circuitpython/ports/stm32/rtc.c
2020-04-05 15:02:06 +10:00

772 lines
26 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2013, 2014 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdio.h>
#include "py/runtime.h"
#include "extint.h"
#include "rtc.h"
#include "irq.h"
#if defined(STM32WB)
#define RCC_CSR_LSION RCC_CSR_LSI1ON
#define RCC_FLAG_LSIRDY RCC_FLAG_LSI1RDY
#define RCC_OSCILLATORTYPE_LSI RCC_OSCILLATORTYPE_LSI1
#define __HAL_RCC_LSI_ENABLE __HAL_RCC_LSI1_ENABLE
#define __HAL_RCC_LSI_DISABLE __HAL_RCC_LSI1_DISABLE
#endif
/// \moduleref pyb
/// \class RTC - real time clock
///
/// The RTC is and independent clock that keeps track of the date
/// and time.
///
/// Example usage:
///
/// rtc = pyb.RTC()
/// rtc.datetime((2014, 5, 1, 4, 13, 0, 0, 0))
/// print(rtc.datetime())
RTC_HandleTypeDef RTCHandle;
// rtc_info indicates various things about RTC startup
// it's a bit of a hack at the moment
static mp_uint_t rtc_info;
// Note: LSI is around (32KHz), these dividers should work either way
// ck_spre(1Hz) = RTCCLK(LSE) /(uwAsynchPrediv + 1)*(uwSynchPrediv + 1)
// modify RTC_ASYNCH_PREDIV & RTC_SYNCH_PREDIV in board/<BN>/mpconfigport.h to change sub-second ticks
// default is 3906.25 us, min is ~30.52 us (will increase Ivbat by ~500nA)
#ifndef RTC_ASYNCH_PREDIV
#define RTC_ASYNCH_PREDIV (0x7f)
#endif
#ifndef RTC_SYNCH_PREDIV
#define RTC_SYNCH_PREDIV (0x00ff)
#endif
STATIC HAL_StatusTypeDef PYB_RTC_Init(RTC_HandleTypeDef *hrtc);
STATIC void PYB_RTC_MspInit_Kick(RTC_HandleTypeDef *hrtc, bool rtc_use_lse, bool rtc_use_byp);
STATIC HAL_StatusTypeDef PYB_RTC_MspInit_Finalise(RTC_HandleTypeDef *hrtc);
STATIC void RTC_CalendarConfig(void);
#if MICROPY_HW_RTC_USE_LSE || MICROPY_HW_RTC_USE_BYPASS
STATIC bool rtc_use_lse = true;
#else
STATIC bool rtc_use_lse = false;
#endif
STATIC uint32_t rtc_startup_tick;
STATIC bool rtc_need_init_finalise = false;
#if defined(STM32L0)
#define BDCR CSR
#define RCC_BDCR_RTCEN RCC_CSR_RTCEN
#define RCC_BDCR_RTCSEL RCC_CSR_RTCSEL
#define RCC_BDCR_RTCSEL_0 RCC_CSR_RTCSEL_0
#define RCC_BDCR_RTCSEL_1 RCC_CSR_RTCSEL_1
#define RCC_BDCR_LSEON RCC_CSR_LSEON
#define RCC_BDCR_LSERDY RCC_CSR_LSERDY
#define RCC_BDCR_LSEBYP RCC_CSR_LSEBYP
#endif
void rtc_init_start(bool force_init) {
RTCHandle.Instance = RTC;
/* Configure RTC prescaler and RTC data registers */
/* RTC configured as follow:
- Hour Format = Format 24
- Asynch Prediv = Value according to source clock
- Synch Prediv = Value according to source clock
- OutPut = Output Disable
- OutPutPolarity = High Polarity
- OutPutType = Open Drain */
RTCHandle.Init.HourFormat = RTC_HOURFORMAT_24;
RTCHandle.Init.AsynchPrediv = RTC_ASYNCH_PREDIV;
RTCHandle.Init.SynchPrediv = RTC_SYNCH_PREDIV;
RTCHandle.Init.OutPut = RTC_OUTPUT_DISABLE;
RTCHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
RTCHandle.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
