Arduino UNO 学习 （四） 8x8点阵、LCD1602液晶、DHT11温湿度传感器、74HC595位移缓存器

（一） 8x8点阵

代码

int LedPins[8] = {2, 7, 19, 5, 13, 18, 12, 16};
int GndPins[8] = {6, 11, 10, 3, 17, 4, 8, 9};

void setup() {
  // put your setup code here, to run once:
  for(int i = 0; i < 8; i++){
    pinMode(LedPins[i], OUTPUT);
    pinMode(GndPins[i], OUTPUT);
    digitalWrite(GndPins[i], HIGH);
  }
}
void LedOpen(){
  for(int i = 0; i < 8; i++){
    digitalWrite(LedPins[i], HIGH);
    digitalWrite(GndPins[i], LOW);
  }
  LedClose();
}
void LedClose(){
  for(int i = 0; i < 8; i++){
    digitalWrite(LedPins[i], LOW);
    digitalWrite(GndPins[i], HIGH);
  }
}
void LedCol(){
  for(int i = 0; i < 8; i++){
    digitalWrite(GndPins[i], LOW);
    for(int j = 0; j < 8; j++){
      digitalWrite(LedPins[j], HIGH);
      delay(40);
    }
    digitalWrite(GndPins[i], HIGH);
    LedClose();
  }
}
void LedRow(){
  for(int i = 0; i < 8; i++){
    digitalWrite(LedPins[i], HIGH);
    for(int j = 0; j < 8; j++){
      digitalWrite(GndPins[j], LOW);
      delay(40);
    }
    digitalWrite(LedPins[i], LOW);
    LedClose();
  }
}
void loop() {
  // put your main code here, to run repeatedly:
  LedOpen();
  delay(500);
  LedClose();
  delay(500);
  LedCol();
  delay(500);
  LedRow();
}

（二） LCD1602液晶

代码

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
void setup() {
  // put your setup code here, to run once:
  lcd.begin(16, 2);
  lcd.print("Hello He Ze !");
}

void loop() {
  // put your main code here, to run repeatedly:
  lcd.setCursor(0, 1);
  lcd.print(millis()/1000);
  lcd.print(" Second");
}

（三） DHT11温湿度传感器

#include <dht11.h>

dht11 DHT;
#define DHT11_PIN 4

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  Serial.println("DHT test program");
  Serial.print("Library vesion: ");
  Serial.println(DHT11LIB_VERSION);
  Serial.println();
  Serial.println("Type, 	status, 	Humidity (%), 	Temperature (C)");
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.print("DHT11, 	");
  int chk = DHT.read(DHT11_PIN);
  Serial.println(chk);
  switch (chk){
    case DHTLIB_OK: Serial.print("OK, 	"); break;
    case DHTLIB_ERROR_CHECKSUM: Serial.print("Checksum error, 	"); break;
    case DHTLIB_ERROR_TIMEOUT: Serial.print("Time out error, 	"); break;
    default: Serial.print("Unknow error, 	"); break;
  }
  Serial.print(DHT.humidity, 1);
  Serial.print(", 	");
  Serial.println(DHT.temperature, 1);
  delay(1000);
}

 

（四） 74HC595位移缓存器

代码

int latchpin = 10;
int clockpin = 9;
int datapin = 8;

void setup() {
  // put your setup code here, to run once:
  pinMode(latchpin, OUTPUT);
  pinMode(clockpin, OUTPUT);
  pinMode(datapin, OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
  for(int data = 0; data < 255; data++){
    digitalWrite(latchpin, LOW);
    shiftOut(datapin, clockpin, LSBFIRST, data);
    digitalWrite(latchpin, HIGH);
    delay(500);
  }
}

总结：

（1）DHT11温湿度传感器读到的信号，会报错，但是还是有温湿度的变化，不知怎么回事。

（2）模拟输入端A0-A5可以作为I/O口，编号为14-19；

（3）arduino基础的24个入门小实验，做完了，对arduino有了一定的初步认识。

　　  在理解传感器内部的电路的同时，要注意代码的逻辑，和硬件的连接，这类小实验还是很简单的。

（4）下次打算做arduino的一个开源项目，meArm机械臂，希望能对arduino开发板认识更深刻。