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按键盘数码管流动显示实验

要求:按下键盘,六个数码管流动显示按下的值。

连线:将片选CS0接到key_LED_CS上

#include  <reg52.h>

#define   LEDLen   6

xdata unsigned char OUTBIT _at_ 0x8002;   // 位控制口

xdata unsigned char OUTSEG _at_ 0x8004;   // 段控制口

xdata unsigned char IN     _at_ 0x8001;   // 键盘读入口

unsigned char LEDBuf[LEDLen];    // 显示缓冲

code unsigned char LEDMAP[] = {  // 八段管显示码 (点不显示,0-F)

  0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7d, 0x07,

  0x7f, 0x6f, 0x77, 0x7c, 0x39, 0x5e, 0x79, 0x71

};

code unsigned char KeyTable[] = {   // 键码定义

  0x16, 0x15, 0x14, 0xff,

  0x13, 0x12, 0x11, 0x10,

  0x0d, 0x0c, 0x0b, 0x0a,

  0x0e, 0x03, 0x06, 0x09,

  0x0f, 0x02, 0x05, 0x08,

  0x00, 0x01, 0x04, 0x07

void Delay(unsigned char CNT)

{

  unsigned char i;

  while (CNT-- !=0)

    for (i=100; i !=0; i--);

}

void DisplayLED()

  unsigned char Pos;

  unsigned char LED;

  Pos = 0x20;       // 从左边开始显示

  for (i = 0; i < LEDLen; i++) {

    OUTBIT = 0;     // 关所有八段管

    LED = LEDBuf[i];

    OUTSEG = LED;

    OUTBIT = Pos;   // 显示一位八段管

    Delay(2);

    Pos >>= 1;      // 显示下一位

  }

unsigned char TestKey()

   OUTBIT = 0;            // 输出线置为0

   return (~IN & 0x0f);   // 读入键状态(高四位不用)

unsigned char GetKey()

  unsigned char k;

  i = 6;

  Pos = 0x20;     // 找出键所在列

  do {

    OUTBIT = ~ Pos;

    Pos >>= 1;

    k = ~IN & 0x0f;

  } while ((--i != 0) && (k == 0));

  // 键值 = 列 x 4 + 行

  if (k != 0)

  {

    i *= 4;

    if (k & 2)

      i += 1;

    else if (k & 4)

      i += 2;

    else if (k & 8)

      i += 3;

    OUTBIT = 0;

    do

      Delay(10); while (TestKey());  // 等键释放

    return(KeyTable[i]);  // 取出键码

  } else return(0xff);

void main()

{    unsigned int i=0;

   LEDBuf[0] = 0x00;  //如果设置为3F那么最初第一个数码管显示为0

   LEDBuf[1] = 0x00;

   LEDBuf[2] = 0x00;

   LEDBuf[3] = 0x00;

   LEDBuf[4] = 0x00;

   LEDBuf[5] = 0x00;

   while (1) {

     DisplayLED();

     if (TestKey())

     {

         LEDBuf[i++%6] = LEDMAP[GetKey() & 0x0f];

       //LEDBuf[5]=LEDMP[GetKey()&0x0f];

     }

   }

本文转自蓬莱仙羽51CTO博客,原文链接:http://blog.51cto.com/dingxiaowei/1366582,如需转载请自行联系原作者