Rust - NFC Bricklet

This is the description of the Rust API bindings for the NFC Bricklet. General information and technical specifications for the NFC Bricklet are summarized in its hardware description.

An installation guide for the Rust API bindings is part of their general description. Additional documentation can be found on docs.rs.

Examples

The example code below is Public Domain (CC0 1.0).

Scan For Tags

Download (example_scan_for_tags.rs)

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use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, nfc_bricklet::*};

const HOST: &str = "127.0.0.1";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your NFC Bricklet

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection
    let nfc = NfcBricklet::new(UID, &ipcon); // Create device object

    ipcon.connect((HOST, PORT)).recv()??; // Connect to brickd
                                          // Don't use device before ipcon is connected

    let reader_state_changed_receiver = nfc.get_reader_state_changed_callback_receiver();

    // Spawn thread to handle received events.
    // This thread ends when the `nfc` object
    // is dropped, so there is no need for manual cleanup.
    let nfc_copy = nfc.clone(); //Device objects don't implement Sync, so they can't be shared between threads (by reference). So clone the device and move the copy.
    thread::spawn(move || {
        for state_change in reader_state_changed_receiver {
            if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_READY {
                let (tag_id, tag_type) = nfc_copy.reader_get_tag_id().unwrap();
                println!("Found tag of type {} with ID {:x?}", tag_type, tag_id);
            } else if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_ERROR {
                println!("Request tag ID error");
            }
            if state_change.idle {
                nfc_copy.reader_request_tag_id();
            }
        }
    });

    // Enable reader mode
    nfc.set_mode(NFC_BRICKLET_MODE_READER);

    println!("Press enter to exit.");
    let mut _input = String::new();
    io::stdin().read_line(&mut _input)?;
    ipcon.disconnect();
    Ok(())
}

Emulate Ndef

Download (example_emulate_ndef.rs)

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use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, nfc_bricklet::*};

const HOST: &str = "127.0.0.1";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your NFC Bricklet
const NDEF_URI: &str = "www.tinkerforge.com";

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection
    let nfc = NfcBricklet::new(UID, &ipcon); // Create device object

    ipcon.connect((HOST, PORT)).recv()??; // Connect to brickd
                                          // Don't use device before ipcon is connected

    let cardemu_state_changed_receiver = nfc.get_cardemu_state_changed_callback_receiver();

    // Spawn thread to handle received events.
    // This thread ends when the `nfc` object
    // is dropped, so there is no need for manual cleanup.
    let nfc_copy = nfc.clone(); //Device objects don't implement Sync, so they can't be shared between threads (by reference). So clone the device and move the copy.
    thread::spawn(move || {
        for state_change in cardemu_state_changed_receiver {
            if state_change.state == NFC_BRICKLET_CARDEMU_STATE_IDLE {
                let mut ndef_record_udi = vec![0xd1u8, 0x01, NDEF_URI.len() as u8 + 1, 'U' as u8, 0x04];

                // Only short records are supported
                for byte in NDEF_URI.bytes() {
                    ndef_record_udi.push(byte);
                }

                if let Err(e) = nfc_copy.cardemu_write_ndef(&ndef_record_udi) {
                    println!("Error while writing ndef {}", e);
                }
                nfc_copy.cardemu_start_discovery();
            }
            if state_change.state == NFC_BRICKLET_CARDEMU_STATE_DISCOVER_READY {
                nfc_copy.cardemu_start_transfer(NFC_BRICKLET_CARDEMU_TRANSFER_WRITE);
            } else if state_change.state == NFC_BRICKLET_CARDEMU_STATE_DISCOVER_ERROR {
                println!("Discover error");
            } else if state_change.state == NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF_ERROR {
                println!("Transfer NDEF error");
            }
        }
    });

    // Enable cardemu mode
    nfc.set_mode(NFC_BRICKLET_MODE_CARDEMU);

    println!("Press enter to exit.");
    let mut _input = String::new();
    io::stdin().read_line(&mut _input)?;
    ipcon.disconnect();
    Ok(())
}

Write Read Type2

Download (example_write_read_type2.rs)

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use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, nfc_bricklet::*};

const HOST: &str = "127.0.0.1";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your NFC Bricklet

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection
    let nfc = NfcBricklet::new(UID, &ipcon); // Create device object

    ipcon.connect((HOST, PORT)).recv()??; // Connect to brickd
                                          // Don't use device before ipcon is connected

    let reader_state_changed_receiver = nfc.get_reader_state_changed_callback_receiver();