rtc_need_init_finalise = false;
if (!force_init) {
uint32_t bdcr = RCC->BDCR;
if ((bdcr & (RCC_BDCR_RTCEN | RCC_BDCR_RTCSEL | RCC_BDCR_LSEON | RCC_BDCR_LSERDY))
== (RCC_BDCR_RTCEN | RCC_BDCR_RTCSEL_0 | RCC_BDCR_LSEON | RCC_BDCR_LSERDY)) {
// LSE is enabled & ready --> no need to (re-)init RTC
// remove Backup Domain write protection
HAL_PWR_EnableBkUpAccess();
// Clear source Reset Flag
__HAL_RCC_CLEAR_RESET_FLAGS();
// provide some status information
rtc_info |= 0x40000 | (RCC->BDCR & 7) | (RCC->CSR & 3) << 8;
return;
} else if ((bdcr & (RCC_BDCR_RTCEN | RCC_BDCR_RTCSEL))
== (RCC_BDCR_RTCEN | RCC_BDCR_RTCSEL_1)) {
// LSI configured as the RTC clock source --> no need to (re-)init RTC
// remove Backup Domain write protection
HAL_PWR_EnableBkUpAccess();
// Clear source Reset Flag
__HAL_RCC_CLEAR_RESET_FLAGS();
// Turn the LSI on (it may need this even if the RTC is running)
RCC->CSR |= RCC_CSR_LSION;
// provide some status information
rtc_info |= 0x80000 | (RCC->BDCR & 7) | (RCC->CSR & 3) << 8;
return;
}
}
rtc_startup_tick = HAL_GetTick();
rtc_info = 0x3f000000 | (rtc_startup_tick & 0xffffff);
PYB_RTC_MspInit_Kick(&RTCHandle, rtc_use_lse, MICROPY_HW_RTC_USE_BYPASS);
}
void rtc_init_finalise() {
if (!rtc_need_init_finalise) {
return;
}
rtc_info = 0;
while (PYB_RTC_Init(&RTCHandle) != HAL_OK) {
if (rtc_use_lse) {
#if MICROPY_HW_RTC_USE_BYPASS
if (RCC->BDCR & RCC_BDCR_LSEBYP) {
// LSEBYP failed, fallback to LSE non-bypass
rtc_info |= 0x02000000;
} else
#endif
{
// LSE failed, fallback to LSI
rtc_use_lse = false;
rtc_info |= 0x01000000;
}
rtc_startup_tick = HAL_GetTick();
PYB_RTC_MspInit_Kick(&RTCHandle, rtc_use_lse, false);
HAL_PWR_EnableBkUpAccess();
RTCHandle.State = HAL_RTC_STATE_RESET;
} else {
// init error
rtc_info |= 0xffff; // indicate error
return;
}
}
// RTC started successfully
rtc_info = 0x20000000;
// record if LSE or LSI is used
rtc_info |= (rtc_use_lse << 28);
// record how long it took for the RTC to start up
rtc_info |= (HAL_GetTick() - rtc_startup_tick) & 0xffff;
// fresh reset; configure RTC Calendar
RTC_CalendarConfig();
#if defined(STM32L4) || defined(STM32WB)
if (__HAL_RCC_GET_FLAG(RCC_FLAG_BORRST) != RESET) {
#else
if (__HAL_RCC_GET_FLAG(RCC_FLAG_PORRST) != RESET) {
#endif
// power on reset occurred
rtc_info |= 0x10000;
}
if (__HAL_RCC_GET_FLAG(RCC_FLAG_PINRST) != RESET) {
// external reset occurred
rtc_info |= 0x20000;
}
// Clear source Reset Flag
__HAL_RCC_CLEAR_RESET_FLAGS();
rtc_need_init_finalise = false;
}
STATIC HAL_StatusTypeDef PYB_RCC_OscConfig(RCC_OscInitTypeDef *RCC_OscInitStruct) {
/*------------------------------ LSI Configuration -------------------------*/
if ((RCC_OscInitStruct->OscillatorType & RCC_OSCILLATORTYPE_LSI) == RCC_OSCILLATORTYPE_LSI) {
// Check the LSI State
if (RCC_OscInitStruct->LSIState != RCC_LSI_OFF) {
// Enable the Internal Low Speed oscillator (LSI).
