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Rust DS1307 Real-Time Clock Driver

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This is a platform agnostic Rust driver for the DS1307 real-time clock, based on the embedded-hal traits.

This driver allows you to:

  • Read and set date and time in 12-hour and 24-hour format. See: datetime
  • Enable and disable the real-time clock. See: set_running
  • Read and write user RAM. See: read_ram
  • Control square-wave output. See: enable_square_wave_output

Introductory blog post

The device

The DS1307 serial real-time clock (RTC) is a low-power, full binary-coded decimal (BCD) clock/calendar plus 56 bytes of NV SRAM. Address and data are transferred serially through an I2C, bidirectional bus.

The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The end of the month date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with AM/PM indicator.

The DS1307 has a built-in power-sense circuit that detects power failures and automatically switches to the backup supply. Timekeeping operation continues while the part operates from the backup supply.

Datasheet: DS1307


To use this driver, import this crate and an embedded_hal implementation, then instantiate the device.

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

use ds1307::{DateTimeAccess, Ds1307, NaiveDate};
use linux_embedded_hal::I2cdev;

fn main() {
    let dev = I2cdev::new("/dev/i2c-1").unwrap();
    let mut rtc = Ds1307::new(dev);
    let datetime = NaiveDate::from_ymd_opt(2022, 1, 2)
        .and_hms_opt(19, 59, 58)
    // ...
    let datetime = rtc.datetime().unwrap();
    // This will print something like: 2022-01-02 19:59:58

Minimum Supported Rust Version (MSRV)

This crate is guaranteed to compile on stable Rust 1.62 and up. It might compile with older versions but that may change in any new patch release.


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


Licensed under either of

at your option.


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.


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