ex01.lst

c51 led程序

A51 MACRO ASSEMBLER  EX01                                                                 06/08/2005 21:41:27 PAGE     1


MACRO ASSEMBLER A51 V7.03
OBJECT MODULE PLACED IN ex01.OBJ
ASSEMBLER INVOKED BY: C:\Keil\C51\BIN\A51.EXE ex01.asm SET(SMALL) DEBUG EP

LOC  OBJ            LINE     SOURCE

                       1     
                       2     
                       3     
                       4     
                       5     
                       6     
                       7     
                       8     
                       9     
                      10     
                      11     
                      12     
                      13     
                      14     
0000                  15             ORG     0000H
0000 020030           16             LJMP    MAIN
0030                  17             ORG     30H
0030                  18     MAIN:
0030 7580FE           19             MOV     P0,#0FEH                ; 初始点亮LED1 
0033 7FFE             20             MOV     R7,#0FEH                ; 保存P0
0035                  21     MAIN_LP:
0035 113E             22             CALL    DELAY                   ; 延时
0037 EF               23             MOV     A,R7                    ; 
0038 23               24             RL      A                       ; 循环移位
0039 FF               25             MOV     R7,A                    ; 保存到R7
003A F580             26             MOV     P0,A                    ; 点亮下一个LED
003C 80F7             27             JMP     MAIN_LP                 ; 不停循环
                      28     
                      29     ;===========================================================
003E                  30     DELAY:                                  ; 延时子程序
003E 78A0             31             MOV     R0,#0A0H                ; 可以尝试修改R0，R1的值，观察现象变化
0040 79FF             32             MOV     R1,#0FFH
0042                  33     DLY_LP:
0042 00               34             NOP
0043 00               35             NOP
0044 D8FC             36             DJNZ    R0,DLY_LP
0046 78FF             37             MOV     R0,#0FFH
0048 D9F8             38             DJNZ    R1,DLY_LP 
004A 22               39             RET
                      40             
                      41             END
A51 MACRO ASSEMBLER  EX01                                                                 06/08/2005 21:41:27 PAGE     2

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


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

DELAY. . . . . . .  C ADDR   003EH   A   
DLY_LP . . . . . .  C ADDR   0042H   A   
MAIN . . . . . . .  C ADDR   0030H   A   
MAIN_LP. . . . . .  C ADDR   0035H   A   
P0 . . . . . . . .  D ADDR   0080H   A   


REGISTER BANK(S) USED: 0 


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