    // Spawn thread to handle received events.
    // This thread ends when the `nfc` object
    // is dropped, so there is no need for manual cleanup.
    let nfc_copy = nfc.clone(); //Device objects don't implement Sync, so they can't be shared between threads (by reference). So clone the device and move the copy.
    thread::spawn(move || {
        for state_change in reader_state_changed_receiver {
            if state_change.state == NFC_BRICKLET_READER_STATE_IDLE {
                nfc_copy.reader_request_tag_id();
            } else if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_READY {
                let (tag_id, tag_type) = nfc_copy.reader_get_tag_id().unwrap();

                if tag_type != NFC_BRICKLET_TAG_TYPE_TYPE2 {
                    println!("Tag is not type-2");
                    return;
                }

                println!("Found tag of type {} with ID {:x?}", tag_type, tag_id);
                nfc_copy.reader_request_page(1, 4);
            } else if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_ERROR {
                println!("Request tag ID error");
            } else if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_PAGE_READY {
                let page = nfc_copy.reader_read_page().unwrap();

                println!("Page read: 0x{0:X} 0x{1:X} 0x{2:X} 0x{3:X}", page[0], page[1], page[2], page[3]);

                nfc_copy.reader_write_page(1, &page).unwrap();
            } else if state_change.state == NFC_BRICKLET_READER_STATE_WRITE_PAGE_READY {
                println!("Write page ready");
            } else if state_change.state == NFC_BRICKLET_READER_STATE_REQUEST_PAGE_ERROR {
                println!("Request page error");
            } else if state_change.state == NFC_BRICKLET_READER_STATE_WRITE_PAGE_ERROR {
                println!("Write page error");
            }
        }
    });

    // Enable reader mode
    nfc.set_mode(NFC_BRICKLET_MODE_READER);

    println!("Press enter to exit.");
    let mut _input = String::new();
    io::stdin().read_line(&mut _input)?;
    ipcon.disconnect();
    Ok(())
}

API

To allow non-blocking usage, nearly every function of the Rust bindings returns a wrapper around a mpsc::Receiver. To block until the function has finished and get your result, call one of the receiver's recv variants. Those return either the result sent by the device, or any error occured.

Functions returning a result directly will block until the device has finished processing the request.

All functions listed below are thread-safe, those which return a receiver are lock-free.

Basic Functions

pub fn NfcBricklet::new(uid: &str, ip_connection: &IpConnection) → NfcBricklet

Creates a new NfcBricklet object with the unique device ID uid and adds it to the IPConnection ipcon:

This device object can be used after the IP connection has been connected (see examples above).

pub fn NfcBricklet::set_mode(&self, mode: u8) → ConvertingReceiver<()>

Sets the mode. The NFC Bricklet supports four modes:

  • Off
  • Card Emulation (Cardemu): Emulates a tag for other readers
  • Peer to Peer (P2P): Exchange data with other readers
  • Reader: Reads and writes tags

If you change a mode, the Bricklet will reconfigure the hardware for this mode. Therefore, you can only use functions corresponding to the current mode. For example, in Reader mode you can only use Reader functions.

The default mode is "off".

The following constants are available for this function:

  • NFC_BRICKLET_MODE_OFF = 0
  • NFC_BRICKLET_MODE_CARDEMU = 1
  • NFC_BRICKLET_MODE_P2P = 2
  • NFC_BRICKLET_MODE_READER = 3
pub fn NfcBricklet::get_mode(&self) → ConvertingReceiver<u8>

Returns the mode as set by NfcBricklet::set_mode.

The following constants are available for this function:

  • NFC_BRICKLET_MODE_OFF = 0
  • NFC_BRICKLET_MODE_CARDEMU = 1
  • NFC_BRICKLET_MODE_P2P = 2
  • NFC_BRICKLET_MODE_READER = 3
pub fn NfcBricklet::reader_request_tag_id(&self) → ConvertingReceiver<()>

To read or write a tag that is in proximity of the NFC Bricklet you first have to call this function with the expected tag type as parameter. It is no problem if you don't know the tag type. You can cycle through the available tag types until the tag answers the request.

Currently the following tag types are supported:

  • Mifare Classic
  • NFC Forum Type 1
  • NFC Forum Type 2
  • NFC Forum Type 3
  • NFC Forum Type 4

After you call NfcBricklet::reader_request_tag_id the NFC Bricklet will try to read the tag ID from the tag. After this process is done the state will change. You can either register the NfcBricklet::get_reader_state_changed_callback_receiver callback or you can poll NfcBricklet::reader_get_state to find out about the state change.

