Why is it saying 'buttonState' and 'rotateMotor' "was not declared in this scope"?

Projects Programming
1

I tried putting two codes together. One is for leds that if you press a button it switches to a different led bulb. The other is for my robot to follow humans. They worked fine alone, but when put together, I get errors. 'buttonState' was not declared in this scope. 'rotateMotor' was not declared in this scope.

#include <NewPing.h>

#define ULTRASONIC_SENSOR_TRIG 11
#define ULTRASONIC_SENSOR_ECHO 12

#define MAX_FORWARD_MOTOR_SPEED 75
#define MAX_MOTOR_TURN_SPEED_ADJUSTMENT 50

#define MIN_DISTANCE 10
#define MAX_DISTANCE 30

#define IR_SENSOR_RIGHT 2
#define IR_SENSOR_LEFT 3

#define LED_1_PIN 5
#define LED_2_PIN 10
#define LED_3_PIN 9
#define BUTTON_PIN 4

#define LED_NUMBER 3

byte LEDPinArray[LED_NUMBER] = { LED_1_PIN,
                                 LED_2_PIN,
                                 LED_3_PIN };

unsigned long debounceDuration = 50; // millis
unsigned long lastTimeButtonStateChanged = 0;

byte lastButtonState = HIGH;

int LEDIndex = 0;

void initAllLEDs()
{
  for (int i = 0; i < LED_NUMBER; i++) {
    pinMode(LEDPinArray[i], OUTPUT);
  }
}

void powerOnSelectedLEDOnly(int index)
{
  for (int i = 0; i < LED_NUMBER; i++) {
    if (i == index) {
      digitalWrite(LEDPinArray[i], HIGH);
    }
    else {
      digitalWrite(LEDPinArray[i], LOW);
    }
  }
}

//motor code starts here

//Right motor
int enableRightMotor=5;
int rightMotorPin1=7;
int rightMotorPin2=8;

//Left motor
int enableLeftMotor=6;
int leftMotorPin1=9;
int leftMotorPin2=10;

NewPing mySensor(ULTRASONIC_SENSOR_TRIG, ULTRASONIC_SENSOR_ECHO, 400);

void setup()
{
  // put your setup code here, to run once:
  pinMode(enableRightMotor, OUTPUT);
  pinMode(rightMotorPin1, OUTPUT);
  pinMode(rightMotorPin2, OUTPUT);
  
  pinMode(enableLeftMotor, OUTPUT);
  pinMode(leftMotorPin1, OUTPUT);
  pinMode(leftMotorPin2, OUTPUT);

  pinMode(IR_SENSOR_RIGHT, INPUT);
  pinMode(IR_SENSOR_LEFT, INPUT);
  rotateMotor(0,0);   
  
//led setup here
    initAllLEDs(); 
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  digitalWrite(LEDPinArray[LEDIndex], HIGH);
}


void loop()
{
  int distance = mySensor.ping_cm();
  int rightIRSensorValue = digitalRead(IR_SENSOR_RIGHT);
  int leftIRSensorValue = digitalRead(IR_SENSOR_LEFT);

  //led loop code here

    unsigned long timeNow = millis();
  if (timeNow - lastTimeButtonStateChanged > debounceDuration) {
      byte buttonState = digitalRead(BUTTON_PIN); }
    if (buttonState != lastButtonState) {
      lastTimeButtonStateChanged = timeNow;
      lastButtonState = buttonState; }
      if (buttonState == HIGH) { // button has been released
        LEDIndex++; 
        if (LEDIndex >= LED_NUMBER) {
          LEDIndex = 0;
        }
        powerOnSelectedLEDOnly(LEDIndex);
      }

  //NOTE: If IR sensor detects the hand then its value will be LOW else the value will be HIGH
  
  //If right sensor detects hand, then turn right. We increase left motor speed and decrease the right motor speed to turn towards right
  if (rightIRSensorValue == LOW && leftIRSensorValue == HIGH )
  {
      rotateMotor(MAX_FORWARD_MOTOR_SPEED - MAX_MOTOR_TURN_SPEED_ADJUSTMENT, MAX_FORWARD_MOTOR_SPEED + MAX_MOTOR_TURN_SPEED_ADJUSTMENT ); 
  }
  //If left sensor detects hand, then turn left. We increase right motor speed and decrease the left motor speed to turn towards left
  else if (rightIRSensorValue == HIGH && leftIRSensorValue == LOW )
  {
      rotateMotor(MAX_FORWARD_MOTOR_SPEED + MAX_MOTOR_TURN_SPEED_ADJUSTMENT, MAX_FORWARD_MOTOR_SPEED - MAX_MOTOR_TURN_SPEED_ADJUSTMENT); 
  }
  //If distance is between min and max then go straight
  else if (distance >= MIN_DISTANCE && distance <= MAX_DISTANCE)
  {
    rotateMotor(MAX_FORWARD_MOTOR_SPEED, MAX_FORWARD_MOTOR_SPEED);
  }
  //stop the motors
  else
  {
    rotateMotor(0, 0);
  }
}



void rotateMotor(int rightMotorSpeed, int leftMotorSpeed)
{
  if (rightMotorSpeed < 0)
  {
    digitalWrite(rightMotorPin1,LOW);
    digitalWrite(rightMotorPin2,HIGH);    
  }
  else if (rightMotorSpeed > 0)
  {
    digitalWrite(rightMotorPin1,HIGH);
    digitalWrite(rightMotorPin2,LOW);      
  }
  else
  {
    digitalWrite(rightMotorPin1,LOW);
    digitalWrite(rightMotorPin2,LOW);      
  }

  if (leftMotorSpeed < 0)
  {
    digitalWrite(leftMotorPin1,LOW);
    digitalWrite(leftMotorPin2,HIGH);    
  }
  else if (leftMotorSpeed > 0)
  {
    digitalWrite(leftMotorPin1,HIGH);
    digitalWrite(leftMotorPin2,LOW);      
  }
  else 
  {
    digitalWrite(leftMotorPin1,LOW);
    digitalWrite(leftMotorPin2,LOW);      
  }
  analogWrite(enableRightMotor, abs(rightMotorSpeed));
  analogWrite(enableLeftMotor, abs(leftMotorSpeed));    
}
2

Make buttonState variable a global variable.

BTW, google scope

3

This is because these variables are not declared anywhere.
Declare them just after the #defines at the start of the code.

4 
byte lastButtonState = HIGH;
byte buttonState;           // <<<<< Add this line