How to use state machine in loop function?

[ignorantprogrammer]

I am making a program with a state machine. im using pir sensor and led. here is one of the lines of code:
if (currentState == 2 || currentState == 3) processPirState(currentState);

it should call this function when current state is either 2 or 3:

void processPirState(int currentState)
{

if(currentState == 2)
{
pirStat == digitalRead(pirPin);
if (pirStat == HIGH)
{
digitalWrite(ledPin, 1);
}
if (pirStat == LOW)
{
digitalWrite(ledPin, 0);
}
}

else if(currentState == 3)
{
digitalWrite(ledPin, 0);
}

}

however running the program and giving it 2 and 3 doesnt do anything in regards to the pir sensor. i feel like this is because it only gets called once as opposed to a loop, so it does indeed run but doesnt keep running therefore doesnt activate the pirsensor for more than 1 ms? please help, how would i go about solving this?

[UKHeliBob]

If you put your test and function call in loop() then it will be called each time through loop() if the condition is true. Is that not you want ?

Please post a complete sketch showing what you are doing and explaining how you want it to work

[Koepel]

You could upgrade your sketch to a Finite State Machine that we are used to.
Tutorial: https://hackingmajenkoblog.wordpress.com/2016/02/01/the-finite-state-machine/.
My own example: millis_and_finite_state_machine.ino

[gcjr]

@ignorantprogrammer

pirStat == digitalRead(pirPin);

perhaps you meant

pirStat = digitalRead(pirPin);

but why not simply

void
processPirState (
    int currentState )
{
    switch (currentState)  {
    case 2:
        digitalWrite (ledPin, digitalRead (pirPin));
        break;

    case 3:
        digitalWrite (ledPin, 0);
        break;
    }
}

[johnwasser]

void loop()
{
  switch (currentState)
  {
    case 2:
      pirStat = digitalRead(pirPin);  // note: fixed '==' error
      digitalWrite(ledPin, pirStat);
      break;

    case 3:
      digitalWrite(ledPin, LOW);
      break;
  }
}