Using a reed switch with Arduino

Forum 2005-2010 (read only) General Frequently-Asked Questions
18

Were I in your shoes, I'd try something very simple...

#define LED 13 //pin for the LED indicator (green)
#define PULSESWITCH 7 //pin for the switch

int val=0;
           
void setup()
{
  pinMode(LED,OUTPUT);
  pinMode(PULSESWITCH,INPUT);
}

void loop()
{
  val=digitalRead(PULSESWITCH);

  if (val==HIGH)
  {
    digitalWrite(LED, HIGH);
  }
}

If the LED lights, you know the digital input went high at some point. Then I'd do this...

#define LED 13 //pin for the LED indicator (green)
#define PULSESWITCH 7 //pin for the switch

int val=0;
           
void setup()
{
  pinMode(LED,OUTPUT);
  pinMode(PULSESWITCH,INPUT);
}

void loop()
{
  val=digitalRead(PULSESWITCH);

  if (val==LOW)
  {
    digitalWrite(LED, HIGH);
  }
}

If the LED lights, you know the digital input went low at some point. If the first two Sketches work, it is very likely the hardware is correct and I'd move on to the software.