If the state changes to ReaderRequestTagIDError it means that either there was no tag present or that the tag has an incompatible type. If the state changes to ReaderRequestTagIDReady it means that a compatible tag was found and that the tag ID has been saved. You can now read out the tag ID by calling NfcBricklet::reader_get_tag_id.

If two tags are in the proximity of the NFC Bricklet, this function will cycle through the tags. To select a specific tag you have to call NfcBricklet::reader_request_tag_id until the correct tag ID is found.

In case of any ReaderError state the selection is lost and you have to start again by calling NfcBricklet::reader_request_tag_id.

pub fn NfcBricklet::reader_get_tag_id(&self) → Result<(Vec<u8>, u8), BrickletRecvTimeoutError>

Returns the tag type and the tag ID. This function can only be called if the NFC Bricklet is currently in one of the ReaderReady states. The returned tag ID is the tag ID that was saved through the last call of NfcBricklet::reader_request_tag_id.

To get the tag ID of a tag the approach is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to ReaderRequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. Call NfcBricklet::reader_get_tag_id

The following constants are available for this function:

  • NFC_BRICKLET_TAG_TYPE_MIFARE_CLASSIC = 0
  • NFC_BRICKLET_TAG_TYPE_TYPE1 = 1
  • NFC_BRICKLET_TAG_TYPE_TYPE2 = 2
  • NFC_BRICKLET_TAG_TYPE_TYPE3 = 3
  • NFC_BRICKLET_TAG_TYPE_TYPE4 = 4
pub fn NfcBricklet::reader_get_state(&self) → ConvertingReceiver<ReaderGetState>

Returns the current reader state of the NFC Bricklet.

On startup the Bricklet will be in the ReaderInitialization state. The initialization will only take about 20ms. After that it changes to ReaderIdle.

The Bricklet is also reinitialized if the mode is changed, see NfcBricklet::set_mode.

The functions of this Bricklet can be called in the ReaderIdle state and all of the ReaderReady and ReaderError states.

Example: If you call NfcBricklet::reader_request_page, the state will change to ReaderRequestPage until the reading of the page is finished. Then it will change to either ReaderRequestPageReady if it worked or to ReaderRequestPageError if it didn't. If the request worked you can get the page by calling NfcBricklet::reader_read_page.

The same approach is used analogously for the other API functions.

The following constants are available for this function:

  • NFC_BRICKLET_READER_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_READER_STATE_IDLE = 128
  • NFC_BRICKLET_READER_STATE_ERROR = 192
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID = 2
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_READY = 130
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_ERROR = 194
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE = 3
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE_READY = 131
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE_ERROR = 195
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE = 4
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE_READY = 132
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE_ERROR = 196
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE = 5
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE_READY = 133
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE_ERROR = 197
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF = 6
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF_READY = 134
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF_ERROR = 198
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF = 7
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF_READY = 135
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF_ERROR = 199
pub fn NfcBricklet::reader_write_ndef(&self, ndef: u8) → Result<(), BrickletRecvTimeoutError>

Writes NDEF formated data with a maximum of 255 bytes.

This function currently supports NFC Forum Type 2 and 4.

The general approach for writing a NDEF message is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to ReaderRequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. If looking for a specific tag then call NfcBricklet::reader_get_tag_id and check if the expected tag was found, if it was not found got back to step 1
  4. Call NfcBricklet::reader_write_ndef with the NDEF message that you want to write
  5. Wait for state to change to ReaderWriteNDEFReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
pub fn NfcBricklet::reader_request_ndef(&self) → ConvertingReceiver<()>

Reads NDEF formated data from a tag.

This function currently supports NFC Forum Type 1, 2, 3 and 4.

The general approach for reading a NDEF message is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to RequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. If looking for a specific tag then call NfcBricklet::reader_get_tag_id and check if the expected tag was found, if it was not found got back to step 1
  4. Call NfcBricklet::reader_request_ndef
  5. Wait for state to change to ReaderRequestNDEFReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  6. Call NfcBricklet::reader_read_ndef to retrieve the NDEF message from the buffer
pub fn NfcBricklet::reader_read_ndef(&self) → Result<Vec<u8>, BrickletRecvTimeoutError>

Returns the NDEF data from an internal buffer. To fill the buffer with a NDEF message you have to call NfcBricklet::reader_request_ndef beforehand.

