multi rfid reader with a twist, will it work?

Im new to this…but I have a project that Id like to use Arduino for. Im trying to picture an RFID reader remotely located from the Arduino Uno and when the tag is scanned, it creates a audible buzz with a blinking LED and displays the users name on a monochrome 128x32 OLED screen at the location of the Arduino. Im just not sure if the Arduino Uno can drive 2 seperate RFID readers.

At the Uno, It would utilize the PN532 RFID/NFC shield (to read and write the tags), then obviously, the remote reader is (theoretically) connected back to the Arduino.

The only real need for the shield would be to create the tag with user specific information (assigned location, name, etc…
My concern is the remote reader. WIll this be an issue? Can a Parallax reader be used in conjunction with the PN532, while using the Mifare key fob tags? If not, what do I need? Are there different writable key fob tags that can be used?

The information would have to be written to the tag manually, from workstation side software (what software can do this?). It’s there an interface that is idiot proof…like the nfc writer apps for android? I’d rather not have to have the code modified every time for each new user tag that will need to be created.

So, concept of operation:
User needs a tag
goes to location of Arduino, gets tag created with " John Doe" name and work location, from the PN532
John Doe wants to enter a room, swipes tag in front of remote reader
Buzzer and LED go off, and OLED screen displays “User: John Doe”
Person at display location (uses a different system) buzzes John in.

Once I get this CONOPS working, Ill have to implement data logging with timestamp, for every RFID tag that is read on remote reader.

How can I ensure that once I write to the tag, that only I can rewrite to the tag? What about protecting the information on the tag, so it doesnt get “lifted” while at a coffee shop or other places where users get complacent?

Is this feasible? Main purpose is a notification system(dumbed down access control).

If there is a better/easier way of doing this, please let me know.

Thanks in advance, and I look forward to playing with Arduino.

Gototags.com have a free pc based download that wil do nfc tags. Needs a usb reader writer thiugh.

Thanks. I like free!

Any thoughts on the other info?

Im just not sure if the Arduino Uno can drive 2 seperate RFID readers.

No. It isn't a matter of driving two readers. It's a matter of responding to two readers. Since most readers use Serial (or SoftwareSerial) to communicate with the Arduino, and since the Arduino only has one hardware serial port and can only listen to one software serial port at a time, you can't use two software serial instances, and don't want to use the one hardware serial instance and one software serial instance, at the same time.

Turb02: Mifare key fob tags? If not, what do I need? Are there different writable key fob tags that can be used?

There are several different tags out there.

How can I ensure that once I write to the tag, that only I can rewrite to the tag? What about protecting the information on the tag, so it doesnt get "lifted" while at a coffee shop or other places where users get complacent?

Tags can be made read only.

Nfc formatted tags though can be read by anyone with a suitable app and phone.

Other formats have encryption built in but require custom software to read write.

Common mifare tags support encryption but if formatted as an nfc tag can be cloned.

So after reviewing the gototags info, Im thinking this:

USB reader/writer: http://help.buynfctags.com/hc/en-us/articles/200816557-ACS-ACR122U-NFC-Reader-Writer Windows software: http://support.gototags.com/hc/en-us/articles/200330196-GoToTags-Windows-NFC-App Arduino Uno R3 http://www.adafruit.com/products/50 Adafruit RFID Breakout board http://www.adafruit.com/products/364 What is the maximum distance from the Arduino that the RFID reader can be? OLED display http://www.adafruit.com/products/661 MiFare classic 13.56 MHz tag http://www.adafruit.com/products/363

Keep in mind that Id like to format the cards with NDEF so I can add custom identifiable user information to them. Once I get the above working, Id like to add an audible chirp or buzzer, visible light notification (blinking LED), and logging capability using: http://www.adafruit.com/products/1141

Any insight or better hardware for what Im trying to accomplish, which is a mere RFID user identification system?

Any input? Id like to get started ordering the parts listed…if they will all work together, and the distance of the RFID from the Arduino is of no concern.

First two inks are an out of the box solution to get going with .

The other gear will do the same thing once your programme is written.

Reaad distance depends on the tag size or rather the tag aerial size. For a cc sized tag up to 10 cm.

Be aware though that this is not a beginners programming excercise. Programming the reader will require a lot reading of reference material regarding the reader chip , its a few hundred pages long.

I have most of the bits in your list for a similar application, i have been reading for about 2 months now and am barely off the drawing board. So far i can read the uid of a card and serial output it. Still working on reading what is actually on the card.

