mbed library sources modified for open wear
Dependents: openwear-lifelogger-example
Fork of mbed-src by
Diff: targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/stm32f30x_iwdg.c
- Revision:
- 125:23cc3068a9e4
diff -r 73383cc04afd -r 23cc3068a9e4 targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/stm32f30x_iwdg.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/cmsis/TARGET_STM/TARGET_NUCLEO_F302R8/stm32f30x_iwdg.c Wed Mar 19 10:15:22 2014 +0000 @@ -0,0 +1,298 @@ +/** + ****************************************************************************** + * @file stm32f30x_iwdg.c + * @author MCD Application Team + * @version V1.1.0 + * @date 27-February-2014 + * @brief This file provides firmware functions to manage the following + * functionalities of the Independent watchdog (IWDG) peripheral: + * + Prescaler and Counter configuration + * + IWDG activation + * + Flag management + * + @verbatim + + =============================================================================== + ##### IWDG features ##### + =============================================================================== + [..] The IWDG can be started by either software or hardware (configurable + through option byte). + [..] The IWDG is clocked by its own dedicated low-speed clock (LSI) and + thus stays active even if the main clock fails. + Once the IWDG is started, the LSI is forced ON and cannot be disabled + (LSI cannot be disabled too), and the counter starts counting down from + the reset value of 0xFFF. When it reaches the end of count value (0x000) + a system reset is generated. + The IWDG counter should be reloaded at regular intervals to prevent + an MCU reset. + [..] The IWDG is implemented in the VDD voltage domain that is still functional + in STOP and STANDBY mode (IWDG reset can wake-up from STANDBY). + [..] IWDGRST flag in RCC_CSR register can be used to inform when a IWDG + reset occurs. + [..] Min-max timeout value @41KHz (LSI): ~0.1ms / ~25.5s + The IWDG timeout may vary due to LSI frequency dispersion. STM32F30x + devices provide the capability to measure the LSI frequency (LSI clock + connected internally to TIM16 CH1 input capture). The measured value + can be used to have an IWDG timeout with an acceptable accuracy. + For more information, please refer to the STM32F30x Reference manual. + + ##### How to use this driver ##### + =============================================================================== + [..] This driver allows to use IWDG peripheral with either window option enabled + or disabled. To do so follow one of the two procedures below. + (#) Window option is enabled: + (++) Start the IWDG using IWDG_Enable() function, when the IWDG is used + in software mode (no need to enable the LSI, it will be enabled + by hardware). + (++) Enable write access to IWDG_PR and IWDG_RLR registers using + IWDG_WriteAccessCmd(IWDG_WriteAccess_Enable) function. + (++) Configure the IWDG prescaler using IWDG_SetPrescaler() function. + (++) Configure the IWDG counter value using IWDG_SetReload() function. + This value will be loaded in the IWDG counter each time the counter + is reloaded, then the IWDG will start counting down from this value. + (++) Wait for the IWDG registers to be updated using IWDG_GetFlagStatus() function. + (++) Configure the IWDG refresh window using IWDG_SetWindowValue() function. + + (#) Window option is disabled: + (++) Enable write access to IWDG_PR and IWDG_RLR registers using + IWDG_WriteAccessCmd(IWDG_WriteAccess_Enable) function. + (++) Configure the IWDG prescaler using IWDG_SetPrescaler() function. + (++) Configure the IWDG counter value using IWDG_SetReload() function. + This value will be loaded in the IWDG counter each time the counter + is reloaded, then the IWDG will start counting down from this value. + (++) Wait for the IWDG registers to be updated using IWDG_GetFlagStatus() function. + (++) reload the IWDG counter at regular intervals during normal operation + to prevent an MCU reset, using IWDG_ReloadCounter() function. + (++) Start the IWDG using IWDG_Enable() function, when the IWDG is used + in software mode (no need to enable the LSI, it will be enabled + by hardware). + + @endverbatim + + ****************************************************************************** + * @attention + * + * <h2><center>© COPYRIGHT(c) 2014 STMicroelectronics</center></h2> + * + * Redistribution and use in source and binary forms, with or without modification, + * are permitted provided that the following conditions are met: + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * 3. Neither the name of STMicroelectronics nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************** + */ + +/* Includes ------------------------------------------------------------------*/ +#include "stm32f30x_iwdg.h" + +/** @addtogroup STM32F30x_StdPeriph_Driver + * @{ + */ + +/** @defgroup IWDG + * @brief IWDG driver modules + * @{ + */ + +/* Private typedef -----------------------------------------------------------*/ +/* Private define ------------------------------------------------------------*/ +/* ---------------------- IWDG registers bit mask ----------------------------*/ +/* KR register bit mask */ +#define KR_KEY_RELOAD ((uint16_t)0xAAAA) +#define KR_KEY_ENABLE ((uint16_t)0xCCCC) + +/* Private macro -------------------------------------------------------------*/ +/* Private variables ---------------------------------------------------------*/ +/* Private function prototypes -----------------------------------------------*/ +/* Private functions ---------------------------------------------------------*/ + +/** @defgroup IWDG_Private_Functions + * @{ + */ + +/** @defgroup IWDG_Group1 Prescaler and Counter configuration functions + * @brief Prescaler and Counter configuration functions + * +@verbatim + =============================================================================== + ##### Prescaler and Counter configuration functions ##### + =============================================================================== + +@endverbatim + * @{ + */ + +/** + * @brief Enables or disables write access to IWDG_PR and IWDG_RLR registers. + * @param IWDG_WriteAccess: new state of write access to IWDG_PR and IWDG_RLR registers. + * This parameter can be one of the following values: + * @arg IWDG_WriteAccess_Enable: Enable write access to IWDG_PR and IWDG_RLR registers + * @arg IWDG_WriteAccess_Disable: Disable write access to IWDG_PR and IWDG_RLR registers + * @retval None + */ +void IWDG_WriteAccessCmd(uint16_t IWDG_WriteAccess) +{ + /* Check the parameters */ + assert_param(IS_IWDG_WRITE_ACCESS(IWDG_WriteAccess)); + IWDG->KR = IWDG_WriteAccess; +} + +/** + * @brief Sets IWDG Prescaler value. + * @param IWDG_Prescaler: specifies the IWDG Prescaler value. + * This parameter can be one of the following values: + * @arg IWDG_Prescaler_4: IWDG prescaler set to 4 + * @arg IWDG_Prescaler_8: IWDG prescaler set to 8 + * @arg IWDG_Prescaler_16: IWDG prescaler set to 16 + * @arg IWDG_Prescaler_32: IWDG prescaler set to 32 + * @arg IWDG_Prescaler_64: IWDG prescaler set to 64 + * @arg IWDG_Prescaler_128: IWDG prescaler set to 128 + * @arg IWDG_Prescaler_256: IWDG prescaler set to 256 + * @retval None + */ +void IWDG_SetPrescaler(uint8_t IWDG_Prescaler) +{ + /* Check the parameters */ + assert_param(IS_IWDG_PRESCALER(IWDG_Prescaler)); + IWDG->PR = IWDG_Prescaler; +} + +/** + * @brief Sets IWDG Reload value. + * @param Reload: specifies the IWDG Reload value. + * This parameter must be a number between 0 and 0x0FFF. + * @retval None + */ +void IWDG_SetReload(uint16_t Reload) +{ + /* Check the parameters */ + assert_param(IS_IWDG_RELOAD(Reload)); + IWDG->RLR = Reload; +} + +/** + * @brief Reloads IWDG counter with value defined in the reload register + * (write access to IWDG_PR and IWDG_RLR registers disabled). + * @param None + * @retval None + */ +void IWDG_ReloadCounter(void) +{ + IWDG->KR = KR_KEY_RELOAD; +} + + +/** + * @brief Sets the IWDG window value. + * @param WindowValue: specifies the window value to be compared to the downcounter. + * @retval None + */ +void IWDG_SetWindowValue(uint16_t WindowValue) +{ + /* Check the parameters */ + assert_param(IS_IWDG_WINDOW_VALUE(WindowValue)); + IWDG->WINR = WindowValue; +} + +/** + * @} + */ + +/** @defgroup IWDG_Group2 IWDG activation function + * @brief IWDG activation function + * +@verbatim + =============================================================================== + ##### IWDG activation function ##### + =============================================================================== + +@endverbatim + * @{ + */ + +/** + * @brief Enables IWDG (write access to IWDG_PR and IWDG_RLR registers disabled). + * @param None + * @retval None + */ +void IWDG_Enable(void) +{ + IWDG->KR = KR_KEY_ENABLE; +} + +/** + * @} + */ + +/** @defgroup IWDG_Group3 Flag management function + * @brief Flag management function + * +@verbatim + =============================================================================== + ##### Flag management function ##### + =============================================================================== + +@endverbatim + * @{ + */ + +/** + * @brief Checks whether the specified IWDG flag is set or not. + * @param IWDG_FLAG: specifies the flag to check. + * This parameter can be one of the following values: + * @arg IWDG_FLAG_PVU: Prescaler Value Update on going + * @arg IWDG_FLAG_RVU: Reload Value Update on going + * @arg IWDG_FLAG_WVU: Counter Window Value Update on going + * @retval The new state of IWDG_FLAG (SET or RESET). + */ +FlagStatus IWDG_GetFlagStatus(uint16_t IWDG_FLAG) +{ + FlagStatus bitstatus = RESET; + /* Check the parameters */ + assert_param(IS_IWDG_FLAG(IWDG_FLAG)); + if ((IWDG->SR & IWDG_FLAG) != (uint32_t)RESET) + { + bitstatus = SET; + } + else + { + bitstatus = RESET; + } + /* Return the flag status */ + return bitstatus; +} + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ + +/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/