The buffer can have a size of up to 8192 bytes.

pub fn NfcBricklet::reader_authenticate_mifare_classic_page(&self, page: u16, key_number: u8, key: [u8; 6]) → ConvertingReceiver<()>

Mifare Classic tags use authentication. If you want to read from or write to a Mifare Classic page you have to authenticate it beforehand. Each page can be authenticated with two keys: A (key_number = 0) and B (key_number = 1). A new Mifare Classic tag that has not yet been written to can be accessed with key A and the default key [0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF].

The approach to read or write a Mifare Classic page is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to ReaderRequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. If looking for a specific tag then call NfcBricklet::reader_get_tag_id and check if the expected tag was found, if it was not found got back to step 1
  4. Call NfcBricklet::reader_authenticate_mifare_classic_page with page and key for the page
  5. Wait for state to change to ReaderAuthenticatingMifareClassicPageReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  6. Call NfcBricklet::reader_request_page or NfcBricklet::reader_write_page to read/write page

The authentication will always work for one whole sector (4 pages).

The following constants are available for this function:

  • NFC_BRICKLET_KEY_A = 0
  • NFC_BRICKLET_KEY_B = 1
pub fn NfcBricklet::reader_write_page(&self, page: u16, data: u8) → Result<(), BrickletRecvTimeoutError>

Writes a maximum of 8192 bytes starting from the given page. How many pages are written depends on the tag type. The page sizes are as follows:

  • Mifare Classic page size: 16 byte
  • NFC Forum Type 1 page size: 8 byte
  • NFC Forum Type 2 page size: 4 byte
  • NFC Forum Type 3 page size: 16 byte
  • NFC Forum Type 4: No pages, page = file selection (CC or NDEF, see below)

The general approach for writing to a tag is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to ReaderRequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. If looking for a specific tag then call NfcBricklet::reader_get_tag_id and check if the expected tag was found, if it was not found got back to step 1
  4. Call NfcBricklet::reader_write_page with page number and data
  5. Wait for state to change to ReaderWritePageReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)

If you use a Mifare Classic tag you have to authenticate a page before you can write to it. See NfcBricklet::reader_authenticate_mifare_classic_page.

NFC Forum Type 4 tags are not organized into pages but different files. We currently support two files: Capability Container file (CC) and NDEF file.

Choose CC by setting page to 3 or NDEF by setting page to 4.

The following constants are available for this function:

  • NFC_BRICKLET_READER_WRITE_TYPE4_CAPABILITY_CONTAINER = 3
  • NFC_BRICKLET_READER_WRITE_TYPE4_NDEF = 4
pub fn NfcBricklet::reader_request_page(&self, page: u16, length: u16) → ConvertingReceiver<()>

Reads a maximum of 8192 bytes starting from the given page and stores them into a buffer. The buffer can then be read out with NfcBricklet::reader_read_page. How many pages are read depends on the tag type. The page sizes are as follows:

  • Mifare Classic page size: 16 byte
  • NFC Forum Type 1 page size: 8 byte
  • NFC Forum Type 2 page size: 4 byte
  • NFC Forum Type 3 page size: 16 byte
  • NFC Forum Type 4: No pages, page = file selection (CC or NDEF, see below)

The general approach for reading a tag is as follows:

  1. Call NfcBricklet::reader_request_tag_id
  2. Wait for state to change to RequestTagIDReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  3. If looking for a specific tag then call NfcBricklet::reader_get_tag_id and check if the expected tag was found, if it was not found got back to step 1
  4. Call NfcBricklet::reader_request_page with page number
  5. Wait for state to change to ReaderRequestPageReady (see NfcBricklet::reader_get_state or NfcBricklet::get_reader_state_changed_callback_receiver callback)
  6. Call NfcBricklet::reader_read_page to retrieve the page from the buffer

If you use a Mifare Classic tag you have to authenticate a page before you can read it. See NfcBricklet::reader_authenticate_mifare_classic_page.

NFC Forum Type 4 tags are not organized into pages but different files. We currently support two files: Capability Container file (CC) and NDEF file.

Choose CC by setting page to 3 or NDEF by setting page to 4.

The following constants are available for this function:

  • NFC_BRICKLET_READER_REQUEST_TYPE4_CAPABILITY_CONTAINER = 3
  • NFC_BRICKLET_READER_REQUEST_TYPE4_NDEF = 4
pub fn NfcBricklet::reader_read_page(&self) → Result<Vec<u8>, BrickletRecvTimeoutError>

Returns the page data from an internal buffer. To fill the buffer with specific pages you have to call NfcBricklet::reader_request_page beforehand.

