Has anyone successfully connected the Adafruit PN532 RFID Breakout board (https://www.adafruit.com/product/364) to a Photon? The only hookup instructions that I can find are for SPI, but the Adafruit_PN532 library that has been ported into Particle defaults to I2C. I don’t have a preference about which interface to use; I’d just like to get instructions about how to get the Photon and the breakout board talking.
Yup, PN532 RFID working with Photon and Xenon/Argon but not the Adafruit board you have referenced - rather a cheaper $4 version. I2C works fine (needs pull-up resistors to 3V3) and you need to also have the IRQ connected. So 3V3, GND, SDA, SCL, IRQ - 5 wires. The boards I use have small DIP switches to select the comms bus which can sometimes not make. The rest you should be able to figure from the software.
Thanks for the quick reply. Looking at the ported Adafruit library, I2C mode seems to also require an output from the Photon for “reset”. Did you find that you need this? (One extra pin, but I don’t mind if it is needed).
P.S. Do you have a link to buy the $4 version that you have working? I bought the Adafruit board for $40 because I thought that I’d develop my application with “quality” hardware and then deploy with a cheap board (hopefully isolating hardware problems from software).