__HAL_RCC_LSI_ENABLE();
} else {
// Disable the Internal Low Speed oscillator (LSI).
__HAL_RCC_LSI_DISABLE();
}
}
/*------------------------------ LSE Configuration -------------------------*/
if ((RCC_OscInitStruct->OscillatorType & RCC_OSCILLATORTYPE_LSE) == RCC_OSCILLATORTYPE_LSE) {
#if !defined(STM32H7) && !defined(STM32WB)
// Enable Power Clock
__HAL_RCC_PWR_CLK_ENABLE();
#endif
// Enable access to the backup domain
HAL_PWR_EnableBkUpAccess();
uint32_t tickstart = HAL_GetTick();
#if defined(STM32F7) || defined(STM32L4) || defined(STM32H7) || defined(STM32WB)
//__HAL_RCC_PWR_CLK_ENABLE();
// Enable write access to Backup domain
//PWR->CR1 |= PWR_CR1_DBP;
// Wait for Backup domain Write protection disable
while ((PWR->CR1 & PWR_CR1_DBP) == RESET) {
if (HAL_GetTick() - tickstart > RCC_DBP_TIMEOUT_VALUE) {
return HAL_TIMEOUT;
}
}
#else
// Enable write access to Backup domain
//PWR->CR |= PWR_CR_DBP;
// Wait for Backup domain Write protection disable
while ((PWR->CR & PWR_CR_DBP) == RESET) {
if (HAL_GetTick() - tickstart > RCC_DBP_TIMEOUT_VALUE) {
return HAL_TIMEOUT;
}
}
#endif
#if MICROPY_HW_RTC_USE_BYPASS
// If LSEBYP is enabled and new state is non-bypass then disable LSEBYP
if (RCC_OscInitStruct->LSEState == RCC_LSE_ON && (RCC->BDCR & RCC_BDCR_LSEBYP)) {
CLEAR_BIT(RCC->BDCR, RCC_BDCR_LSEON);
while (RCC->BDCR & RCC_BDCR_LSERDY) {
}
CLEAR_BIT(RCC->BDCR, RCC_BDCR_LSEBYP);
}
#endif
// Set the new LSE configuration
__HAL_RCC_LSE_CONFIG(RCC_OscInitStruct->LSEState);
}
return HAL_OK;
}
STATIC HAL_StatusTypeDef PYB_RTC_Init(RTC_HandleTypeDef *hrtc) {
// Check the RTC peripheral state
if (hrtc == NULL) {
return HAL_ERROR;
}
if (hrtc->State == HAL_RTC_STATE_RESET) {
// Allocate lock resource and initialize it
hrtc->Lock = HAL_UNLOCKED;
// Initialize RTC MSP
if (PYB_RTC_MspInit_Finalise(hrtc) != HAL_OK) {
return HAL_ERROR;
}
}
// Set RTC state
hrtc->State = HAL_RTC_STATE_BUSY;
// Disable the write protection for RTC registers
__HAL_RTC_WRITEPROTECTION_DISABLE(hrtc);
// Set Initialization mode
if (RTC_EnterInitMode(hrtc) != HAL_OK) {
// Enable the write protection for RTC registers
__HAL_RTC_WRITEPROTECTION_ENABLE(hrtc);
// Set RTC state
hrtc->State = HAL_RTC_STATE_ERROR;
return HAL_ERROR;
} else {
// Clear RTC_CR FMT, OSEL and POL Bits
hrtc->Instance->CR &= ((uint32_t) ~(RTC_CR_FMT | RTC_CR_OSEL | RTC_CR_POL));
// Set RTC_CR register
hrtc->Instance->CR |= (uint32_t)(hrtc->Init.HourFormat | hrtc->Init.OutPut | hrtc->Init.OutPutPolarity);
// Configure the RTC PRER
