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/*
   Reddit stepperPosition sketch revision #3
   12/5/2018
   Light sensor unknown? What kind of light sensor are you using, and how is it connected? 
*/

#include <Stepper.h>
#define STEPS 2038 // steps in one revolution (RPM) (28BYJ-48)
Stepper stepper(STEPS, 8, 10, 9, 11); // stepper digital pins on arduino


const int analogInPin = A0; // <---------------------------------------------------------------- Are you using the sensor's output on A0, or A5?
// --------------------------------------------------------------------------------------------- In line #60 you are reading pin A5? 


const int analogOutPin = 8; // <-------------------------------------------------- what is this pin doing?

int sensorValue = 0;
int pwmValue; // setting to an integer
int stepperPos = 4076;

// This version allows the stepper to turn eight rotations either direction from the initial starting position.
long minimum_stepper_position = -16304; // This is eight turns 'below' zero.
long maximum_stepper_position = 16304; // This is eight turns 'above' zero.

void setup() {
  // Setting pins for startup lights
  Serial.begin(9600);// Starts serial data transfer at 9600bps

  pinMode(3, OUTPUT); //Photosensor

  Serial.println("exiting setup()");
}


void loop() {

  check_light_sensor();

  if (sensorValue < 100) {
    rotate_stepper_motor_negative();
  }

  // Note: now there is a dead spot from 100 to 150.

  if (sensorValue > 150) {
    rotate_stepper_motor_positive();
  }

  delay(1000);
}


void check_light_sensor() {

  //Serial.print("\n"); <------------------------------------------------ this is incorrect, you need single quotes to print a character, not double quotes


  sensorValue = analogRead(A5); // read input of analog pin 5  ??????????  why are you reading pin A5 here? where is the sensor's output connected to?

  
  pwmValue = map(sensorValue, 0, 1023, 0, 255);
  Serial.print("PWMValue: ");
  Serial.println(pwmValue); //print PWMValue (0 to 255) to serial
}


void rotate_stepper_motor_negative() {
  // This function turns the motor up to 2 rotations negative, unless the lower-end limit has been reached.
  // If the motor is already at the lower end, then it won't try to turn any more in that direction.

  Serial.print("rotate negative");

  //show_stepper_start_position();
  //Serial.print("Night time value: ");
  //Serial.println(sensorValue);//print value read to the debug screen
  /*
    stepper.setSpeed(16); // 16 rpm
    int stepCounter = 0;
    int stepTarget = 4076;
    while (stepCounter < stepTarget) { // This condition limits movement to 2 rotations at the most.
    stepCounter = stepCounter + 1;
    if (stepperPos > minimum_stepper_position) { // This condition limits movement if the bottom end has been reached.
      stepperPos = stepperPos - 1;
      stepper.step(-1);
    }
    }
  */
  //show_stepper_end_position();
}


void rotate_stepper_motor_positive() {
  // This function turns the motor up to 2 rotations positive, unless the upper-end limit has been reached.
  // If the motor is already at the upper end, then it won't try to turn any more in that direction.

  Serial.print("rotate positive");

  //show_stepper_start_position();
  //Serial.print("Day time value: ");
  //Serial.println(sensorValue);//print value read to the debug screen
  /*
    stepper.setSpeed(16); // 16 rpm
    int stepCounter = 0;
    int stepTarget = 4076;
    while (stepCounter < stepTarget) { // This condition limits movement to 2 rotations at the most.
      stepCounter = stepCounter + 1;
      if (stepperPos < maximum_stepper_position) { // This condition limits movement if the top end has been reached.
        stepperPos = stepperPos + 1;
        stepper.step(1);
      }
    }
  */
  //show_stepper_end_position();
}


void show_stepper_start_position() {
  Serial.print("Current stepper position(START): ");
  Serial.println(stepperPos);
}


void show_stepper_end_position() {

  //Serial.print("\n"); <------------------------------------------------ this is incorrect, you need single quotes to print a character, not double quotes

  Serial.print("Current stepper position (END): ");
  Serial.println(stepperPos);
}