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Diff: targets/cmsis/TARGET_STM/TARGET_DISCO_F051R8/stm32f0xx_rcc.c
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/cmsis/TARGET_STM/TARGET_DISCO_F051R8/stm32f0xx_rcc.c Fri Mar 21 11:45:09 2014 +0000 @@ -0,0 +1,1751 @@ +/** + ****************************************************************************** + * @file stm32f0xx_rcc.c + * @author MCD Application Team + * @version V1.3.0 + * @date 16-January-2014 + * @brief This file provides firmware functions to manage the following + * functionalities of the Reset and clock control (RCC) peripheral: + * + Internal/external clocks, PLL, CSS and MCO configuration + * + System, AHB and APB busses clocks configuration + * + Peripheral clocks configuration + * + Interrupts and flags management + * + @verbatim + + =============================================================================== + ##### RCC specific features ##### + =============================================================================== + [..] After reset the device is running from HSI (8 MHz) with Flash 0 WS, + all peripherals are off except internal SRAM, Flash and SWD. + (#) There is no prescaler on High speed (AHB) and Low speed (APB) busses; + all peripherals mapped on these busses are running at HSI speed. + (#) The clock for all peripherals is switched off, except the SRAM and FLASH. + (#) All GPIOs are in input floating state, except the SWD pins which + are assigned to be used for debug purpose. + [..] Once the device started from reset, the user application has to: + (#) Configure the clock source to be used to drive the System clock + (if the application needs higher frequency/performance) + (#) Configure the System clock frequency and Flash settings + (#) Configure the AHB and APB busses prescalers + (#) Enable the clock for the peripheral(s) to be used + (#) Configure the clock source(s) for peripherals which clocks are not + derived from the System clock (ADC, CEC, I2C, USART, RTC and IWDG) + + @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 "stm32f0xx_rcc.h" + +/** @addtogroup STM32F0xx_StdPeriph_Driver + * @{ + */ + +/** @defgroup RCC + * @brief RCC driver modules + * @{ + */ + +/* Private typedef -----------------------------------------------------------*/ +/* Private define ------------------------------------------------------------*/ + +/* ---------------------- RCC registers mask -------------------------------- */ +/* RCC Flag Mask */ +#define FLAG_MASK ((uint8_t)0x1F) + +/* CR register byte 2 (Bits[23:16]) base address */ +#define CR_BYTE2_ADDRESS ((uint32_t)0x40021002) + +/* CFGR register byte 3 (Bits[31:23]) base address */ +#define CFGR_BYTE3_ADDRESS ((uint32_t)0x40021007) + +/* CIR register byte 1 (Bits[15:8]) base address */ +#define CIR_BYTE1_ADDRESS ((uint32_t)0x40021009) + +/* CIR register byte 2 (Bits[23:16]) base address */ +#define CIR_BYTE2_ADDRESS ((uint32_t)0x4002100A) + +/* Private macro -------------------------------------------------------------*/ +/* Private variables ---------------------------------------------------------*/ +static __I uint8_t APBAHBPrescTable[16] = {0, 0, 0, 0, 1, 2, 3, 4, 1, 2, 3, 4, 6, 7, 8, 9}; + +/* Private function prototypes -----------------------------------------------*/ +/* Private functions ---------------------------------------------------------*/ + +/** @defgroup RCC_Private_Functions + * @{ + */ + +/** @defgroup RCC_Group1 Internal and external clocks, PLL, CSS and MCO configuration functions + * @brief Internal and external clocks, PLL, CSS and MCO configuration functions + * +@verbatim + =============================================================================== + ##### Internal-external clocks, PLL, CSS and