ex4-8.lst

这个范例说明如何使用8051 的Port 1连接到四颗七段显示器

C51 COMPILER V8.05a   EX4_8                                                                08/25/2008 10:41:22 PAGE 1   


C51 COMPILER V8.05a, COMPILATION OF MODULE EX4_8
OBJECT MODULE PLACED IN ex4-8.OBJ
COMPILER INVOKED BY: d:\Keil\C51\BIN\C51.EXE ex4-8.c BROWSE DEBUG OBJECTEXTEND

line level    source

   1          /*
   2          标题：范例 4-8
   3          版本：1.0
   4          Target：89S51
   5          程序描述：这个范例说明如何使用8051 的Port 1连接到四颗七段显示器，PORT 0的低4位分别控制这四颗共阳七段显示器
             -，让四颗共阳七段显示器使用扫描的方式轮流
   6          显示数字。
   7                     这四颗七段显示器将显示0到 9999。 */
   8          /* ***************************************************** */
   9          #include <REGX51.H>
  10          #define TIMER0_COUNT 0xFC18 /* 10000h-(12,000,000/(12*1000)) */
  11          code 
  12          seven_seg[10]={0XC0,0XF9,0XA4,0XB0,0X99,0X92,0X82,0XF8,0X80,
  13          0X90};
  14          code scan[4]={0X0E,0X0D,0X0B,0X07};
  15          unsigned char counter[4]={0,0,0,0};
  16          unsigned char i=0;
  17          int timer0_tick;
  18          static void timer0_isr(void) interrupt TF0_VECTOR using 1
  19          {
  20   1        TR0=0;
  21   1        TL0=(TIMER0_COUNT & 0x00FF);
  22   1        TH0=(TIMER0_COUNT >> 8);
  23   1        TR0=1;
  24   1        P1=seven_seg[counter[i]];
  25   1        P0=scan[i];
  26   1        i++;
  27   1        if(i==4) i=0;
  28   1        timer0_tick++;
  29   1        if (timer0_tick==1000) {
  30   2            timer0_tick=0;
  31   2               counter[0]++;            // 个位数加1
  32   2               if (counter[0]==10) {    // 如果个位数等于10，则执行以下的部分
  33   3                     counter[0]=0;      // 个位数变成0
  34   3                     counter[1]++;      // 十位数加1
  35   3                     if(counter[1]==10){ // 如果十位数等于10，则执行以下的部分
  36   4                         counter[1]=0;  // 十位数变成0
  37   4                         counter[2]++;  // 百位数加1
  38   4                         if(counter[2]==10) { // 如果百位数等于10，则执行
  39   5                                                 以下的部分
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xD2 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xD4 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xCF skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xC2 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xB5 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xC4 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xB2 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xBF skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xB7 skipped
*** ERROR C100 IN LINE 39 OF EX4-8.C: unprintable character 0xD6 skipped
  40   5                         counter[2]=0;      // 百位数变成0
  41   5                           counter[3]++;   // 千位数加1
*** ERROR C187 IN LINE 41 OF EX4-8.C: not an lvalue
  42   5                           if(counter[3]==10) counter[3]=0; 
  43   5                                             //如果千位数等于10，则变成0
C51 COMPILER V8.05a   EX4_8                                                                08/25/2008 10:41:22 PAGE 2   

  44   5                         }
  45   4                      }
  46   3                 }
  47   2        }
  48   1      }
  49          static void timer0_initialize(void)
  50          {
  51   1        EA=0;
  52   1        timer0_tick=0;
  53   1        TR0=0;
  54   1        TMOD &= 0XF0;
  55   1        TMOD |=0x01;
  56   1        TL0=(TIMER0_COUNT & 0x00FF);
  57   1        TH0=(TIMER0_COUNT >> 8);
  58   1        PT0=0;
  59   1        ET0=1;
  60   1        TR0=1;
  61   1        EA=1;
  62   1      }
  63          void main (void)  {
  64   1        timer0_initialize();
  65   1        while (1);                        /* 无穷循环 */
  66   1      }
  67          

C51 COMPILATION COMPLETE.  0 WARNING(S),  11 ERROR(S)