赤外線投光器を制御するArduinoスケッチ。20秒でタイムアウト。

gistfile1.ino

const int IRLED_PIN = 13;
const unsigned long IRLED_TIMEOUT = 20 * 1000; // ms

char buffer[16] = {0};
unsigned char buffer_counter = 0;
unsigned long irled_expire = 0;

void setup()
{
  pinMode(IRLED_PIN, OUTPUT);
  Serial.begin(9600);
  Serial.println("SETUP");
}

void parse_command(String command)
{
  if ( command.equals("IRLED") )
  {
    Serial.println(digitalRead(IRLED_PIN) == HIGH ? "IRLED:ON" : "IRLED:OFF");
  }
  else if ( command.equals("IRLED:ON") )
  {
    irled_expire = millis() + IRLED_TIMEOUT;
    digitalWrite(IRLED_PIN, HIGH);
    Serial.println("IRLED:ON");
  }
  else if ( command.equals("IRLED:OFF") )
  {
    digitalWrite(IRLED_PIN, LOW);
    Serial.println("IRLED:OFF");
  }
}

void read_serial()
{
  if ( Serial.available() > 0 )
  {
    buffer[buffer_counter] = (char)Serial.read();
    buffer_counter++;
    if ( buffer_counter >= sizeof(buffer) )
    {
      buffer_counter = 0;
    }
    if ( buffer[buffer_counter - 1] == '\n' )
    {
      buffer[buffer_counter - 1] = '\0';
      parse_command(String(buffer));
      buffer_counter = 0;
    }
  }
}

void irled_timeout()
{
  if ( millis() > irled_expire && digitalRead(IRLED_PIN) == HIGH )
  {
    digitalWrite(IRLED_PIN, LOW);
    Serial.println("IRLED:OFF");
  }
}

void loop()
{
  read_serial();
  irled_timeout();
}