The buffer can have a size of up to 8192 bytes.

pub fn NfcBricklet::cardemu_get_state(&self) → ConvertingReceiver<CardemuGetState>

Returns the current cardemu state of the NFC Bricklet.

On startup the Bricklet will be in the CardemuInitialization state. The initialization will only take about 20ms. After that it changes to CardemuIdle.

The Bricklet is also reinitialized if the mode is changed, see NfcBricklet::set_mode.

The functions of this Bricklet can be called in the CardemuIdle state and all of the CardemuReady and CardemuError states.

Example: If you call NfcBricklet::cardemu_start_discovery, the state will change to CardemuDiscover until the discovery is finished. Then it will change to either CardemuDiscoverReady if it worked or to CardemuDiscoverError if it didn't.

The same approach is used analogously for the other API functions.

The following constants are available for this function:

  • NFC_BRICKLET_CARDEMU_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_CARDEMU_STATE_IDLE = 128
  • NFC_BRICKLET_CARDEMU_STATE_ERROR = 192
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER = 2
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER_READY = 130
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER_ERROR = 194
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF = 3
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF_READY = 131
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF_ERROR = 195
pub fn NfcBricklet::cardemu_start_discovery(&self) → ConvertingReceiver<()>

Starts the discovery process. If you call this function while a NFC reader device is near to the NFC Bricklet the state will change from CardemuDiscovery to CardemuDiscoveryReady.

If no NFC reader device can be found or if there is an error during discovery the cardemu state will change to CardemuDiscoveryError. In this case you have to restart the discovery process.

If the cardemu state changes to CardemuDiscoveryReady you can start the NDEF message transfer with NfcBricklet::cardemu_write_ndef and NfcBricklet::cardemu_start_transfer.

pub fn NfcBricklet::cardemu_write_ndef(&self, ndef: u8) → Result<(), BrickletRecvTimeoutError>

Writes the NDEF messages that is to be transferred to the NFC peer.

The maximum supported NDEF message size in Cardemu mode is 255 byte.

You can call this function at any time in Cardemu mode. The internal buffer will not be overwritten until you call this function again or change the mode.

pub fn NfcBricklet::cardemu_start_transfer(&self, transfer: u8) → ConvertingReceiver<()>

You can start the transfer of a NDEF message if the cardemu state is CardemuDiscoveryReady.

Before you call this function to start a write transfer, the NDEF message that is to be transferred has to be written via NfcBricklet::cardemu_write_ndef first.

After you call this function the state will change to CardemuTransferNDEF. It will change to CardemuTransferNDEFReady if the transfer was successful or CardemuTransferNDEFError if it wasn't.

The following constants are available for this function:

  • NFC_BRICKLET_CARDEMU_TRANSFER_ABORT = 0
  • NFC_BRICKLET_CARDEMU_TRANSFER_WRITE = 1
pub fn NfcBricklet::p2p_get_state(&self) → ConvertingReceiver<P2pGetState>

Returns the current P2P state of the NFC Bricklet.

On startup the Bricklet will be in the P2PInitialization state. The initialization will only take about 20ms. After that it changes to P2PIdle.

The Bricklet is also reinitialized if the mode is changed, see NfcBricklet::set_mode.

The functions of this Bricklet can be called in the P2PIdle state and all of the P2PReady and P2PError states.

Example: If you call NfcBricklet::p2p_start_discovery, the state will change to P2PDiscover until the discovery is finished. Then it will change to either P2PDiscoverReady* if it worked or to P2PDiscoverError if it didn't.

The same approach is used analogously for the other API functions.

The following constants are available for this function:

  • NFC_BRICKLET_P2P_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_P2P_STATE_IDLE = 128
  • NFC_BRICKLET_P2P_STATE_ERROR = 192
  • NFC_BRICKLET_P2P_STATE_DISCOVER = 2
  • NFC_BRICKLET_P2P_STATE_DISCOVER_READY = 130
  • NFC_BRICKLET_P2P_STATE_DISCOVER_ERROR = 194
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF = 3
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF_READY = 131
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF_ERROR = 195
pub fn NfcBricklet::p2p_start_discovery(&self) → ConvertingReceiver<()>

Starts the discovery process. If you call this function while another NFC P2P enabled device is near to the NFC Bricklet the state will change from P2PDiscovery to P2PDiscoveryReady.

If no NFC P2P enabled device can be found or if there is an error during discovery the P2P state will change to P2PDiscoveryError. In this case you have to restart the discovery process.

