外部口读写.lst

用keil c对绝对地址的访问

C51 COMPILER V8.02   外部口读写                                                            11/01/2000 22:26:55 PAGE 1   


C51 COMPILER V8.02, COMPILATION OF MODULE 外部口读写
OBJECT MODULE PLACED IN 外部口读写.OBJ
COMPILER INVOKED BY: D:\keil\C51\BIN\C51.EXE 外部口读写.c BROWSE DEBUG OBJECTEXTEND

line level    source

   1          #include <reg52.h>     //包括一个52标准内核的头文件
   2          #define uchar unsigned char //定义一下方便使用
   3          #define uint  unsigned int
   4          
   5          void Delay(uchar i)
   6          {
   7   1              uchar m;
   8   1              uchar n;
   9   1      
  10   1       for(m=0;m<i;m++)
  11   1       {
  12   2              for(n=0;n<255;n++)
  13   2              {
  14   3                      //_nop_;
  15   3              }
  16   2       }
  17   1      
  18   1      }
  19          
  20          
  21          main()
  22          {
  23   1              uchar xdata *Key_addr;             /*定义Key的地址*/
  24   1              uchar xdata *Led_addr;         /*定义led灯的地址指针*/
  25   1              Led_addr=0xf0;
  26   1              Key_addr=0x80;
  27   1      
  28   1              while(1)
  29   1              {
  30   2                      uchar key;
  31   2                      key=*Key_addr;                /*取键值*/
  32   2                  *Led_addr=key;                        /*显示键值*/
  33   2                      Delay(255);                               /*延时*/
  34   2                      *Led_addr=0x0f;           
  35   2                      Delay(255);
  36   2              *Led_addr=0xf0;   
  37   2                      Delay(255);
  38   2      
  39   2      
  40   2              }
  41   1      
  42   1      }


MODULE INFORMATION:   STATIC OVERLAYABLE
   CODE SIZE        =     60    ----
   CONSTANT SIZE    =   ----    ----
   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
   DATA SIZE        =   ----       3
   IDATA SIZE       =   ----    ----
   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  0 WARNING(S),  0 ERROR(S)