NFC library for Raspberry Pi

This is a port of Seeed Studios's PN532 Arduino Library for using the PN532 chip with Raspberry Pi.

Features

Support all interfaces of PN532 (I2C, SPI, HSU)
Read/write Mifare Classic Card
Communicate with android 4.0+(Lists of devices supported)
Card emulation (NFC Type 4 tag)

To Do

Works with Don's NDEF Library
To support more than one INFO PDU of P2P communication
To read/write NFC Type 4 tag

Getting Started

PyPI
1. Install with pip
```
pip install pn532pi
```
2. Follow examples
Direct Download
1. Download zip file and extract the 4 folders(pn532pi, quick2wire, examples and test)
2. Follow the examples of the two libraries.
Clone Git Repository
1. Get pn532 library
```
  git clone --recursive https://github.com/gassajor000/pn532pi.git
```
2. Follow the examples of the two libraries

Power

The Raspberry Pi 3.3v regulator does not provide enough current to drive the PN532 chip. If you try to run the PN532 off your Raspberry Pi 3.3v it will reset randomly and may not respond to commands. Instead you will need another power source (3.3v or 5v) to power the PN532. It is generally safe to tap into the 5v pin on the Raspberry Pi so long as your power supply can provide enough power for the PN532 and the pi.

I2C Interface

I2C is short for Inter-integrated Circuit. I2C interface needs only 4 wires to connect PN532 with Raspbeery Pi.

To use the I2C bus 1 to control PN532, refer to the code below.

from pn532pi import Pn532I2c, Pn532
	
i2c = Pn532I2c(1)
nfc = Pn532(i2c)

def setup():
    nfc.begin()
    # ...

Examples

To run an example you will need to change the interface flags to the interface you are using. For SPI you may also have to change the slave select pin to the pin you have connected.

# Set the desired interface to True
SPI = True
I2C = False
HSU = False

...
if SPI:
    PN532_SPI = Pn532Spi(Pn532Spi.SS0_GPIO8)
    nfc = Pn532(PN532_SPI)

Then you can just call python <example file>.py from a terminal.

Help debugging

We are willing to provide debug help for this library however there is currently only one maintainer doing this in his free time. Don't be surprised if responses take a couple days. Also, as hardware issues can be quite difficult to debug remotely, if your issue cannot be replicated using the test setup (pi 3B+) then there may not be much we can do.

For Remote IO Errors (I2C communciation errors) we also require that you take a logic capture of the i2c failure. This is needed to determine whether the pi or the nfc chip is the cause of the communication failure. Below is a recommendation for an affordable logic analyzer that can be run with the opensource Pulse View application or with the Selaea app.

HiLetgo USB Logic Analyzer

Contribution

It's based on Adafruit_NFCShield_I2C. Seeed Studio rewrite the library to make it easy to support different interfaces and platforms. @Don writes the NDEF library to make it more easy to use. @JiapengLi adds HSU interface. @awieser adds card emulation function. @gassajor000 ported to python/Raspberry Pi

[Mega]: http://arduino.cc/en/Main/ arduinoBoardMega [DUE]: http://arduino.cc/en/Main/arduinoBoardDue [Leonardo]: http://arduino.cc/en/Main/arduinoBoardLeonardo [SoftwareSerial]: https://www.arduino.cc/en/Reference/softwareSerial

Images courtesy of pinout.xyz, components101.com, sparkfun.com

gassajor000/pn532pi