plx-daq

Using Arduino Interfacing w/ Software on the Computer
2

Hi Johan,

Define a state machine that switches between two states DISCONNECTED and CONNECTED depending on the signal from the button. Check the code below and you will see that it will only read once.

(partial code)

#define DISCONNECTED  0
#define CONNECTED  1

int state = DISCONNECTED;
bool makeMeasurement = false;

void setup()
{
  ...
}

void loop()
{

  // HANDLE STATEMACHINE
  int B = analogRead(buttonPin);  // assume LOW if pressed 
  if (state == DISCONNECTED && B == LOW)
  {
    state = CONNECTED;
    makeMeasurement = true;
  } 
  else 
  if (state == CONNECTED && B == HIGH)
  {
    state = DISCONNECTED;
  }

  // HANDLE MEASUREMENT
  if (makeMeasurement)
  {
    makeMeasurement = false; 
     int z = analogRead(A0);
     Serial.println(z);
  }
}

as said not tested but you should get it,

succes