If the P2P state changes to P2PDiscoveryReady you can start the NDEF message transfer with NfcBricklet::p2p_start_transfer.

pub fn NfcBricklet::p2p_write_ndef(&self, ndef: u8) → Result<(), BrickletRecvTimeoutError>

Writes the NDEF messages that is to be transferred to the NFC peer.

The maximum supported NDEF message size for P2P transfer is 255 byte.

You can call this function at any time in P2P mode. The internal buffer will not be overwritten until you call this function again, change the mode or use P2P to read an NDEF messages.

pub fn NfcBricklet::p2p_start_transfer(&self, transfer: u8) → ConvertingReceiver<()>

You can start the transfer of a NDEF message if the P2P state is P2PDiscoveryReady.

Before you call this function to start a write transfer, the NDEF message that is to be transferred has to be written via NfcBricklet::p2p_write_ndef first.

After you call this function the P2P state will change to P2PTransferNDEF. It will change to P2PTransferNDEFReady if the transfer was successfull or P2PTransferNDEFError if it wasn't.

If you started a write transfer you are now done. If you started a read transfer you can now use NfcBricklet::p2p_read_ndef to read the NDEF message that was written by the NFC peer.

The following constants are available for this function:

  • NFC_BRICKLET_P2P_TRANSFER_ABORT = 0
  • NFC_BRICKLET_P2P_TRANSFER_WRITE = 1
  • NFC_BRICKLET_P2P_TRANSFER_READ = 2
pub fn NfcBricklet::p2p_read_ndef(&self) → Result<Vec<u8>, BrickletRecvTimeoutError>

Returns the NDEF message that was written by a NFC peer in NFC P2P mode. The maximum NDEF length is 8192 byte.

The NDEF message is ready if you called NfcBricklet::p2p_start_transfer with a read transfer and the P2P state changed to P2PTransferNDEFReady.

Advanced Functions

pub fn NfcBricklet::set_detection_led_config(&self, config: u8) → ConvertingReceiver<()>

Sets the detection LED configuration. By default the LED shows if a card/reader is detected.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is off.

The following constants are available for this function:

  • NFC_BRICKLET_DETECTION_LED_CONFIG_OFF = 0
  • NFC_BRICKLET_DETECTION_LED_CONFIG_ON = 1
  • NFC_BRICKLET_DETECTION_LED_CONFIG_SHOW_HEARTBEAT = 2
  • NFC_BRICKLET_DETECTION_LED_CONFIG_SHOW_DETECTION = 3
pub fn NfcBricklet::get_detection_led_config(&self) → ConvertingReceiver<u8>

Returns the configuration as set by NfcBricklet::set_detection_led_config

The following constants are available for this function:

  • NFC_BRICKLET_DETECTION_LED_CONFIG_OFF = 0
  • NFC_BRICKLET_DETECTION_LED_CONFIG_ON = 1
  • NFC_BRICKLET_DETECTION_LED_CONFIG_SHOW_HEARTBEAT = 2
  • NFC_BRICKLET_DETECTION_LED_CONFIG_SHOW_DETECTION = 3
pub fn NfcBricklet::set_maximum_timeout(&self, timeout: u16) → ConvertingReceiver<()>

Sets the maximum timeout in ms.

This is a global maximum used for all internal state timeouts. The timeouts depend heavily on the used tags etc. For example: If you use a Type 2 tag and you want to detect if it is present, you have to use NfcBricklet::reader_request_tag_id and wait for the state to change to either the error state or the ready state.

With the default configuration this takes 2-3 seconds. By setting the maximum timeout to 100ms you can reduce this time to ~150-200ms. For Type 2 this would also still work with a 20ms timeout (a Type 2 tag answers usually within 10ms). A type 4 tag can take up to 500ms in our tests.

If you need a fast response time to discover if a tag is present or not you can find a good timeout value by trial and error for your specific tag.

By default we use a very conservative timeout, to be sure that any Tag can always answer in time.

Default timeout: 2000ms.

New in version 2.0.1 (Plugin).

pub fn NfcBricklet::get_maximum_timeout(&self) → ConvertingReceiver<u16>

Returns the timeout as set by NfcBricklet::set_maximum_timeout

New in version 2.0.1 (Plugin).

pub fn NfcBricklet::get_api_version(&self) → [u8; 3]

Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

pub fn NfcBricklet::get_response_expected(&mut self, function_id: u8) → bool

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by NfcBricklet::set_response_expected. For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

