51单片机的一个简单程序

ORG 0000H

LJMP MAIN

ORG 0030H

MAIN:

MOV A,P0

ANL A,#1EH

CJNE A,#02H,MAIN1

SETB P1.1

CLR P1.2

CLR P1.8

SJMP MAIN

MAIN1:

CJNE A,#04H,MAIN2

CLR P1.1

SETB P1.2

CLR P1.8

SJMP MAIN

MAIN2:

CJNE A,#1EH,MAIN3

CLR P1.1

CLR P1.2

SETB P1.8

SJMP MAIN

MAIN3:

CLR P1.1

CLR P1.2

CLR P1.8

LJMP MAIN

END

(1)

MOV A,30H

ANL A,#3CH

RL A,#02H

MOV 33H,A

MOV A,31H

ANL A,#O3H

RL A,#02H

ORL 33H,A

MOV A,32H

ANL A,#0C0H

RL A,#06H

ORL 33H,A

2:

MOV A,DPH

每个灯亮1秒，每个灯闪亮频率为5次/秒。

下列程序，在PROTEUS中仿真通过.

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ORG 0000H

LJMP MAIN

ORG 000BH

LJMP T0_INT

ORG 0030H

MAIN:

MOV SP, #7FH

MOV TMOD,#01H

MOV TL0, #LOW(65536-50000)

MOV TH0, #HIGH(65536-50000)

SETB TR0

MOV IE, #82H

MOV R2, #2

MOV R3, #10

MOV R4, #0

M_LOOP:

LJMP M_LOOP等待中断，一切闪动、移位，都在中断里面解决

----------------------------------------------------------------

T0_INT:

MOV TL0, #LOW(65536-50000)

MOV TH0, #HIGH(65536-50000)

DJNZ R2, T0_END

MOV R2, #2加大此数字，如改为8，可降低速度，便于观察.

INC R4

DJNZ R3, FLASH 100ms减一次一.

MOV R3, #10

INC R6 1s加一次一

FLASH:

MOV A, R6

ANL A, #7

MOV R5, A 0~7, 1s换一次位.

INC R5

MOV A, R4

MOV C, ACC.0

MOV A, #255

MOV P1, A 关显示

T0_LOOP:

RLC A

DJNZ R5, T0_LOOP

MOV P1, A

T0_END:

RETI

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END

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