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@johntalton/st25dv

v1.2.1

Published

![CI](https://github.com/johntalton/st25dv/workflows/CI/badge.svg)

Readme

ST25DV

CI

Dynamic NFC/RFID tag javascript driver over abstracted I2CBus implementation.

Obligatory Adafruit

Multiple Address

The ST25DV presents on the bus as two (2) unique addresses (typically 0x53 and 0x57). This split corresponds to the devices "user" and "system" interaction spaces.

That is, to access the main persistent configuration settings the System area need to be accessed, while most operational command are in the user area.

This library provides both ST25DVUser and ST25DVSystem classes for abstracting those interactions (as well as a convenance ST25DV wrapper class).

The choice to allow setting and interacting with different classes with separate I2CAddressedBus abstraction is provided to allow for a range of configurations and interaction when the underlining I2CBus implementations may very.

Example

Direct system device access

The following example shows access to the System configuration area.

const bus = /* I2CBus concrete from your choice of sources */
const abus = I2CAddressedBus.from(bus, DEFAULT_ST25DV_SYSTEM_ADDRESS)
const device = ST25DVSystem.from(abus)

const uid = await device.getUID()

Wrapper class

Using the same example as above while utalizing teh wrapper ST25DV class

const bus = /* again, some I2CBus, such as the MCP2221  */
const abusUser = I2CAddressedBus.from(bus, DEFAULT_ST25DV_USER_ADDRESS)
const abusSystem = I2CAddressedBus.from(bus, DEFAULT_ST25DV_SYSTEM_ADDRESS)
const device = ST25DV.from(abusUser, abusSystem)

const uid = await device.system.getUID()

Password protected configuration

In order to write to the majority of the configuration, a I²C "password" must first be sent to the device to "open a secure session". This can be configured for a range of configuration and user areas.