hrtc->Instance->PRER = (uint32_t)(hrtc->Init.SynchPrediv);
hrtc->Instance->PRER |= (uint32_t)(hrtc->Init.AsynchPrediv << 16);
// Exit Initialization mode
hrtc->Instance->ISR &= (uint32_t) ~RTC_ISR_INIT;
#if defined(STM32L0) || defined(STM32L4) || defined(STM32H7) || defined(STM32WB)
hrtc->Instance->OR &= (uint32_t) ~RTC_OR_ALARMOUTTYPE;
hrtc->Instance->OR |= (uint32_t)(hrtc->Init.OutPutType);
#elif defined(STM32F7)
hrtc->Instance->OR &= (uint32_t) ~RTC_OR_ALARMTYPE;
hrtc->Instance->OR |= (uint32_t)(hrtc->Init.OutPutType);
#else
hrtc->Instance->TAFCR &= (uint32_t) ~RTC_TAFCR_ALARMOUTTYPE;
hrtc->Instance->TAFCR |= (uint32_t)(hrtc->Init.OutPutType);
#endif
// Enable the write protection for RTC registers
__HAL_RTC_WRITEPROTECTION_ENABLE(hrtc);
// Set RTC state
hrtc->State = HAL_RTC_STATE_READY;
return HAL_OK;
}
}
STATIC void PYB_RTC_MspInit_Kick(RTC_HandleTypeDef *hrtc, bool rtc_use_lse, bool rtc_use_byp) {
/* To change the source clock of the RTC feature (LSE, LSI), You have to:
- Enable the power clock using __PWR_CLK_ENABLE()
- Enable write access using HAL_PWR_EnableBkUpAccess() function before to
configure the RTC clock source (to be done once after reset).
- Reset the Back up Domain using __HAL_RCC_BACKUPRESET_FORCE() and
__HAL_RCC_BACKUPRESET_RELEASE().
- Configure the needed RTc clock source */
// RTC clock source uses LSE (external crystal) only if relevant
// configuration variable is set. Otherwise it uses LSI (internal osc).
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
#if MICROPY_HW_RTC_USE_BYPASS
if (rtc_use_byp) {
RCC_OscInitStruct.LSEState = RCC_LSE_BYPASS;
RCC_OscInitStruct.LSIState = RCC_LSI_OFF;
} else
#endif
if (rtc_use_lse) {
RCC_OscInitStruct.LSEState = RCC_LSE_ON;
RCC_OscInitStruct.LSIState = RCC_LSI_OFF;
} else {
RCC_OscInitStruct.LSEState = RCC_LSE_OFF;
RCC_OscInitStruct.LSIState = RCC_LSI_ON;
}
PYB_RCC_OscConfig(&RCC_OscInitStruct);
// now ramp up osc. in background and flag calendear init needed
rtc_need_init_finalise = true;
}
#ifndef MICROPY_HW_RTC_LSE_TIMEOUT_MS
#define MICROPY_HW_RTC_LSE_TIMEOUT_MS 1000 // ST docs spec 2000 ms LSE startup, seems to be too pessimistic
#endif
#ifndef MICROPY_HW_RTC_LSI_TIMEOUT_MS
#define MICROPY_HW_RTC_LSI_TIMEOUT_MS 500 // this is way too pessimistic, typ. < 1ms
#endif
#ifndef MICROPY_HW_RTC_BYP_TIMEOUT_MS
#define MICROPY_HW_RTC_BYP_TIMEOUT_MS 150
#endif
STATIC HAL_StatusTypeDef PYB_RTC_MspInit_Finalise(RTC_HandleTypeDef *hrtc) {
// we already had a kick so now wait for the corresponding ready state...
