PiRadio Arduino code for Power button and Relay Enable.txt

// RasPi Radio Power Button for Relay
// Made by Patrick Clark
// License: CC-BY-SA 3.0

// I used a Adafruit Trinket Arduino compatible board for this, 
// you can use any Arduino compatible board you prefer so long 
// as it has at least 2 Digital pins and 1 Analog pin.

const int buttonPin = 2;     // Power "ON" signal from Green pushbutton
const int RELAYpin = 1;     // 5V relay control pin
int Pival = 0;

unsigned long interval = 60000;   //60000 = 60 seconds - How long to keep Relay output HIGH
unsigned long startTime;
byte lastPress;

void setup() 
{                
  pinMode(buttonPin, INPUT);   // Set buttonPin as a digital input
  pinMode(RELAYpin, OUTPUT);  // Set Relaypin as a digital output
}
//
void loop() {
Pival = analogRead(2);  //  Read the analog voltage on Trinket Pin #4 (which is Analog2) from GPIO25 on Pi

 if (Pival > 450)       //  IF the Analog input has 3.3V from GPIO25 (Pi is booted) then keep relays enabled
 {
  digitalWrite(RELAYpin, HIGH);    //  Turn 5V Relay ON
 }

 else {             //  Otherwise, run the loop that watches for the Green button to be pressed
  
 
{
 byte pressed = digitalRead(buttonPin);
 if (pressed)
 {
   if (pressed != lastPress)
   {
  digitalWrite(RELAYpin, HIGH);   //  Turn 5V Relay ON
     startTime = millis();
   }
 }
 lastPress = pressed;
 if (digitalRead(RELAYpin))
 {
   if (millis() - startTime >= interval)   //  IF time interval (Pi boot time) has elapsed...
   {
     digitalWrite(RELAYpin, LOW);   //  Turn 5V Relay OFF (don't worry, if Pi has booted, it will keep relay Enabled)
   }
 }
}
}
}