MCO configuration functions ##### + =============================================================================== + [..] This section provides functions allowing to configure the internal/external clocks, + PLL, CSS and MCO. + (#) HSI (high-speed internal), 8 MHz factory-trimmed RC used directly + or through the PLL as System clock source. + The HSI clock can be used also to clock the USART, I2C and CEC peripherals. + (#) HSI14 (high-speed internal for ADC), 14 MHz factory-trimmed RC used to clock + the ADC peripheral. + (#) LSI (low-speed internal), 40 KHz low consumption RC used as IWDG and/or RTC + clock source. + (#) HSE (high-speed external), 4 to 32 MHz crystal oscillator used directly or + through the PLL as System clock source. Can be used also as RTC clock source. + (#) LSE (low-speed external), 32 KHz oscillator used as RTC clock source. + LSE can be used also to clock the USART and CEC peripherals. + (#) PLL (clocked by HSI or HSE), for System clock. + (#) CSS (Clock security system), once enabled and if a HSE clock failure occurs + (HSE used directly or through PLL as System clock source), the System clock + is automatically switched to HSI and an interrupt is generated if enabled. + The interrupt is linked to the Cortex-M0 NMI (Non-Maskable Interrupt) + exception vector. + (#) MCO (microcontroller clock output), used to output SYSCLK, HSI, HSI14, LSI, + HSE, LSE or PLL (divided by 2) clock on PA8 pin. + +@endverbatim + * @{ + */ + +/** + * @brief Resets the RCC clock configuration to the default reset state. + * @note The default reset state of the clock configuration is given below: + * @note HSI ON and used as system clock source + * @note HSI14, HSE and PLL OFF + * @note AHB, APB prescaler set to 1. + * @note CSS and MCO OFF + * @note All interrupts disabled + * @note However, this function doesn't modify the configuration of the + * @note Peripheral clocks + * @note LSI, LSE and RTC clocks + * @param None + * @retval None + */ +void RCC_DeInit(void) +{ + /* Set HSION bit */ + RCC->CR |= (uint32_t)0x00000001; + +#if defined (STM32F051) + /* Reset SW[1:0], HPRE[3:0], PPRE[2:0] and MCOSEL[2:0] bits */ + RCC->CFGR &= (uint32_t)0xF8FFB80C; +#else + /* Reset SW[1:0], HPRE[3:0], PPRE[2:0], ADCPRE, MCOSEL[2:0], MCOPRE[2:0] and PLLNODIV bits */ + RCC->CFGR &= (uint32_t)0x08FFB80C; +#endif /* STM32F051 */ + + /* Reset HSEON, CSSON and PLLON bits */ + RCC->CR &= (uint32_t)0xFEF6FFFF; + + /* Reset HSEBYP bit */ + RCC->CR &= (uint32_t)0xFFFBFFFF; + + /* Reset PLLSRC, PLLXTPRE and PLLMUL[3:0] bits */ + RCC->CFGR &= (uint32_t)0xFFC0FFFF; + + /* Reset PREDIV1[3:0] bits */ + RCC->CFGR2 &= (uint32_t)0xFFFFFFF0; + + /* Reset USARTSW[1:0], I2CSW, CECSW and ADCSW bits */ + RCC->CFGR3 &= (uint32_t)0xFFFFFEAC; + + /* Reset HSI14 bit */ + RCC->CR2 &= (uint32_t)0xFFFFFFFE; + + /* Disable all interrupts */ + RCC->CIR = 0x00000000; +} + +/** + * @brief Configures the External High Speed oscillator (HSE). + * @note After enabling the HSE (RCC_HSE_ON or RCC_HSE_Bypass), the application + * software should wait on HSERDY flag to be set indicating that HSE clock + * is stable and can be used to clock the PLL and/or system clock. + * @note HSE state can not be changed if it is used directly or through the + * PLL as system clock. In this case, you have to select another source + * of the system clock then change the HSE state (ex. disable it). + * @note The HSE is stopped by hardware when entering STOP and STANDBY modes. + * @note This function resets the CSSON bit, so if the Clock security system(CSS) + * was previously enabled you have to enable it again after calling this + * function. + * @param RCC_HSE: specifies the new state of the HSE. + * This parameter can be one of the