The uid is unique to every card so may be enough for you. Just have a programmed lookup table that references the card no to a name would be simpler to implement. Boilerplate programmes that read the uid are available online.

The distance Im referencing is the actual physical distance of the RFID sensor from the Arduino, not the tag from the RFID reader.

How long of a cable can be ran: RFID reader_________________________eg: 75 ft.____________________________Arduino RFID reader_______eg: 15 ft___Arduino

Reading the documentation is not a problem for me, I work nights...now understanding everything its talking about may be a different story ;)

I read somewhere that the tags need to be formatted for NDEF for custom content to be coded to them.

So for starters, Id like to get at least an order of the RFID card and the Arduino placed. Do you know of another Mifare rfid reader that would work? Maybe something a little smaller than the breakout board from Adafruit?

Ok The reader shield communicates with the arduino with either I2C or SPI interface. These are totally unsuitable for distance communication purposes. The reader and shield must be co sited with distance comunication being sone with rs 232 or similar..

Smaller readers , which are much cheaper than the addafruit ones can be had from chinese supliers. They ar about 1/2 size and exclusuvley use the spi interface..

Arduino plus reader chip shield is probably not ideal for your application.

It sounds to me that you need a reader with a serial interface which can be had ready built from various suppliers. This would also avoid the hasle of writing your own reader software.

The adafruit breakout board can use either i2c or serial. Why would this not work?

Do you have a link to a reader that would work at a distance away from the Arduino AND read mifare (13.56Mhz) tags?

Distance between reader and arduino should not be a problem if you choose a reader with Wiegand outputs. Several of these can be connected to the arduino at the same time and read using the pin change interrupt system.

You are wanting to store the user information on the tag rather than the system which is a bit unusual, normally you have just a number and a database in the controller.

Why is it unusual to store the user data on the tag? Not a sarcastic question. Im trying to get a notification center created where the person at the desk can see who is at the door, based on the tag that is scanned. My impression was that I could custom code the tags with the users name and have it displayed on the LCD, viewed by the person at the desk, and logged on the data logger card. Essentially an access control system that only provides the notification and logging, not actually unlocking the door.

Id rather not have to build a database that ties a specific number (tag ID) to a user name, then rely on the Arduino to parse through a database (of sorts) stored on itself, to come up with the user name and display it.

Is what Im wanting to achieve, out of reach?

Ive also looked into XBee (still reading up on it) and this may be what I need to send the serial output from the RFID to the Arduino, but Im still reading up on it. Not sure how the remote unit would get power just yet...

Thanks for all the input!! Keep it coming.

Turb02: Why is it unusual to store the user data on the tag?

Because it can be cloned if you use the ndef format. The uid cannot

Mifare tags however support more secure communication but have to be programmed.

Is what Im wanting to achieve, out of reach?

No .

Ive

Boardburner2: Because it can be cloned. The uid cannot.

So...Either have that risk, or try to train someone with no coding background to edit the code every time a new UID is handed out to a new user? Damn! Really no way around some sort of "hole" in my idea...

There would be no sensitive data on it, literally just a first and last name...what a conundrum.

So, while I think of the acceptable risk of the above mentioned, thoughts on XBee to transmit from RFID to Arduino?

Ive found some online info regarding this, but most of them are using the RFID and XBee connected to a stand alone Arduino that then transmits to a remote Arduino with XBee. Is there a way to NOT have a Arduino at the RFID/XBee? So: RFID & XBee combo ~~(wifi transmit)~~XBee & Arduino combo with LCD display and data logger.

Can the RFID combo be battery powered? EDIT: Yes it can http:// vimeo.com/3587659 (remove the space)

Now, I really gotta sink my head around the "security hole" in my project...Any help or input is appreciated.

I really want this project to be stand alone (off the network) so tying into a DB of users is out of the question, and so is handjamming every one of them into a spreadsheet/DB on the Arduino. That still leaves me with the issue of getting the tags cloned, or having a non tech person diving into the code for every new tag created.

Turb02: Id rather not have to build a database that ties a specific number (tag ID) to a user name, then rely on the Arduino to parse through a database (of sorts) stored on itself, to come up with the user name and display it.

It would be an awflul lo easier to write that than write the code needed for secure card reading. Stand alone access units can be had where the programming is as simple as presenting a master tag to the reader followed by the new tag. Lots of variations possible depending on yyounprogramming skills.