petfood.c

#include <Time.h>

int RFIDResetPin = 13;

//Register your RFID tags here
char tag1[13] = "84003378CA05";
char tag2[13] = "840033725D98";

char cat1name[5] = "Toby";
char cat2name[8] = "Biscuit";

int cat1last = 0;
int cat2last = 0;
int lastFeeding = 0;
int cat1amount = 0;
int cat2amount = 0;

int GLOBAL_DELAY = 15;
int FEED_DELAY = 30;

void setup(){

	Serial.begin(9600);

	pinMode(RFIDResetPin, OUTPUT);
	digitalWrite(RFIDResetPin, HIGH);

	//ONLY NEEDED IF CONTROLING THESE PINS - EG. LEDs
	pinMode(2, OUTPUT);
	pinMode(3, OUTPUT);
}

void loop(){

  char tagString[13];
  int index = 0;
  boolean reading = false;

  while(Serial.available()){

    int readByte = Serial.read(); //read next available byte

    if(readByte == 2) reading = true; //begining of tag
    if(readByte == 3) reading = false; //end of tag

    if(reading && readByte != 2 && readByte != 10 && readByte != 13){
      //store the tag
      tagString[index] = readByte;
      index ++;
    }
  }

  checkTag(tagString); //Check if it is a match
  clearTag(tagString); //Clear the char of all value
  resetReader(); //eset the RFID reader
}

void checkTag(char tag[]) {
///////////////////////////////////
//Check the read tag against known tags
///////////////////////////////////

  if(strlen(tag) == 0) {
  	return; //empty, no need to contunue
  }


	time_t t = now();

  if (compareTag(tag, tag1)) {
    if (canDispense(t, cat1last)) {
    	cat1last = t;
    	lastFeeding = t;
    	lightLED(2);
    	dispenseFood(cat1amount);
    } else {
    	lightLED(3);
    }
  } else if (compareTag(tag, tag2)) {
    if (canDispense(t, cat2last)) {
    	cat2last = t;
    	lastFeeding = t;
    	lightLED(2);
    	dispenseFood(cat2amount);
    } else {
    	lightLED(3);
    }
  } else {
    Serial.println(tag); //read out any unknown tag
  }
  delay(1100);
}

bool canDispense(time_t currentTime, int lastTime) {

	if (currentTime <= GLOBAL_DELAY || currentTime <= FEED_DELAY) {
		return false;
	}

	// if we've never fed before, then yes
	if (lastFeeding == 0) {
		return true;
	}

	// if we have fed before and it was more than 15 seconds ago
	if (currentTime - GLOBAL_DELAY > lastFeeding ) {
		if (lastTime == 0) {
			return true;
		}
		// if the last time we fed this cat was over 30 seconds ago.
		if (lastTime > 0 && currentTime - FEED_DELAY > lastTime) {
			return true;
		}
	}

	return false;
}

void dispenseFood(int amount) {

}

void lightLED(int pin){
///////////////////////////////////
//Turn on LED on pin "pin" for 250ms
///////////////////////////////////
  Serial.println(pin);

  digitalWrite(pin, HIGH);
  delay(250);
  digitalWrite(pin, LOW);
}

void resetReader(){
///////////////////////////////////
//Reset the RFID reader to read again.
///////////////////////////////////
  digitalWrite(RFIDResetPin, LOW);
  digitalWrite(RFIDResetPin, HIGH);
  delay(150);
}

void clearTag(char one[]){
///////////////////////////////////
//clear the char array by filling with null - ASCII 0
//Will think same tag has been read otherwise
///////////////////////////////////
  for(int i = 0; i < strlen(one); i++){
    one[i] = 0;
  }
}

boolean compareTag(char one[], char two[]){
///////////////////////////////////
//compare two value to see if same,
//strcmp not working 100% so we do this
///////////////////////////////////

  if(strlen(one) == 0) return false; //empty

  for(int i = 0; i < 12; i++){
    if(one[i] != two[i]) return false;
  }

  return true; //no mismatches
}