Nano->distance, Run DC motor, then blink led+sound, then dc motor reverse

Projects Programming
1

Hello people!

I'm into doing a halloween project, where I have a HC-SR04 distance sensor to activate this:
First dc motor (connected to L298N) should run for 2 second (sliding a curtain away)
Then a LED light should blink with strobe effect and a scream from sd card play for about 6 seconds (or as long as there is motion in HC-SR04 area)

My first code, with PIR motion sensor, and only strobe blink and scream sound is this and working for 6 seconds:

const byte led = 2;                 // LED pin
const byte sensor = 9;              // PIR sensor pin
bool isActivated = false;

#include "SoftwareSerial.h"
#include "DFRobotDFPlayerMini.h"

SoftwareSerial mySoftwareSerial(10, 11); // RX, TX
DFRobotDFPlayerMini myDFPlayer;

const unsigned long pauseTime = 6000;   // how long between PIR detections
const unsigned long blinkTime = 100;    // how fast to blink led

unsigned long startTime; // time PIR triggered
unsigned long lastTime; // last time we toggled led

void setup() {
  pinMode(led, OUTPUT);      // set led pin as output
  pinMode(sensor, INPUT);    // set sensor pin as input

  mySoftwareSerial.begin(9600);
  Serial.begin(115200);

  Serial.println(F("\nInitializing DFPlayer..."));

  //Use softwareSerial to communicate with MP3
  if (!myDFPlayer.begin(mySoftwareSerial)) {
    Serial.println(F("Unable to begin:"));
    Serial.println(F("1.Please recheck the connection!"));
    Serial.println(F("2.Please insert the SD card!"));
    while (true);
  }
  Serial.println(F("DFPlayer Mini online."));

  //Set volume value (From 0 to 30)
  myDFPlayer.volume(5);
}

void loop() {
  if ( isActivated ) {
    // blink led
    if ( millis() - lastTime >= blinkTime ) {
      lastTime = millis();
      digitalWrite(led, !digitalRead(led));
    }

    // check if we have been active long enough
    if ( millis() - startTime >= pauseTime ) {
      isActivated = false; // force PIR to trigger again or not
    }
  }

  if ( isActivated == false ) {
    // check PIR
    int pirSensor = digitalRead(sensor);
    if (pirSensor == HIGH) {
      isActivated = true;
      startTime = millis();
      Serial.println("Sensor Activated");
      Serial.println("DFPlayer Working...");
      myDFPlayer.play(1);
    }
  }
}

Now I want to replace the PIR sensor with a distance sensor, and add the dc motor to run before the blink led/scream sound, and then the dc motor run reverse after the blink/sound have played.

My dc motor code with distance sensor is this (just need to figure out to reverse the HIGH/LOW)

// controlling dc motor with ultrasonic sensor
int trig = 5;// Initialize pin D5 as HC-SR04 trigger pin
int echo = 4;// Initialize pin D5 as HC-SR04 Echo pin
int motorPin1 = 10; //Initialize pin D10 to drive motor1
int motorPin2 = 11;//Initialize pin D11 to drive motor1
int duration = 0;
int distance = 0;
void setup()
{
  pinMode(trig , OUTPUT);
  pinMode(echo , INPUT);
  pinMode(motorPin1 , OUTPUT);
  pinMode(motorPin2 , OUTPUT);
  Serial.begin(9600);

}

void loop() {
  digitalWrite(trig , HIGH);
  delayMicroseconds(1000);
  digitalWrite(trig , LOW);

  duration = pulseIn(echo , HIGH);
  distance = (duration / 2) / 28.5 ;// calculate distance in CM
  //Serial.println(distance);

  if ( distance < 20 ) {
    Serial.print(distance);

    digitalWrite(motorPin1, LOW);
    digitalWrite(motorPin2 , LOW);
    Serial.println("cm   MOTOR STOP");
    delay(1000);
  }
  else {
    Serial.print(distance);
    digitalWrite(motorPin1, HIGH);
    digitalWrite(motorPin2 , LOW);
    Serial.println("cm   MOTOR START");
    delay(1000);
  }
}

Any guidance to replace the PIR with distance sensor, and merge the dc motor into the first code?
Thank you!

Ps: My english is not so good, so all the "technical english" can be hard to understand, nut i'm trying :slight_smile:

2

Don't try to do them both at once. Maybe do the distance sensor first - you can use it to set the activated flag.

Eventually though, I suspect you will need to restructure your code as a state machine.

3

But how?
Should the “const byte sensor = 9; // PIR sensor pin”
Be the trigger pin on the distance sensor?