  • NFC_BRICKLET_FUNCTION_SET_MODE = 1
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_TAG_ID = 3
  • NFC_BRICKLET_FUNCTION_READER_WRITE_NDEF = 6
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_NDEF = 7
  • NFC_BRICKLET_FUNCTION_READER_AUTHENTICATE_MIFARE_CLASSIC_PAGE = 9
  • NFC_BRICKLET_FUNCTION_READER_WRITE_PAGE = 10
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_PAGE = 11
  • NFC_BRICKLET_FUNCTION_CARDEMU_START_DISCOVERY = 15
  • NFC_BRICKLET_FUNCTION_CARDEMU_WRITE_NDEF = 16
  • NFC_BRICKLET_FUNCTION_CARDEMU_START_TRANSFER = 17
  • NFC_BRICKLET_FUNCTION_P2P_START_DISCOVERY = 20
  • NFC_BRICKLET_FUNCTION_P2P_WRITE_NDEF = 21
  • NFC_BRICKLET_FUNCTION_P2P_START_TRANSFER = 22
  • NFC_BRICKLET_FUNCTION_SET_DETECTION_LED_CONFIG = 25
  • NFC_BRICKLET_FUNCTION_SET_MAXIMUM_TIMEOUT = 27
  • NFC_BRICKLET_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • NFC_BRICKLET_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • NFC_BRICKLET_FUNCTION_RESET = 243
  • NFC_BRICKLET_FUNCTION_WRITE_UID = 248
pub fn NfcBricklet::set_response_expected(&mut self, function_id: u8, response_expected: bool) → ()

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

  • NFC_BRICKLET_FUNCTION_SET_MODE = 1
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_TAG_ID = 3
  • NFC_BRICKLET_FUNCTION_READER_WRITE_NDEF = 6
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_NDEF = 7
  • NFC_BRICKLET_FUNCTION_READER_AUTHENTICATE_MIFARE_CLASSIC_PAGE = 9
  • NFC_BRICKLET_FUNCTION_READER_WRITE_PAGE = 10
  • NFC_BRICKLET_FUNCTION_READER_REQUEST_PAGE = 11
  • NFC_BRICKLET_FUNCTION_CARDEMU_START_DISCOVERY = 15
  • NFC_BRICKLET_FUNCTION_CARDEMU_WRITE_NDEF = 16
  • NFC_BRICKLET_FUNCTION_CARDEMU_START_TRANSFER = 17
  • NFC_BRICKLET_FUNCTION_P2P_START_DISCOVERY = 20
  • NFC_BRICKLET_FUNCTION_P2P_WRITE_NDEF = 21
  • NFC_BRICKLET_FUNCTION_P2P_START_TRANSFER = 22
  • NFC_BRICKLET_FUNCTION_SET_DETECTION_LED_CONFIG = 25
  • NFC_BRICKLET_FUNCTION_SET_MAXIMUM_TIMEOUT = 27
  • NFC_BRICKLET_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • NFC_BRICKLET_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • NFC_BRICKLET_FUNCTION_RESET = 243
  • NFC_BRICKLET_FUNCTION_WRITE_UID = 248
pub fn NfcBricklet::set_response_expected_all(&mut self, response_expected: bool) → ()

Changes the response expected flag for all setter and callback configuration functions of this device at once.

pub fn NfcBricklet::get_spitfp_error_count(&self) → ConvertingReceiver<SpitfpErrorCount>

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

  • ACK checksum errors,
  • message checksum errors,
  • framing errors and
  • overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

pub fn NfcBricklet::set_bootloader_mode(&self, mode: u8) → ConvertingReceiver<u8>

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

  • NFC_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • NFC_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • NFC_BRICKLET_BOOTLOADER_STATUS_OK = 0
  • NFC_BRICKLET_BOOTLOADER_STATUS_INVALID_MODE = 1
  • NFC_BRICKLET_BOOTLOADER_STATUS_NO_CHANGE = 2
  • NFC_BRICKLET_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • NFC_BRICKLET_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • NFC_BRICKLET_BOOTLOADER_STATUS_CRC_MISMATCH = 5
pub fn NfcBricklet::get_bootloader_mode(&self) → ConvertingReceiver<u8>

Returns the current bootloader mode, see NfcBricklet::set_bootloader_mode.

