;O NHO R5 CHUA GIO;O NHO R6 CHUA PHUT ;O NHO R7 CHUA GIAY;40 = DON VI GIAY;41 = CHUC GIAY;42 = DON VI PHUT ;43 = CHUC PHUT;44 = DON VI GIO;45 = CHUC GIOGIO EQU R5PHUT EQU R6GIAY EQU R7DVGIAY EQU 40HCGIAY EQU 41HDVPHUT EQU 42HCPHUT EQU 43HDVGIO EQU 44HCGIO EQU 45HTANG_PHUT EQU P3.0TANG_GIO EQU P3.1ORG 0000HMAIN:

MOV GIAY,#0MOV PHUT,#59MOV GIO,#23

HIENTHILAI:CALL TANG_THOI_GIANCALL DOIBCDMOV R0,#50

LAP:CALL HIENTHIDJNZ R0,LAPINC GIAYCJNE GIAY,#60,HIENTHILAIMOV GIAY,#0INC PHUTCJNE PHUT,#60,HIENTHILAIMOV PHUT,#0INC GIOCJNE GIO,#24,HIENTHILAI

JMP MAIN

DOIBCD:MOV A,GIOMOV B,#10DIV ABMOV DVGIO,BMOV CGIO,A

MOV A,PHUTMOV B,#10DIV ABMOV DVPHUT,BMOV CPHUT,A

MOV A,GIAYMOV B,#10

DIV ABMOV DVGIAY,BMOV CGIAY,A

RET

HIENTHI:

MOV P1,#01HMOV P0,DVGIAYCALL DELAYMOV P1,#02HMOV P0,CGIAYCALL DELAYMOV P1,#04HMOV P0,DVPHUTCALL DELAYMOV P1,#08HMOV P0,CPHUTCALL DELAYMOV P1,#10HMOV P0,DVGIOCALL DELAYMOV P1,#20HMOV P0,CGIOCALL DELAY

RETDELAY:

MOV TMOD,#01HMOV TH0,#HIGH(-3333)MOV TL0,#LOW(-3333)SETB TR0JNB TF0,$CLR TR0CLR TF0

RETTANG_THOI_GIAN:

JB TANG_PHUT,NEXT0INC PHUTCJNE PHUT,#60,NEXT0MOV PHUT,#0

NEXT0: JB TANG_GIO,OUTINC GIOCJNE GIO,#24,OUTMOV GIO,#0

OUT:RET

END