Rust 24x EEPROM Driver

This is a platform agnostic Rust driver for the 24x series serial EEPROM, based on the embedded-hal traits.

This driver allows you to:

• Read a single byte from a memory address. See: read_byte().
• Read a byte array starting on a memory address. See: read_data().
• Read the current memory address (please read notes). See: read_current_address().
• Write a byte to a memory address. See: write_byte().
• Write a byte array (up to a memory page) to a memory address. See: write_page().
• Read CSx-variant devices' factory-programmed unique serial. See: read_unique_serial().
• Use the device in generic code via the Eeprom24xTrait.

Can be used at least with the devices listed below.

Introductory blog post

The devices

These devices provides a number of bits of serial electrically erasable and programmable read only memory (EEPROM) organized as a number of words of 8 bits each. The devices' cascadable feature allows up to 8 devices to share a common 2-wire bus. The devices are optimized for use in many industrial and commercial applications where low power and low voltage operation are essential.

Device	Memory bits	8-bit words	Page size	Datasheet
24x00	128 bits	16	N/A	24C00
24x01	1 Kbit	128	8 bytes	AT24C01
M24x01	1 Kbit	128	16 bytes	M24C01
24x02	2 Kbit	256	8 bytes	AT24C02
M24x02	2 Kbit	256	16 bytes	M24C02
24x04	4 Kbit	512	16 bytes	AT24C04
24x08	8 Kbit	1,024	16 bytes	AT24C08
24x16	16 Kbit	2,048	16 bytes	AT24C16
24x32	32 Kbit	4,096	32 bytes	AT24C32
24x64	64 Kbit	8,192	32 bytes	AT24C64
24x128	128 Kbit	16,384	64 bytes	AT24C128
24x256	256 Kbit	32,768	64 bytes	AT24C256
24x512	512 Kbit	65,536	128 bytes	AT24C512
24xM01	1 Mbit	131,072	256 bytes	AT24CM01
24xM02	2 Mbit	262,144	256 bytes	AT24CM02

Usage

To use this driver, import this crate and an embedded_hal implementation, then instantiate the appropriate device. In the following examples an instance of the device AT24C256 will be created as an example. Other devices can be created with similar methods like: Eeprom24x::new_24x64(...).

Please find additional examples using hardware in this repository: driver-examples

use eeprom24x::{Eeprom24x, SlaveAddr};
use embedded_hal::blocking::delay::DelayMs;
use linux_embedded_hal::{Delay, I2cdev};

fn main() {
    let dev = I2cdev::new("/dev/i2c-1").unwrap();
    let address = SlaveAddr::default();
    let mut eeprom = Eeprom24x::new_24x256(dev, address);
    let memory_address = 0x1234;
    let data = 0xAB;

    eeprom.write_byte(memory_address, data).unwrap();

    Delay.delay_ms(5u16);

    let read_data = eeprom.read_byte(memory_address).unwrap();

    println!(
        "Read memory address: {}, retrieved content: {}",
        memory_address, &read_data
    );

    let _dev = eeprom.destroy(); // Get the I2C device back
}

Features

defmt-03

To enable defmt (version 0.3.x) support, when specifying the dependency on eeprom24x, add the feature "defmt-03".

[dependencies]
eeprom24x = { version = "0.7.2", features = ["defmt-03"] }

Support

For questions, issues, feature requests, and other changes, please file an issue in the github project.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contributing

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.