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Dual RFID Readers

I have an application that needs two RFID readers. Because these RFID readers are SPI devices, they can be connected to the same two data pins (MISO & MOSI), and clock pin (SCK), and only two pins (SDA & RST)  have to be unique. This makes a total of 7 data pins, plus 3.3v and Gnd. I’m taking the 5 sets of serial numbers, and adding them together, and making each reader accept a different set of numbers. Run the serial monitor, scan your badge or keyfob, and then enter the total code into your sketch to make it active. You could have two security doors, and one badge will get you through one, but a different badge can get you through both. Get the code and library here!

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Limaj Francisco
7 years ago

can you give me the wire connection of 2 rfid reader and arduino?

Steve Spence
7 years ago

It's listed in the code.

6 years ago

Hello. thanks for share your code. i want to know is it possible to join 4 or 5 MFRC522 to one Arduino?

Steve Spence
6 years ago

sure, just keep in mind each unit requires two unique pins, the other two pins are shared.

5 years ago

Hi Steve, just want to say thank you for sharing this project!


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