Multiple RFID readers, one Pi


3 posts
by samgray111 » Sat Apr 20, 2013 11:02 pm
Hi there,

Please bear with me as I'm just in the early stages of planning this as part of a university project,

I am trying to find a method of connecting multiple RFID readers to the Raspberry Pi, however In addition, I would also need a method of detecting which reader was activated.

I was hoping to use the following readers, http://www.ebay.co.uk/itm/170976906170, simply because I already have one. These readers are very simple to use, they work completely plug-and-play on the Raspi and upon scanning a tag/card, they will simply input the string of the token into the active program (as if it was just a keyboard/generic input device)

The way in which I was kind of thinking of detecting which device was activated was to simply add a prefix to the input string, then I could simply parse the first couple of digits of this input and work out which reader it came from. This is just a vague idea at the minute and to be honest, I would have no idea where to start to identify even which USB port is being used.

I am completely open to using 'component' RFID Wiegand readers as I understand many people have done successfully, however (and this is where my knowledge gets VERY shaky) as I understand it, You would do this using the I2C bus of the Pi? and there is only one input for this?

My language of choice would be C++ or Python, however I'm happy to learn what I have to! :-)

My budget is fairly low and so I would ideally like to stick to readily available cheap readers such as the one I linked to earlier or, if a wiegand reader, something like the following http://www.ebay.co.uk/itm/251211288263.

Absolutely any help you guys would be able to offer would be much appreciated, as I say, this is very much just my initial thoughts on the project and I understand I am going to have to put a lot more thought into it yet.

Thanks in anticipation,

Sam
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by kencodes » Sat Jun 08, 2013 4:28 am
I'm not sure what has become of your multiple RFID reader project, but I am working on something similar and came across your post. I'm afraid that all I have to contribute to help you is a bit of information about the I2C bus. It is a multi-drop bus that can be used to connect many I2C compliant devices on the same two wire interface.

Were you successful in getting things to work?
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by assuncao » Wed Oct 23, 2013 1:00 pm
Hi guys,

I'm under the same need, I need connect about 16 RFID readers in one Pi. Were you successfully at this?
If yes, could you share the best solution?

Thanks in advanced!
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Joined: Mon Oct 21, 2013 7:24 pm