC DISPBIT 
        MOV A,DISPBIT 
        CJNE A,#08H,KNA 
        MOV DISPBIT,#00H 
KNA:    INC T2SCNTA 
        MOV A,T2SCNTA 
        CJNE A,#100,DONE 
        MOV T2SCNTA,#00H 
        INC T2SCNTB 
        MOV A,T2SCNTB 
        CJNE A,#05H,DONE 
        MOV T2SCNTB,#00H 
        INC SECOND 
        MOV A,SECOND 
        CJNE A,#60,NEXT 
        MOV SECOND,#00H 
        INC MINITE 
        MOV A,MINITE 
        CJNE A,#60,NEXT 
        MOV MINITE,#00H 
        INC HOUR 
        MOV A,HOUR 
        CJNE A,#24,NEXT 
        MOV HOUR,#00H 
NEXT:   LCALL DISP 
DONE:   RETI 
TABLE:  DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H,7FH,6FH,40H 
TAB:    DB 0FEH,0FDH,0FBH,0F7H,0EFH,0DFH,0BFH,07FH 
        END