if (rtc_use_lse) {
// we now have to wait for LSE ready or timeout
uint32_t timeout = MICROPY_HW_RTC_LSE_TIMEOUT_MS;
#if MICROPY_HW_RTC_USE_BYPASS
if (RCC->BDCR & RCC_BDCR_LSEBYP) {
timeout = MICROPY_HW_RTC_BYP_TIMEOUT_MS;
}
#endif
uint32_t tickstart = rtc_startup_tick;
while (__HAL_RCC_GET_FLAG(RCC_FLAG_LSERDY) == RESET) {
if ((HAL_GetTick() - tickstart) > timeout) {
return HAL_TIMEOUT;
}
}
} else {
// we now have to wait for LSI ready or timeout
uint32_t tickstart = rtc_startup_tick;
while (__HAL_RCC_GET_FLAG(RCC_FLAG_LSIRDY) == RESET) {
if ((HAL_GetTick() - tickstart) > MICROPY_HW_RTC_LSI_TIMEOUT_MS) {
return HAL_TIMEOUT;
}
}
}
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC;
if (rtc_use_lse) {
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
} else {
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSI;
}
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK) {
//Error_Handler();
return HAL_ERROR;
}
// enable RTC peripheral clock
__HAL_RCC_RTC_ENABLE();
return HAL_OK;
}
STATIC void RTC_CalendarConfig(void) {
// set the date to 1st Jan 2015
RTC_DateTypeDef date;
date.Year = 15;
date.Month = 1;
date.Date = 1;
date.WeekDay = RTC_WEEKDAY_THURSDAY;
if (HAL_RTC_SetDate(&RTCHandle, &date, RTC_FORMAT_BIN) != HAL_OK) {
// init error
return;
}
// set the time to 00:00:00
RTC_TimeTypeDef time;
time.Hours = 0;
time.Minutes = 0;
time.Seconds = 0;
time.TimeFormat = RTC_HOURFORMAT12_AM;
time.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
time.StoreOperation = RTC_STOREOPERATION_RESET;
if (HAL_RTC_SetTime(&RTCHandle, &time, RTC_FORMAT_BIN) != HAL_OK) {
// init error
return;
}
}
/******************************************************************************/
// MicroPython bindings
typedef struct _pyb_rtc_obj_t {
mp_obj_base_t base;
} pyb_rtc_obj_t;
STATIC const pyb_rtc_obj_t pyb_rtc_obj = {{&pyb_rtc_type}};
/// \classmethod \constructor()
/// Create an RTC object.
STATIC mp_obj_t pyb_rtc_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
// check arguments
mp_arg_check_num(n_args, n_kw, 0, 0, false);
// return constant object
return MP_OBJ_FROM_PTR(&pyb_rtc_obj);
}
// force rtc to re-initialise
mp_obj_t pyb_rtc_init(mp_obj_t self_in) {
rtc_init_start(true);
rtc_init_finalise();
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_1(pyb_rtc_init_obj, pyb_rtc_init);
/// \method info()
/// Get information about the startup time and reset source.
///
/// - The lower 0xffff are the number of milliseconds the RTC took to
/// start up.
/// - Bit 0x10000 is set if a power-on reset occurred.
/// - Bit 0x20000 is set if an external reset occurred
mp_obj_t pyb_rtc_info(mp_obj_t self_in) {
return mp_obj_new_int(rtc_info);
}
MP_DEFINE_CONST_FUN_OBJ_1(pyb_rtc_info_obj, pyb_rtc_info);
/// \method datetime([datetimetuple])
/// Get or set the date and time of the RTC.
