A51 MACRO ASSEMBLER  EXTERNAL_INTERRUPT                                                   07/29/2006 19:31:20 PAGE     1


MACRO ASSEMBLER A51 V8.00
OBJECT MODULE PLACED IN External Interrupt.OBJ
ASSEMBLER INVOKED BY: e:\Program Files\Keil\C51\BIN\A51.EXE External Interrupt.asm SET(SMALL) DEBUG EP

LOC  OBJ            LINE     SOURCE

  0090                 1     LED             BIT             P1.0
  0030                 2     LEDBUF  EQU             30H
0000                   3                     ORG             00H
0000 020006            4                     LJMP    START
0003                   5                     ORG             03H
0003 020013            6                     LJMP    INTERRUPT
0006 C230              7     START:  CLR             LEDBUF
0008 C290              8                     CLR             LED
000A 758801            9                     MOV             TCON,#01H       ;外部中斷0下降沿觸發(fā)
000D 75A881           10                     MOV             IE,#81H         ;打開外部中斷允許位（EX0）
                      11                                                             ;及總中斷允許位（EA）
0010 020010           12                     LJMP    $                       ;等待中斷
0013                  13     INTERRUPT:
0013 C0D0             14                     PUSH    PSW                     ;保護(hù)現(xiàn)場(chǎng)
0015 B230             15                     CPL             LEDBUF          ;取反LED
0017 A230             16                     MOV             C,LEDBUF
0019 9290             17                     MOV             LED,C
001B D0D0             18                     POP             PSW                     ;恢復(fù)現(xiàn)場(chǎng)
001D 32               19                     RETI
                      20                     END
A51 MACRO ASSEMBLER  EXTERNAL_INTERRUPT                                                   07/29/2006 19:31:20 PAGE     2

SYMBOL TABLE LISTING
------ ----- -------


N A M E             T Y P E  V A L U E   ATTRIBUTES

IE . . . . . . . .  D ADDR   00A8H   A   
INTERRUPT. . . . .  C ADDR   0013H   A   
LED. . . . . . . .  B ADDR   0090H.0 A   
LEDBUF . . . . . .  N NUMB   0030H   A   
P1 . . . . . . . .  D ADDR   0090H   A   
PSW. . . . . . . .  D ADDR   00D0H   A   
START. . . . . . .  C ADDR   0006H   A   
TCON . . . . . . .  D ADDR   0088H   A   


REGISTER BANK(S) USED: 0 

ASSEMBLY COMPLETE.  0 WARNING(S), 0 ERROR(S)