;1.0850694us
;八同相雙向三態(tài)緩沖器／驅(qū)動器芯片74LS245
;


ORG 0000H
LJMP MAIN

ORG 5000H
MAIN:MOV R0,#4
MOV R1,#4
CLR P1.0  ;light red led
CLR P1.5
ACALL DELAY1S  

START:SETB P1.0    ;主路紅燈滅
CLR P1.2         ;主路綠燈亮
ACALL DELAY20S    ;亮20秒

SETB P1.2          ;主路綠燈滅
LOP1:CLR P1.1    ;主路黃燈閃爍4次（黃燈亮）
ACALL DELAY500MS   
SETB P1.1          ;黃燈滅
ACALL DELAY500MS
DJNZ R0,LOP1
CLR P1.1         ;黃燈亮第5次 
ACALL DELAY500MS
SETB P1.1          ;黃燈滅
CLR P1.0         ;主路紅燈亮
CLR P1.7         ;支路綠燈亮
SETB P1.5
ACALL DELAY10S

SETB P1.7          ;支路綠燈滅
LOP2:CLR P1.6    ;主路黃燈閃爍4次
ACALL DELAY500MS
SETB P1.6
ACALL DELAY500MS
DJNZ R1,LOP2
CLR P1.6
ACALL DELAY500MS
SETB P1.6
CLR P1.5
JMP START

DELAY500MS:MOV R2,#255
OUTLOP1:MOV R3,#255
LOOP1:NOP
NOP
NOP
NOP
NOP
DJNZ R2,LOOP1
DJNZ R3,OUTLOP1
RET

DELAY1S:ACALL DELAY500MS
ACALL DELAY500MS
RET

DELAY10S:MOV R4,#10
OUTLOP2:ACALL DELAY1S
DJNZ R4,OUTLOP2
RET

DELAY20S:ACALL DELAY10S
ACALL DELAY10S
RET