///
/// With no arguments, this method returns an 8-tuple with the current
/// date and time. With 1 argument (being an 8-tuple) it sets the date
/// and time.
///
/// The 8-tuple has the following format:
///
/// (year, month, day, weekday, hours, minutes, seconds, subseconds)
///
/// `weekday` is 1-7 for Monday through Sunday.
///
/// `subseconds` counts down from 255 to 0
#define MEG_DIV_64 (1000000 / 64)
#define MEG_DIV_SCALE ((RTC_SYNCH_PREDIV + 1) / 64)
#if defined(MICROPY_HW_RTC_USE_US) && MICROPY_HW_RTC_USE_US
uint32_t rtc_subsec_to_us(uint32_t ss) {
return ((RTC_SYNCH_PREDIV - ss) * MEG_DIV_64) / MEG_DIV_SCALE;
}
uint32_t rtc_us_to_subsec(uint32_t us) {
return RTC_SYNCH_PREDIV - (us * MEG_DIV_SCALE / MEG_DIV_64);
}
#else
#define rtc_us_to_subsec
#define rtc_subsec_to_us
#endif
mp_obj_t pyb_rtc_datetime(size_t n_args, const mp_obj_t *args) {
rtc_init_finalise();
if (n_args == 1) {
// get date and time
// note: need to call get time then get date to correctly access the registers
RTC_DateTypeDef date;
RTC_TimeTypeDef time;
HAL_RTC_GetTime(&RTCHandle, &time, RTC_FORMAT_BIN);
HAL_RTC_GetDate(&RTCHandle, &date, RTC_FORMAT_BIN);
mp_obj_t tuple[8] = {
mp_obj_new_int(2000 + date.Year),
mp_obj_new_int(date.Month),
mp_obj_new_int(date.Date),
mp_obj_new_int(date.WeekDay),
mp_obj_new_int(time.Hours),
mp_obj_new_int(time.Minutes),
mp_obj_new_int(time.Seconds),
mp_obj_new_int(rtc_subsec_to_us(time.SubSeconds)),
};
return mp_obj_new_tuple(8, tuple);
} else {
// set date and time
mp_obj_t *items;
mp_obj_get_array_fixed_n(args[1], 8, &items);
RTC_DateTypeDef date;
date.Year = mp_obj_get_int(items[0]) - 2000;
date.Month = mp_obj_get_int(items[1]);
date.Date = mp_obj_get_int(items[2]);
date.WeekDay = mp_obj_get_int(items[3]);
HAL_RTC_SetDate(&RTCHandle, &date, RTC_FORMAT_BIN);
RTC_TimeTypeDef time;
time.Hours = mp_obj_get_int(items[4]);
time.Minutes = mp_obj_get_int(items[5]);
time.Seconds = mp_obj_get_int(items[6]);
time.TimeFormat = RTC_HOURFORMAT12_AM;
time.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
time.StoreOperation = RTC_STOREOPERATION_SET;
HAL_RTC_SetTime(&RTCHandle, &time, RTC_FORMAT_BIN);
return mp_const_none;
}
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_rtc_datetime_obj, 1, 2, pyb_rtc_datetime);
#if defined(STM32F0) || defined(STM32L0)
#define RTC_WKUP_IRQn RTC_IRQn
#endif
// wakeup(None)
// wakeup(ms, callback=None)
// wakeup(wucksel, wut, callback)
mp_obj_t pyb_rtc_wakeup(size_t n_args, const mp_obj_t *args) {
// wut is wakeup counter start value, wucksel is clock source
// counter is decremented at wucksel rate, and wakes the MCU when it gets to 0
// wucksel=0b000 is RTC/16 (RTC runs at 32768Hz)
