Arduino wont print RFID tag #

Projects General Guidance
1

I have an Arduino Pro 16MHz 328 and a Parallax RFID Reader.
The reader is connected as follows:
Enable Pin = Pin2
Sout = Pin 0 (RX)

The script I'm using is here:
http://arduino.cc/playground/Learning/PRFID

It complies and seems to run fine although the RFID led remains Red the entire time, but when I open the serial monitor it wont show anything. What is wrong?

Thanks!

2

Have you set the monitor window to 2400 baud in the lower right corner?

3

Grumpy_Mike:
Have you set the monitor window to 2400 baud in the lower right corner?

Yeah,
I selected 2400 baud in the drop down selection. Do I need to click/ type anything after selecting the baud in the drop down window? :frowning:

Any other ideas? Doubt it is a faulty RFID reader. I know everything is soldered correctly. I have to be missing a step.

  1. Selected my Arduino Board and Com Port 3
  2. Pasted the code into the Arduino software
  3. Uploaded with no compiling errors.
  4. RFID starts up flashes green and then flashes and remains red. If I hold the card in front of the reader the Red led goes dim but nothing prints.
4

Put a Serial.println("Some text"); after your Serial.begin. Does it appear on the monitor?

5

wildbill:
Put a Serial.println("Some text"); after your Serial.begin. Does it appear on the monitor?

I'll be able to try this tomorrow and let you know!

6

pwnm30rdi3:

wildbill:
Put a Serial.println("Some text"); after your Serial.begin. Does it appear on the monitor?

I'll be able to try this tomorrow and let you know!

It prints the "Some text" but it fails to print anything else.
Could it be a bad RFID reader?

7

Are you using the right sort of tags, that is EM41000 types.

8

Grumpy_Mike:
Are you using the right sort of tags, that is EM41000 types.

They came in a kit together from Parallax.
It shouldn't be the code since I copied it straight from Arduino's playground.
What else could it be?

Picture of Arduino Pro

807×1080 158 KB

Picture of RFID Reader

807×1080 100 KB

9

although the RFID led remains Red the entire time

Does that include when a token is presented?
If so all I can think is that the reader is not working.
Have you got a scope so you can check signals?

10

Grumpy_Mike:

although the RFID led remains Red the entire time

Does that include when a token is presented?
If so all I can think is that the reader is not working.
Have you got a scope so you can check signals?

The LED does remain solid red while the token is present. I ordered a second reader and it should be arriving sometime today.
I do not have a scope :frowning:

11

I switched the readers out... Same problem. What could it be now?
Also I just tried this guys code: http://www.gumbolabs.org/2009/10/17/parallax-rfid-reader-arduino/
It still wouldn't do anything?

It has to be the Arduino?

12

When you disable the reader does the LED turn green?

13

Grumpy_Mike:
When you disable the reader does the LED turn green?

When I wave the card and/ or hold it in front of the reader nothing happens.

When I turn the arduino pro on the Reader's light turns green for like 2 seconds and then turns reds though.

14

Did you not understand that?
In order to find out what is wrong you need to test things. So you need to write a sketch that toggles the enable line like a flashing LED.
Then you need to see if you are getting anything from the serial port. To do this I would suggest you power the arduino sepratly, not from the USB and blink an LED every time you see any character from the serial port. By having the USB disconnected you remove the problem of two signals fighting to control the RX line. Does your arduino have a 1K seriese resistor. I ask because it is only an arduino clone, not a real one and it might be the issue.

Finally you could try recieving data on another pin using the new software serial library.

15

Grumpy_Mike:
Did you not understand that?
In order to find out what is wrong you need to test things. So you need to write a sketch that toggles the enable line like a flashing LED.
Then you need to see if you are getting anything from the serial port. To do this I would suggest you power the arduino sepratly, not from the USB and blink an LED every time you see any character from the serial port. By having the USB disconnected you remove the problem of two signals fighting to control the RX line. Does your arduino have a 1K seriese resistor. I ask because it is only an arduino clone, not a real one and it might be the issue.

Finally you could try recieving data on another pin using the new software serial library.

I do understand now! Thank you so much for taking the time to explain it.
I tested the /enable line and the LED remained Green when Disabled.
Then i tested the serial port on the "fake" arduino.
Turns out the serial port is dead? So I am now using port 8 (: & it works!!!

Now for some reason the script is not working:
http://pastebin.com/raw.php?i=jMvVLmvG

Compiles fine and to me looks like it should work just fine.

16

It has me stumped anyone else have an idea?

17

Turns out the serial port is dead? So I am now using port 8

Not sure I understand that.

Now for some reason the script is not working:

So in what way is it not working?

I would put this code:-

	SoftwareSerial RFID = SoftwareSerial(rxPin,txPin); 
	RFID.begin(2400);

In the setup() function, you don't want to initialise it every time through the loop.

Again you should dig in an put some debug print statements in that code to see where it is going to and work out where it is getting stuck.
So for example after the comment:-
// Read the full code
print out a message to say you have received something.

replace

return; // Incomplete packet

with

{ serial.print("Incomplete packet"); return; }// Incomplete packet

and so on and find out what is not happening.