Geeetech

Code: Select all

//RS485 has a enable/disable pin to transmit or receive data. 
//Arduino Digital Pin 2 = Rx/Tx 'Enable'; High to Transmit, Low to Receive
int EN = 2; 
 
void setup() 
{
  pinMode(EN, OUTPUT);
  Serial.begin(19200);
} 
 
void loop()
{
// send data 
  digitalWrite(EN, HIGH);//Enable data transmit
  Serial.print('A');
  delay(1000);
}

Code: Select all

int ledPin = 13;// Light up Led when receiving data
int EN = 2;
int val;
 
void setup() 
{
  pinMode(ledPin, OUTPUT);
  pinMode(EN, OUTPUT);
  Serial.begin(19200);
}
 
void loop()
{
  // receive data
 digitalWrite(EN, LOW);//Enable Receiving Data
 val = Serial.read();
  if (-1 != val) {
    if ('A' == val) {
      digitalWrite(ledPin, HIGH);
      delay(500);
      digitalWrite(ledPin, LOW);
      delay(500);
    }
 }
}