5．程序框圖

圖4.9.2

6．匯編源程序

ID EQU 30H

SP1 BIT P3.7

L1 BIT P1.0

L2 BIT P1.1

L3 BIT P1.2

L4 BIT P1.3

ORG 0

MOV ID,#00H

START: JB K1,REL

LCALL DELAY10MS

JB K1,REL

INC ID

MOV A,ID

CJNE A,#04,REL

MOV ID,#00H

REL: JNB K1,$

MOV A,ID

CJNE A,#00H,IS0

CPL L1

LCALL DELAY

SJMP START

IS0: CJNE A,#01H,IS1

CPL L2

LCALL DELAY

SJMP START

IS1: CJNE A,#02H,IS2

CPL L3

LCALL DELAY

SJMP START

IS2: CJNE A,#03H,IS3

CPL L4

LCALL DELAY

SJMP START

IS3: LJMP START

DELAY10MS: MOV R6,#20

LOOP1: MOV R7,#248

DJNZ R7,$

DJNZ R6,LOOP1

RET

DELAY: MOV R5,#20

LOOP2: LCALL DELAY10MS

DJNZ R5,LOOP2

RET

END