// wucksel=0b001 is RTC/8
// wucksel=0b010 is RTC/4
// wucksel=0b011 is RTC/2
// wucksel=0b100 is 1Hz clock
// wucksel=0b110 is 1Hz clock with 0x10000 added to wut
// so a 1 second wakeup could be wut=2047, wucksel=0b000, or wut=4095, wucksel=0b001, etc
rtc_init_finalise();
// disable wakeup IRQ while we configure it
HAL_NVIC_DisableIRQ(RTC_WKUP_IRQn);
bool enable = false;
mp_int_t wucksel;
mp_int_t wut;
mp_obj_t callback = mp_const_none;
if (n_args <= 3) {
if (args[1] == mp_const_none) {
// disable wakeup
} else {
// time given in ms
mp_int_t ms = mp_obj_get_int(args[1]);
mp_int_t div = 2;
wucksel = 3;
while (div <= 16 && ms > 2000 * div) {
div *= 2;
wucksel -= 1;
}
if (div <= 16) {
wut = 32768 / div * ms / 1000;
} else {
// use 1Hz clock
wucksel = 4;
wut = ms / 1000;
if (wut > 0x10000) {
// wut too large for 16-bit register, try to offset by 0x10000
wucksel = 6;
wut -= 0x10000;
if (wut > 0x10000) {
// wut still too large
mp_raise_ValueError(MP_ERROR_TEXT("wakeup value too large"));
}
}
}
// wut register should be 1 less than desired value, but guard against wut=0
if (wut > 0) {
wut -= 1;
}
enable = true;
}
if (n_args == 3) {
callback = args[2];
}
} else {
// config values given directly
wucksel = mp_obj_get_int(args[1]);
wut = mp_obj_get_int(args[2]);
callback = args[3];
enable = true;
}
// set the callback
MP_STATE_PORT(pyb_extint_callback)[EXTI_RTC_WAKEUP] = callback;
// disable register write protection
RTC->WPR = 0xca;
RTC->WPR = 0x53;
// clear WUTE
RTC->CR &= ~RTC_CR_WUTE;
// wait until WUTWF is set
while (!(RTC->ISR & RTC_ISR_WUTWF)) {
}
if (enable) {
// program WUT
RTC->WUTR = wut;
// set WUTIE to enable wakeup interrupts
// set WUTE to enable wakeup
// program WUCKSEL
RTC->CR = (RTC->CR & ~7) | (1 << 14) | (1 << 10) | (wucksel & 7);
// enable register write protection
RTC->WPR = 0xff;
// enable external interrupts on line EXTI_RTC_WAKEUP
#if defined(STM32L4) || defined(STM32WB)
EXTI->IMR1 |= 1 << EXTI_RTC_WAKEUP;
EXTI->RTSR1 |= 1 << EXTI_RTC_WAKEUP;
#elif defined(STM32H7)
EXTI_D1->IMR1 |= 1 << EXTI_RTC_WAKEUP;
EXTI->RTSR1 |= 1 << EXTI_RTC_WAKEUP;
#else
EXTI->IMR |= 1 << EXTI_RTC_WAKEUP;
EXTI->RTSR |= 1 << EXTI_RTC_WAKEUP;
#endif
// clear interrupt flags
RTC->ISR &= ~RTC_ISR_WUTF;
#if defined(STM32L4) || defined(STM32WB)
EXTI->PR1 = 1 << EXTI_RTC_WAKEUP;
#elif defined(STM32H7)
EXTI_D1->PR1 = 1 << EXTI_RTC_WAKEUP;
#else
EXTI->PR = 1 << EXTI_RTC_WAKEUP;
#endif
NVIC_SetPriority(RTC_WKUP_IRQn, IRQ_PRI_RTC_WKUP);
HAL_NVIC_EnableIRQ(RTC_WKUP_IRQn);
//printf("wut=%d wucksel=%d\n", wut, wucksel);
} else {
// clear WUTIE to disable interrupts
RTC->CR &= ~RTC_CR_WUTIE;
