Struct stm32wlxx_hal::rtc::Rtc

source ·

pub struct Rtc { /* private fields */ }

Available on crate feature chrono only.

Expand description

Real-time clock driver.

Implementations§

source §

impl Rtc

source

pub fn new(rtc: RTC, clk: Clk, pwr: &mut PWR, rcc: &mut RCC) -> Rtc

Create a new real-time clock driver.

This will not setup the source clock.

Safety

This function could be considered unsafe because it is not a pure function. The RTC is in the backup domain; system resets will not reset the RTC. You are responsible for resetting the backup domain if required.

Panics

(debug) clock source is not ready.

Example

LSE clock source (this depends on HW, example valid for NUCLEO board):

use stm32wlxx_hal::{
    pac,
    rcc::pulse_reset_backup_domain,
    rtc::{Clk, Rtc},
};

let mut dp: pac::Peripherals = pac::Peripherals::take().unwrap();

unsafe { pulse_reset_backup_domain(&mut dp.RCC, &mut dp.PWR) };
dp.PWR.cr1.modify(|_, w| w.dbp().enabled());
dp.RCC.bdcr.modify(|_, w| w.lseon().on());
while dp.RCC.bdcr.read().lserdy().is_not_ready() {}

let rtc: Rtc = Rtc::new(dp.RTC, Clk::Lse, &mut dp.PWR, &mut dp.RCC);

LSI clock source:

use stm32wlxx_hal::{
    pac,
    rcc::{enable_lsi, pulse_reset_backup_domain},
    rtc::{Clk, Rtc},
};

let mut dp: pac::Peripherals = pac::Peripherals::take().unwrap();

unsafe { pulse_reset_backup_domain(&mut dp.RCC, &mut dp.PWR) };
enable_lsi(&mut dp.RCC);

let rtc: Rtc = Rtc::new(dp.RTC, Clk::Lsi, &mut dp.PWR, &mut dp.RCC);

HSE clock source (this depends on your hardware):

use stm32wlxx_hal::{
    pac,
    rcc::pulse_reset_backup_domain,
    rtc::{Clk, Rtc},
};

let mut dp: pac::Peripherals = pac::Peripherals::take().unwrap();

unsafe { pulse_reset_backup_domain(&mut dp.RCC, &mut dp.PWR) };
dp.RCC
    .cr
    .modify(|_, w| w.hseon().enabled().hsebyppwr().vddtcxo());
while dp.RCC.cr.read().hserdy().is_not_ready() {}

let rtc: Rtc = Rtc::new(dp.RTC, Clk::Hse, &mut dp.PWR, &mut dp.RCC);

source

pub unsafe fn renew(rtc: RTC, pwr: &mut PWR, rcc: &mut RCC) -> Rtc

Create a new real-time clock driver preserving backup domain values.

Unlike new this will enable the LSE clock source if not already enabled. This function assumes the LSE clock source will be used because it is the only clock source that is preserved in the shutdown mode.

The RTC calendar may not be initialized, this can occur if this function is called after power loss or after a backup domain reset.

Safety

This function relies on global hardware state in the backup domain. The backup domain is not reset with normal system resets. Reset the backup domain before calling this function if determinism is required.

source

pub fn hz(rcc: &RCC) -> u32

Source clock frequency in hertz.

source

pub fn status() -> R

Read the RTC status (interrupt) register.

source

pub fn masked_status() -> R

Read the RTC masked status (interrupt) register.

source

pub fn clear_status(mask: u32)

Clear status (interrupt) flags.

Status flag masks can be found in stat.

source

pub fn set_date_time(&mut self, date_time: NaiveDateTime)

Set the date and time.

The value will take some duration to apply after this function returns:

LPCAL=0: the counting restarts after 4 RTCCLK clock cycles
LPCAL=1: the counting restarts after up to 2 RTCCLK + 1 ck_apre

Panics

Year is greater than or equal to 2100.
Year is less than 2000.
Backup domain write protection is enabled.

source

pub fn calendar_initialized(&self) -> Option<()>

Returns None if the calendar is uninitialized.

source

pub fn calibrate_lp(&mut self, calibration: i16)

Calibrate the RTC using the low-power mode.

This does not poll for completion, use recalibration_pending if you need to wait for completion.

The calibration argument is in units of 0.9537 ppm. The calibration range is -487.1 ppm to +488.5 ppm (-511 to 512), values outside of this range will saturate.

source