[Solved] Bench with counting capabilities

Projects General Guidance
14

I would be more comfortable if you made up your mind how many sensors you have and put that in the code. For example:

int ldr_pins[] = {  A0, A1, A2, A3, A4, A5, A6, A7, A8, A9};   // 10 pins
int now[] = {  0,0,0,0,0,0,0,0,0};   // 9 pins

So make it explicit:

const byte numberOfSensors = 10;

int ldr_pins[numberOfSensors] = {  A0, A1, A2, A3, A4, A5, A6, A7, A8, A9};   
int now[numberOfSensors] = {  0,0,0,0,0,0,0,0,0, 0};

Then:

 for (int i = 0; i < numberOfSensors; i++) {
    now[i] = analogRead(ldr_pins[i]);
    Serial.print ("now [i] = ");
    Serial.println (now [i]);    // debugging
    if (now[i] < then[i] - THRESH) {
      flag = true;
      Serial.println ("flag is true");  // more debugging
    }
    then[i] = now[i];
  }

Then add some debugging prints as shown and review the results.