// enable register write protection
RTC->WPR = 0xff;
// disable external interrupts on line EXTI_RTC_WAKEUP
#if defined(STM32L4) || defined(STM32WB)
EXTI->IMR1 &= ~(1 << EXTI_RTC_WAKEUP);
#elif defined(STM32H7)
EXTI_D1->IMR1 |= 1 << EXTI_RTC_WAKEUP;
#else
EXTI->IMR &= ~(1 << EXTI_RTC_WAKEUP);
#endif
}
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_rtc_wakeup_obj, 2, 4, pyb_rtc_wakeup);
// calibration(None)
// calibration(cal)
// When an integer argument is provided, check that it falls in the range [-511 to 512]
// and set the calibration value; otherwise return calibration value
mp_obj_t pyb_rtc_calibration(size_t n_args, const mp_obj_t *args) {
rtc_init_finalise();
mp_int_t cal;
if (n_args == 2) {
cal = mp_obj_get_int(args[1]);
mp_uint_t cal_p, cal_m;
if (cal < -511 || cal > 512) {
#if defined(MICROPY_HW_RTC_USE_CALOUT) && MICROPY_HW_RTC_USE_CALOUT
if ((cal & 0xfffe) == 0x0ffe) {
// turn on/off X18 (PC13) 512Hz output
// Note:
// Output will stay active even in VBAT mode (and inrease current)
if (cal & 1) {
HAL_RTCEx_SetCalibrationOutPut(&RTCHandle, RTC_CALIBOUTPUT_512HZ);
} else {
HAL_RTCEx_DeactivateCalibrationOutPut(&RTCHandle);
}
return mp_obj_new_int(cal & 1);
} else {
mp_raise_ValueError(MP_ERROR_TEXT("calibration value out of range"));
}
#else
mp_raise_ValueError(MP_ERROR_TEXT("calibration value out of range"));
#endif
}
if (cal > 0) {
cal_p = RTC_SMOOTHCALIB_PLUSPULSES_SET;
cal_m = 512 - cal;
} else {
cal_p = RTC_SMOOTHCALIB_PLUSPULSES_RESET;
cal_m = -cal;
}
HAL_RTCEx_SetSmoothCalib(&RTCHandle, RTC_SMOOTHCALIB_PERIOD_32SEC, cal_p, cal_m);
return mp_const_none;
} else {
// printf("CALR = 0x%x\n", (mp_uint_t) RTCHandle.Instance->CALR); // DEBUG
// Test if CALP bit is set in CALR:
if (RTCHandle.Instance->CALR & 0x8000) {
cal = 512 - (RTCHandle.Instance->CALR & 0x1ff);
} else {
cal = -(RTCHandle.Instance->CALR & 0x1ff);
}
return mp_obj_new_int(cal);
}
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(pyb_rtc_calibration_obj, 1, 2, pyb_rtc_calibration);
STATIC const mp_rom_map_elem_t pyb_rtc_locals_dict_table[] = {
{ MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&pyb_rtc_init_obj) },
{ MP_ROM_QSTR(MP_QSTR_info), MP_ROM_PTR(&pyb_rtc_info_obj) },
{ MP_ROM_QSTR(MP_QSTR_datetime), MP_ROM_PTR(&pyb_rtc_datetime_obj) },
{ MP_ROM_QSTR(MP_QSTR_wakeup), MP_ROM_PTR(&pyb_rtc_wakeup_obj) },
{ MP_ROM_QSTR(MP_QSTR_calibration), MP_ROM_PTR(&pyb_rtc_calibration_obj) },
};
STATIC MP_DEFINE_CONST_DICT(pyb_rtc_locals_dict, pyb_rtc_locals_dict_table);
const mp_obj_type_t pyb_rtc_type = {
{ &mp_type_type },
.name = MP_QSTR_RTC,
.make_new = pyb_rtc_make_new,
.locals_dict = (mp_obj_dict_t *)&pyb_rtc_locals_dict,
};