pwm1.lst

用单片机的可变pwm的输出实现正弦波的输出。

C51 COMPILER V8.02   PWM1                                                                  04/19/2007 22:34:29 PAGE 1   


C51 COMPILER V8.02, COMPILATION OF MODULE PWM1
OBJECT MODULE PLACED IN PWM1.OBJ
COMPILER INVOKED BY: C:\Keil\C51\BIN\C51.EXE PWM1.c BROWSE DEBUG OBJECTEXTEND

line level    source

   1           #include<reg51.h>              //2005.11.18 By ClimberWin
   2           #include<stdio.h>          //PWM调制
   3           #include<math.h>
   4           sbit   P32=P3^2;               //端口设置
   5           sbit   P33=P3^3;
   6           sbit   P10=P1^0;
   7           sbit   P17=P1^7;
   8           unsigned int j;                //设置全局变量用于控制延时时间
   9           void delay(unsigned int i)//**   //延时子程序
  10          {                                                  //**
  11   1       unsigned int n;                   //**
  12   1       n=0;                                      //**
  13   1       while(n < i)                      //**
  14   1       {n++;}                                    //**
  15   1       return;                                   //**
  16   1       }                                                 //**
  17           //****************************
  18           //主程序/
  19           void main(void)
  20          { 
  21   1        
  22   1         j=100; //赋初值,占空比为1/2
  23   1      loop: 
  24   1         if (P32==0)     //步进加
  25   1            {j=j+1;}           
  26   1         else
  27   1      
  28   1           if (P33==0)   //步进减
  29   1              {j=j-1;}
  30   1             else
  31   1           
  32   1        if (j<500) 
  33   1        { ;
  34   2         }
  35   1        else
  36   1        { j=250;
  37   2          }
  38   1        
  39   1              OutputPWM(); 
*** WARNING C206 IN LINE 39 OF PWM1.C: 'OutputPWM': missing function-prototype
  40   1              goto loop;      //循环
  41   1       }
  42            
  43           //**********************一个脉冲周期j是预赋值。一个周期不变，来改变占空比
  44           OutputPWM(void)   
  45           { 
  46   1         P10=!P10; 
  47   1         delay(500-j);
  48   1         P10=!P10;
  49   1         delay(j); 
  50   1        }
  51            //*********************


MODULE INFORMATION:   STATIC OVERLAYABLE
C51 COMPILER V8.02   PWM1                                                                  04/19/2007 22:34:29 PAGE 2   

   CODE SIZE        =     97    ----
   CONSTANT SIZE    =   ----    ----
   XDATA SIZE       =   ----    ----
   PDATA SIZE       =   ----    ----
   DATA SIZE        =      2    ----
   IDATA SIZE       =   ----    ----
   BIT SIZE         =   ----    ----
END OF MODULE INFORMATION.


C51 COMPILATION COMPLETE.  1 WARNING(S),  0 ERROR(S)