c - "Refreshing"8051微 Controller :

Question

void main(void)
{
 unsigned char in_char;
   int flag=1,j,i;
   int count, d = 0 ; 
   char s[4]="",p;
   ithul();
   LCD_res();
   init_lcd()
   ;print_lcd(1,"The Project");//Printing command.
   ;print_lcd(2,"of Me:");//Printing command.
   for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
   for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}

while(1)
  {
 count = 0;
    loop1 : if(P3_0 == 1){
      goto loop1;
      }
//Running '1' 
    loop2 : if(P3_0 == 0){
      goto loop2;
      }
//Running '0'
    while(P3_0 == 1){
      count ++;
       }
  init_lcd()
   ;print_lcd(1,"Done Counting!");//Printing command.
   for(i=0; i<1; i++){delay(1000);delay(1000);delay(1000);}

   ;print_lcd(2,"    - L/H...");//Printing command.
   for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
   for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
    for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}

   ;print_lcd(2,itoa(count/200));//Printing command.
   for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
    for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
   }
}

这是我的代码。它的作用是从端口获取频率，读取它并将其打印到 LCD。

它的作品!但大约 2 分钟后，液晶显示屏变得像“asda68!#123646$#$^%&*(dfas”一样的垃圾!。

如何刷新 8051 微 Controller 以免它变得疯狂？我听说过一些关于“新鲜”“免费”“闪存”命令的信息，但我真的不知道它是什么或如何使用它。所以..请帮忙!

Answer 1

你的功能:

char * itoa( int x ) { 
    const unsigned int BASE = 10; 
    unsigned int u = abs( x ); 
    size_t n = 0; 
    unsigned int tmp = u; 
    char *s; 
    do { ++n; } 
    while ( tmp /= BASE ); 
    n += x < 0; 
    s = malloc( ( n + 1 ) * sizeof( char ) ); 
    s[n] = 0; 
    do { s[--n] = u % BASE + '0'; } 
    while ( u /= BASE ); 
    if ( x < 0 ) s[--n] = '-'; 
    return s;
} 

每次调用 itoa() 时，它都会为字符串 s 分配更多内存，一段时间后它会耗尽内存但从不检查返回值来自malloc()。您需要将 free() 放回到程序中。

char *strg;
...
strg = itoa (count / 200);
print_lcd(2,strg);
free(strg);

所以整个代码看起来像这样，看看注释的地方。

void main(void) {
    char *strg;                 // new variable
    unsigned char in_char;
    int flag=1,j,i;
    int count, d = 0 ; 
    char s[4]="",p;
    ithul();
    LCD_res();
    init_lcd();
    print_lcd(1,"The Project");//Printing command.
    print_lcd(2,"of Me:");//Printing command.
    for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
    for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}

    while(1) {
        count = 0;
        loop1 : if(P3_0 == 1){
            goto loop1;
        }
        //Running '1' 
        loop2 : if(P3_0 == 0){
            goto loop2;
        }
        //Running '0'
        while(P3_0 == 1){
            count ++;
        }
        init_lcd();
        print_lcd(1,"Done Counting!");//Printing command.
        for(i=0; i<1; i++){delay(1000);delay(1000);delay(1000);}

        print_lcd(2,"    - L/H...");//Printing command.
        for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
        for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
        for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}

        strg = itoa (count / 200);  // keep the returned pointer
        print_lcd(2,strg);          // display the "frequency"
        free(strg);                 // free the pointer memory
        for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
        for(i=0; i<20; i++){delay(1000);delay(1000);delay(1000);}
    }
}