The following constants are available for this function:

  • NFC_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • NFC_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • NFC_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
pub fn NfcBricklet::set_write_firmware_pointer(&self, pointer: u32) → ConvertingReceiver<()>

Sets the firmware pointer for NfcBricklet::write_firmware. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

pub fn NfcBricklet::write_firmware(&self, data: [u8; 64]) → ConvertingReceiver<u8>

Writes 64 Bytes of firmware at the position as written by NfcBricklet::set_write_firmware_pointer before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

pub fn NfcBricklet::set_status_led_config(&self, config: u8) → ConvertingReceiver<()>

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

  • NFC_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • NFC_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • NFC_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • NFC_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn NfcBricklet::get_status_led_config(&self) → ConvertingReceiver<u8>

Returns the configuration as set by NfcBricklet::set_status_led_config

The following constants are available for this function:

  • NFC_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • NFC_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • NFC_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • NFC_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn NfcBricklet::get_chip_temperature(&self) → ConvertingReceiver<i16>

Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

pub fn NfcBricklet::reset(&self) → ConvertingReceiver<()>

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

pub fn NfcBricklet::write_uid(&self, uid: u32) → ConvertingReceiver<()>

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

pub fn NfcBricklet::read_uid(&self) → ConvertingReceiver<u32>

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

pub fn NfcBricklet::get_identity(&self) → ConvertingReceiver<Identity>

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c' or 'd'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding get_*_callback_receiver function, which returns a receiver for callback events.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

pub fn NfcBricklet::get_reader_state_changed_callback_receiver(&self) → ConvertingCallbackReceiver<ReaderStateChangedEvent>

Receivers created with this function receive Reader State Changed events.

This callback is called if the reader state of the NFC Bricklet changes. See NfcBricklet::reader_get_state for more information about the possible states.

The following constants are available for this function:

  • NFC_BRICKLET_READER_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_READER_STATE_IDLE = 128
  • NFC_BRICKLET_READER_STATE_ERROR = 192
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID = 2
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_READY = 130
  • NFC_BRICKLET_READER_STATE_REQUEST_TAG_ID_ERROR = 194
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE = 3
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE_READY = 131
  • NFC_BRICKLET_READER_STATE_AUTHENTICATE_MIFARE_CLASSIC_PAGE_ERROR = 195
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE = 4
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE_READY = 132
  • NFC_BRICKLET_READER_STATE_WRITE_PAGE_ERROR = 196
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE = 5
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE_READY = 133
  • NFC_BRICKLET_READER_STATE_REQUEST_PAGE_ERROR = 197
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF = 6
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF_READY = 134
  • NFC_BRICKLET_READER_STATE_WRITE_NDEF_ERROR = 198
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF = 7
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF_READY = 135
  • NFC_BRICKLET_READER_STATE_REQUEST_NDEF_ERROR = 199
pub fn NfcBricklet::get_cardemu_state_changed_callback_receiver(&self) → ConvertingCallbackReceiver<CardemuStateChangedEvent>

Receivers created with this function receive Cardemu State Changed events.

This callback is called if the cardemu state of the NFC Bricklet changes. See NfcBricklet::cardemu_get_state for more information about the possible states.

The following constants are available for this function:

  • NFC_BRICKLET_CARDEMU_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_CARDEMU_STATE_IDLE = 128
  • NFC_BRICKLET_CARDEMU_STATE_ERROR = 192
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER = 2
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER_READY = 130
  • NFC_BRICKLET_CARDEMU_STATE_DISCOVER_ERROR = 194
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF = 3
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF_READY = 131
  • NFC_BRICKLET_CARDEMU_STATE_TRANSFER_NDEF_ERROR = 195
pub fn NfcBricklet::get_p2p_state_changed_callback_receiver(&self) → ConvertingCallbackReceiver<P2pStateChangedEvent>

Receivers created with this function receive P2P State Changed events.

This callback is called if the P2P state of the NFC Bricklet changes. See NfcBricklet::p2p_get_state for more information about the possible states.

The following constants are available for this function:

  • NFC_BRICKLET_P2P_STATE_INITIALIZATION = 0
  • NFC_BRICKLET_P2P_STATE_IDLE = 128
  • NFC_BRICKLET_P2P_STATE_ERROR = 192
  • NFC_BRICKLET_P2P_STATE_DISCOVER = 2
  • NFC_BRICKLET_P2P_STATE_DISCOVER_READY = 130
  • NFC_BRICKLET_P2P_STATE_DISCOVER_ERROR = 194
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF = 3
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF_READY = 131
  • NFC_BRICKLET_P2P_STATE_TRANSFER_NDEF_ERROR = 195

Constants

NfcBricklet::DEVICE_IDENTIFIER

This constant is used to identify a NFC Bricklet.

The NfcBricklet::get_identity function and the IpConnection::get_enumerate_callback_receiver callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

NfcBricklet::DEVICE_DISPLAY_NAME

This constant represents the human readable name of a NFC Bricklet.