My plan was to build an RFID card based music player, something that gives back an element of the physical record / cd collection to digital music. This seemed like a relatively simple challenge and one of the most common RFID readers out there is the super-cheap RC522 reader.
These are widely available and others have had luck getting them to work with the pi.
Me, not so much. I failed to get two different versions of the RC522 to work with 2 different pi (the 2 and the 3b).
I was about to give up when I decided to switch approaches. Although I can do basic soldering, I’m no electronics genius and I suspect I was running into issues with the GPIO ports, so I switched over to this basic USB based RFID reader.
These things come under different names, but the link above is the one I bought. The EM4100_125k is a very basic RFID reader – it does not write to cards, nor does it read any other information beyond the cards serial number, but for my purposes it did the trick.
I had to hunt down a CD drive and used windows running on Parallels to run the setup file, but after setting it up to add the enter key after reading it runs great with a python script on the pi with very little fussing around. It was a hassle trying to find the hardware to get the setup file since I couldn’t find a download file, so that was the biggest delay in getting everything working.
Just be sure you’re getting the right cards to work with the correct frequency. I initially tried NFC ultralight cards that obviously did not work before ordering these 125khz cards that do work.
I intend to post more info about my RFID based music box project soon!