A node module that uses libusb to interface with NFC reader/writers.

UNDER DEVELOPMENT. It can blink LEDs and beep on ACR122 NFC reader/writers, but there isn't much useful beyond that. (See test.js)

It is also chatty, and will log to your console.

sudo apt-get install libusb-dev
git clone https://github.com/andrewjjenkins/nfc
cd nfc
npm install
(plug in an NFC reader that's compatible, currently ACR122)
node test.js

There will be a top-level abstraction for opening readers, telling those readers what kinds of cards to listen for, programming secure exchange keys, etc. It should be device agnostic. This is currently a work-in-progress, I only own one device so the correct abstraction is not clear to me yet.

Every device should have:

• Totally generic methods and events: init(), .on('card', ...)
• Device-specific routines: setLed()
• Chip-specific routines: inListPassiveTarget()

var nfc = require('nfc');
nfc.open(function (err, device) {
  if (err) {
    throw err;
  }
  console.log('Opened NFC device:', device);
  device.setLed({red: true}, function (err, data) { ... });
});

Walk the list of devices (in lib/devices.js), trying to open each one. If one succeeds, call the callback with the opened device. If none can be successfully opened, call the callback with an error.

Devices have device-specific APIs. Currently, the only supported device is the ACR122. The ACR122 has a PN532 chip on it, so it also inherits all of the pn53x methods.

Sends a command to power on the device. This is automatically done as part of the device opening and initialization. You only have to call it if you power down the device.

Turns the red and/or green LEDs on and off, and optionally blinks them along with the buzzer. There are two modes: blinking mode and non-blinking mode. Non-blinking mode just turns the LEDs on and off; to use non-blinking mode, don't pass any of the blink-related options. Blinking mode will blink the LEDs and optionally the buzzer according to the options, and then stop with the LEDs and buzzer off.

Options:

• red: Turn the red LED on (non-blinking mode), or blink the red LED (blinking mode). Both red and green can be set.
• green: Turn the green LED on (non-blinking mode), or blink the green LED (blinking mode). Both red and green can be set.
• blinkDuration: Duration to blink the LED in milliseconds, precision is 100ms. Minimum duration is 100ms.
• blinkDutyCycle: Proportion of the blinkDuration that the LEDs should be on and (optionally) the buzzer buzzing. Between 0 and 1, defaults to 0.5 (50%).
• blinkCount: Number of times to repeat blink. Defaults to 2.
• buzzer: Sound the buzzer when blinking.

Example of turning the red LED on forever:

device.setLed({red: true }, cb);

Example of blinking the red and green LEDs (making a yellow light) 3 times, with 300 ms on and 200 ms off, with the buzzer sounding:

device.setLedAndBuzzer({red: true, green: true, blinkDuration: 500,
                        blinkDutyCycle: 0.6, blinkCount: 3, buzzer: true });

Reads the firmware version from the ACR122 device and delivers it to the callback as an ASCII string.

device.getFirmwareVersion(function (err, version) {
  console.log('Version:', version); // Version: ACR122U213

If on is truthy, tells the ACR122 to buzz the buzzer when a card is near and it is ready to read.

Sets the PICC mode to start polling cards from the reader.

Options:

• auto: Enable auto PICC polling (default: true)
• autoAts: Automatically issue ATS requests whenever an ISO14443-4 Type A tag is activated. If enabled, prevents reading MiFARE tags. Default: false.
• pollingInterval: Polling interval in milliseconds; only 250ms and 500ms are supported (default: 250).
• felica424k: Detect FeliCa 424K tags (default: true).
• felica424k: Detect FeliCa 212K tags (default: true).
• topaz: Detect topaz tags (default: true).
• iso14443B: Detect ISO14443 Type B tags (default: true).
• iso14443A: Detect ISO14443-4 Type A tags (default: true). Must be true, and autoAts must be false, for reading MiFARE tags.

Gets the chip firmware version. The raw object is the bytes read off the wire, in case future chips are not compatible with the decoding routine (patches strongly desired in this case). function cb(err, result) gets a result that looks like:

{ ic: 'PN532',
  version: '1.6',
  iso18092: true,
  iso18443B: true,
  iso18443A: true,
  raw : {  ... } }

Gets the general status of the reader, including any tags present. The pn53x can only see one tag at a time. The raw object is the bytes off the wire. The result looks like this if there is no tag present:

{ tags: [],
  field: false,
  raw:  { ... } }

If a tag is present, it will look like:

{ tags: [ { rxRate: '106Kbps',
            txRate: '106Kbps',
            type: 'MiFare/RFA/ISO14443-3A/ISO14443-3B/ISO18092 passive 106Kbps',
            raw: { ... } } ],
  field: false,
  raw: { ... } }

The nfc node module, documentation, tests, and build scripts are licensed under the MIT license:

Copyright Andrew Jenkins [email protected]

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.