超声波测距数码管显示

之前学习了超声波测距，然后学习了点亮数码管，此例使用数码管显示测得的距离

//4位8段共阴数码管引脚图
//1 a f 2 3 b
//e d dp c g 4

//abcdefg. 分别是8段引脚
int a = 9;
int b =13;
int c = A2;
int d = A4;
int e = A5;
int f = 10;
int g = 3;
int dp = A3;

//“1 2 3 4”是对应数码管
int d1 = 8;
int d2 = 11;
int d3 = 12;
int d4 = 4;

//超声波模块
int TrgPin = A0;
int EcoPin = A1;
int dist;

void setup() {
  // put your setup code here, to run once:
  pinMode(a, OUTPUT);//设置为输出
  pinMode(b, OUTPUT);
  pinMode(c, OUTPUT);
  pinMode(d, OUTPUT);
  pinMode(e, OUTPUT);
  pinMode(f, OUTPUT);
  pinMode(g, OUTPUT);
  pinMode(dp, OUTPUT);
  pinMode(d1, OUTPUT);
  pinMode(d2, OUTPUT);
  pinMode(d3, OUTPUT);
  pinMode(d4, OUTPUT);

  Serial.begin(9600);//串口通信波特率
//设置TrgPin为输出状态
pinMode(TrgPin, OUTPUT);
// 设置EcoPin为输入状态
pinMode(EcoPin, INPUT);
}


void loop() {
    digitalWrite(TrgPin, LOW);
    delayMicroseconds(10);
    // 维持10毫秒高电平用来产生一个脉冲
    digitalWrite(TrgPin, HIGH);
    delayMicroseconds(10);
    digitalWrite(TrgPin, LOW);
    // 读取脉冲的宽度并换算成距离
    
    dist = pulseIn(EcoPin, HIGH) / 58;//实际距离就是1厘米对应58微秒。
    if (dist > 0)//排除0距离的问题
    {
    Serial.print("Distance:");//输出到串口
    Serial.print(dist);
    Serial.println("cm");

    Display(1, dist % 10000 / 1000);//提取万位数数字，其实这个用不到，毕竟探测最多300cm
    Display(2, dist % 1000 / 100);
    Display(3, dist % 100 / 10);
    Display(4, dist % 10 / 1);//提取个位数数字
    }}

//x为第几个数码管， Number为数字
void Display(unsigned char x, unsigned char Number)
{
  SetPosition(x);
  SetNumber(Number);
  delay(1);
  Clear();
}

//1-2-3-4确定选择哪个位置数码管，拉低选中对应数码管
void SetPosition(unsigned char n)
{
  switch(n)
  {
    case 1:
      digitalWrite(d1, LOW);
      digitalWrite(d2, HIGH);
      digitalWrite(d3, HIGH);
      digitalWrite(d4, HIGH);
      break;
    case 2:
      digitalWrite(d1, HIGH);
      digitalWrite(d2, LOW);
      digitalWrite(d3, HIGH);
      digitalWrite(d4, HIGH);
      break;
    case 3:
      digitalWrite(d1, HIGH);
      digitalWrite(d2, HIGH);
      digitalWrite(d3, LOW);
      digitalWrite(d4, HIGH);
      break;
    case 4:
      digitalWrite(d1, HIGH);
      digitalWrite(d2, HIGH);
      digitalWrite(d3, HIGH);
      digitalWrite(d4, LOW);
      break;
    default:
      digitalWrite(d1, HIGH);
      digitalWrite(d2, HIGH);
      digitalWrite(d3, HIGH);
      digitalWrite(d4, HIGH);
      break;
  }
}

//选择要显示的数字
void SetNumber(unsigned char n)
{
  switch(n)
  {
    case 0:
      Num_0();
      break;
    case 1:
      Num_1();
      break;
    case 2:
      Num_2();
      break;
    case 3:
      Num_3();
      break;
    case 4:
      Num_4();
      break;
    case 5:
      Num_5();
      break;
    case 6:
      Num_6();
      break;
    case 7:
      Num_7();
      break;
    case 8:
      Num_8();
      break;
    case 9:
      Num_9();
      break;
    default:
      Clear();
      break;
  }
}

//清屏
void Clear()
{
  digitalWrite(a, LOW);
  digitalWrite(b, LOW);
  digitalWrite(c, LOW);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
  digitalWrite(dp, LOW);
}

//设置每个数字的显示所需要点亮的部分
void Num_0()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, LOW);
  digitalWrite(dp, LOW);
}

void Num_1()
{  
  digitalWrite(a, LOW);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
  digitalWrite(dp, LOW);
}
void Num_2()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, LOW);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, LOW);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_3()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_4()
{  
  digitalWrite(a, LOW);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_5()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_6()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, LOW);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_7()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, LOW);
  digitalWrite(e, LOW);
  digitalWrite(f, LOW);
  digitalWrite(g, LOW);
  digitalWrite(dp, LOW);
}

void Num_8()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, HIGH);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}

void Num_9()
{  
  digitalWrite(a, HIGH);
  digitalWrite(b, HIGH);
  digitalWrite(c, HIGH);
  digitalWrite(d, HIGH);
  digitalWrite(e, LOW);
  digitalWrite(f, HIGH);
  digitalWrite(g, HIGH);
  digitalWrite(dp, LOW);
}