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[Reply #15 on:]

when the PIR throws HIGH the LED strobes.  When the PIR throws LOW it fades while strobing repeatedly

[Reply #16 on:]

when the PIR throws HIGH the LED strobes.  When the PIR throws LOW it fades while strobing repeatedly

Not sure what you mean by "strobes". If the fading is not smooth, there is a problem with your LED or how it is wired.

[Reply #17 on:]

I messed with my hardware a bit and It was my LED going bad... Now the LED stays solid when the PIR throws HIGH and fades (as it should) but now it cycles through the fade when the PIR throws LOW

[Reply #18 on:]

Now the LED stays solid when the PIR throws HIGH and fades (as it should) but now it cycles through the fade when the PIR throws LOW

Have you changed the code so that firstLEDvalue has different values when the PIR throws HIGH and when it throws LOW? If not, then the behavior you are seeing is expected.

[Reply #19 on:]

Thanks for the help so far but I still haven't found a solution to this...

[Reply #20 on:]

Sketch?

[Reply #21 on:]

I finally figured it out! 

Code:

const int firstLED = 3;      // pin for the LED
const int inputPin = 2;      // input pin for the PIR sensor
int PIRstate;               // variable to hold the last PIR state
int val;                    // variable for reading the pin status

void setup() {

  pinMode(inputPin, INPUT);              //declare PIR as input
  PIRstate = digitalRead(inputPin);      //assign PIR state to PIRstate
}

void loop() {

  val = digitalRead(inputPin);      // read input value
  if (val != PIRstate)                      // check if the input has changed
  {
    if(val == HIGH){ 
      analogWrite(firstLED, 255);
    }
    else{

      for(int fadeValue = 255 ; fadeValue >= 0; fadeValue -=5) {
        // sets the value (range from 0 to 255):
        analogWrite(firstLED, fadeValue);         
        // wait for 30 milliseconds to see the dimming effect   
        delay(30);                           
      }
    }
  }
  PIRstate = val;                 // save the new state to the variable
}