Flashing Lights for Keyless Entry

Other Hardware LEDs and Multiplexing
1

Hello everyone! I am new to the forum but I have a question that some of you may be able to answer.

I recently installed a keyless entry/central locking module in my car and it works great but there is no function to make the lights flash when I lock and unlock the car. I am trying to use an Arduino UNO to make the lights flash once when I press the lock button on the key fob and flash twice when I press the unlock button on the key fob. I want the code to run once per button push regardless the interval of time the input pin receives the signal for and then return to waiting for another input.

The problem I am having with my program is that it will begin making the lights flash without any input going to the input pins. Any help is appreciated! Thank you.

Power_Locks_Flash.ino (933 Bytes)

2

Please post your code as shown in the forum guide, along with links to components and your schematic diagram.

3

This is my code so far.

int lock = 2;
int unlock = 4;
int flashOnce = 12;
int flashTwice = 8;

void setup()
{
pinMode(12, OUTPUT);
pinMode(8, OUTPUT);
pinMode(2, INPUT);
pinMode(4, INPUT);
}

void loop() 
{
  if(digitalRead(lock) == HIGH)
    {
    lockprocedure();
    }
  if(digitalRead(unlock) == HIGH)
    {
    unlockprocedure();
    }

}
void lockprocedure()
{
   digitalWrite(flashOnce, HIGH);
   delay(450);
   digitalWrite(flashOnce, LOW);
   delay(250);
}
void unlockprocedure()
{
    digitalWrite(flashTwice, HIGH);
    delay(375);
    digitalWrite(flashTwice, LOW);
    delay(250);
    digitalWrite(flashTwice, HIGH);
    delay(375);
    digitalWrite(flashTwice, LOW);
    delay(250);
}
4

At this point I would guess that your inputs are floating. You could try using INPUT_PULLUP instead of INPUT in the pinMode() calls. But until you post those links and schematic, that's just a guess.

5

I just want either "lockprocedure" or "unlockprocedure" to run when either the "lock" pin or "unlock" pin receives a HIGH regardless of the amount of time that it receives the signal for. What is happening is that "lockprocedure" and "unlockprocedure" continually run without an input into either "lock" pin or "unlock" pin.

I know how it should be wired, but I am just unsure about how to do the coding.

6

Enozoi:
I know how it should be wired

At this point, I don't believe you. Please prove me wrong. What about the suggestions in post #3?

7

Got it to work lol.

8

How did you get it to work? Others with similar problems may be searching the forum now or in the future. Let them know how you fixed it.

9

I had to add in quite a few more things so that the input would not "float" and I added a pull-down resistor into the wiring. Thanks for the help.

const int lock = 2; //naming each pin
const int unlock = 4;
const int flashOnce = 12;
const int flashTwice = 8;
int buttonState = 0;
int buttonState2 = 0;
int lastButtonState = 0;
int lastButtonState2 = 0;

void setup() 
{
pinMode(lock, INPUT);
pinMode(unlock, INPUT); //setting input and output pins
pinMode(flashOnce, OUTPUT);
pinMode(flashTwice, OUTPUT);
}

void loop() 
{
  buttonState = digitalRead(lock);
  buttonState2 = digitalRead(unlock);
    if(buttonState != lastButtonState)
    {
      if(buttonState == HIGH) //when lock button is pushed on keyfob, lights will flash once
      {
        lockprocedure();
      }
     delay(50); 
    }  
  lastButtonState = buttonState;
    if(buttonState2 != lastButtonState2)
    {
      if(buttonState2 == HIGH) //when unlock button is pressed on keyfob, lights will flash twice
      {
        unlockprocedure();
      }
     delay(50); 
    }  
  lastButtonState2 = buttonState2;  
}
void lockprocedure()
{
  digitalWrite(flashOnce, HIGH);
  delay(400);
  digitalWrite(flashOnce, LOW);
  delay(250);
}
void unlockprocedure()
{
  digitalWrite(flashTwice, HIGH);
  delay(625);
  digitalWrite(flashTwice, LOW);
  delay(500);
  digitalWrite(flashTwice, HIGH);
  delay(625);
  digitalWrite(flashTwice, LOW);
  delay(500);
}
10

Now all I have to do is go through the process of actually wiring this into the car, but at least I know that my code works now.

11

Nothing you added to your code has prevented the inputs from floating. The pull-down resistor will have done that. With no schematic, this thread is not going to help any other beginners in future.