May 8, 2011 AT 12:00 am

Using an AVR as an RFID tag

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Using an AVR as an RFID tag, Beth writes…

Last time, I posted an ultra-simple “from scratch” RFID reader, which uses no application-specific components: just a Propeller microcontroller and a few passive components. This time, I tried the opposite: building an RFID tag using no application-specific parts.

Well, my solution is full of dirty tricks, but the results aren’t half bad. I used an Atmel AVR microcontroller (the ATtiny85) and a coil. That’s it. You can optionally add a couple of capacitors to improve performance with some types of coils, but with this method it’s possible to build a working RFID tag just by soldering a small inductor to an AVR chip

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1 Comment

  1. Wow, this is really cool! I definitely have a lot to learn about how RFID works, and I can imagine this would be a fun tool for prototyping.

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