Anyway, I did take a break yesterday afternoon. I had to, because I got an arduino, a parallax rfid antenna and some rfid tags in the mail. You see, we need a better cat door and yesterday I got started on the KD2000 (Kitty Door 2000) by adapting the reader code from arduino.cc. I've modified to make it work with my tags.
int val = 0;
char code[12]; //The arduino.cc code shows a [10]. You may need to put [12] in here. This solved a major frustration for me.
int bytesread = 0;
int ledPin = 3; //I wanted to prototype some interactivity, so I attached an led to digital pin 3.
/* In defining the variables for the tags, you'll want to list these as arrays separated by commas. For example:
char Biscuit[12] = "3600738183" didn't work for me.
I then revised that to do if(strcmp(code,Biscuit == 0)... That didn't work. It was all in how I defined Biscuit as a string. See below. */
char Biscuit[12] = {'3', '6', '0', '0', '7', '3', '8', '1', '8', '3'}; //These are obviously the tags. With these arrays, the strcmp function worked.
char Marathon[12] = {'3', '6', '0', '0', '8', 'A', '9', '4', '4', '3'};
char Max[12] = {'3', '6', '0', '0', '5', 'C', '6', 'F', '3', '6'};
char Sage[12] = {'3', '6', '0', '0', '5', 'C', '2', 'F', 'B', '2'};
char Veeps[12] = {'3', '6', '0', '0', '5', 'B', '8', '6', 'C', '6'};
void setup() {
Serial.begin(2400); // RFID reader SOUT pin connected to Serial RX pin at 2400bps
pinMode(2,OUTPUT); // Set digital pin 2 as OUTPUT to connect it to the RFID /ENABLE pin
digitalWrite(2, LOW); // Activate the RFID reader
pinMode(3,OUTPUT); // for the led on/off
}
void loop() {
if(Serial.available() > 0) { // if data available from reader
if((val = Serial.read()) == 10) { // check for header
bytesread = 0;
while(bytesread<10) { // read 10 digit code
if( Serial.available() > 0) {
val = Serial.read();
if((val == 10)||(val == 13)) { // if header or stop bytes before the 10 digit reading
break; // stop reading
}
code[bytesread] = val; // add the digit
bytesread++; // ready to read next digit
}
}
if(bytesread == 10) { // if 10 digit read is complete
Serial.print("TAG code is: "); // possibly a good TAG
Serial.println(code); // print the TAG code
{
if(strcmp(code,Biscuit) == 0) { //This is my own code. Not hard. There's probably a way to do this all in one line by having the the if statement run through the list of tags.
Serial.println("Biscuit, you're in");
}
if(strcmp(code,Marathon) == 0) {
Serial.println("Marathon, you're in.");
}
if(strcmp(code,Max) == 0) {
Serial.println("Max, you're in.");
}
if(strcmp(code,Sage) == 0) {
Serial.println("Sagebrush, you're in.");
}
if(strcmp(code,Veeps) == 0) {
Serial.println("Veeps, you're in.");
digitalWrite(ledPin, HIGH); // sets the LED on
delay(250); // waits for a second
digitalWrite(ledPin, LOW); // sets the LED off
}
if((strcmp(code,Biscuit) !=0) && (strcmp(code,Marathon) != 0) && (strcmp(code,Max) !=0) && (strcmp(code,Sage) !=0) && (strcmp(code,Veeps) !=0)) {
Serial.println("Illegal attempted entry"); //Any cat that shows up with an rfid will be denied and it will go on record.
Serial.println(code);
{
}}}}
bytesread = 0;
delay(1000); // wait for a second
}
}
}
// extra stuff
// digitalWrite(2, HIGH); // deactivate RFID reader
It took me a while, but now everything is working. I know my engineering and math friends will be able to cut this down to 25% of its current length. Nonetheless, the "proof of concept" (the proof of the concept that I could do this) worked. Of course, lots of tweaking remains for the servo, a clock, and the mandatory network interface for twittering. Luckily I've got friends to help do this--I'm going to need them.
Here's a screenshot from the arduino serial window:
A virtual cat just came in the house.
The biggest challenge will be getting a better name for this thing.