following values: + * @arg RCC_HSE_OFF: turn OFF the HSE oscillator, HSERDY flag goes low after + * 6 HSE oscillator clock cycles. + * @arg RCC_HSE_ON: turn ON the HSE oscillator + * @arg RCC_HSE_Bypass: HSE oscillator bypassed with external clock + * @retval None + */ +void RCC_HSEConfig(uint8_t RCC_HSE) +{ + /* Check the parameters */ + assert_param(IS_RCC_HSE(RCC_HSE)); + + /* Reset HSEON and HSEBYP bits before configuring the HSE ------------------*/ + *(__IO uint8_t *) CR_BYTE2_ADDRESS = RCC_HSE_OFF; + + /* Set the new HSE configuration -------------------------------------------*/ + *(__IO uint8_t *) CR_BYTE2_ADDRESS = RCC_HSE; + +} + +/** + * @brief Waits for HSE start-up. + * @note This function waits on HSERDY flag to be set and return SUCCESS if + * this flag is set, otherwise returns ERROR if the timeout is reached + * and this flag is not set. The timeout value is defined by the constant + * HSE_STARTUP_TIMEOUT in stm32f0xx.h file. You can tailor it depending + * on the HSE crystal used in your application. + * @note The HSE is stopped by hardware when entering STOP and STANDBY modes. + * @param None + * @retval An ErrorStatus enumeration value: + * - SUCCESS: HSE oscillator is stable and ready to use + * - ERROR: HSE oscillator not yet ready + */ +ErrorStatus RCC_WaitForHSEStartUp(void) +{ + __IO uint32_t StartUpCounter = 0; + ErrorStatus status = ERROR; + FlagStatus HSEStatus = RESET; + + /* Wait till HSE is ready and if timeout is reached exit */ + do + { + HSEStatus = RCC_GetFlagStatus(RCC_FLAG_HSERDY); + StartUpCounter++; + } while((StartUpCounter != HSE_STARTUP_TIMEOUT) && (HSEStatus == RESET)); + + if (RCC_GetFlagStatus(RCC_FLAG_HSERDY) != RESET) + { + status = SUCCESS; + } + else + { + status = ERROR; + } + return (status); +} + +/** + * @brief Adjusts the Internal High Speed oscillator (HSI) calibration value. + * @note The calibration is used to compensate for the variations in voltage + * and temperature that influence the frequency of the internal HSI RC. + * Refer to the Application Note AN4067 for more details on how to + * calibrate the HSI. + * @param HSICalibrationValue: specifies the HSI calibration trimming value. + * This parameter must be a number between 0 and 0x1F. + * @retval None + */ +void RCC_AdjustHSICalibrationValue(uint8_t HSICalibrationValue) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_HSI_CALIBRATION_VALUE(HSICalibrationValue)); + + tmpreg = RCC->CR; + + /* Clear HSITRIM[4:0] bits */ + tmpreg &= ~RCC_CR_HSITRIM; + + /* Set the HSITRIM[4:0] bits according to HSICalibrationValue value */ + tmpreg |= (uint32_t)HSICalibrationValue << 3; + + /* Store the new value */ + RCC->CR = tmpreg; +} + +/** + * @brief Enables or disables the Internal High Speed oscillator (HSI). + * @note After enabling the HSI, the application software should wait on + * HSIRDY flag to be set indicating that HSI clock is stable and can + * be used to clock the PLL and/or system clock. + * @note HSI can not be stopped if it is used directly or through the PLL + * as system clock. In this case, you have to select another source + * of the system clock then stop the HSI. + * @note The HSI is stopped by hardware when entering STOP and STANDBY modes. + * @param NewState: new state of the HSI. + * This parameter can be: ENABLE or DISABLE. + * @note When the HSI is stopped, HSIRDY flag goes low after 6 HSI oscillator + * clock cycles. + * @retval None + */ +void RCC_HSICmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR |= RCC_CR_HSION; + } + else + { + RCC->CR &= ~RCC_CR_HSION; + } +} + +/** + * @brief Adjusts the Internal High Speed oscillator for ADC (HSI14) + * calibration value. + * @note The calibration is used to compensate for the variations in voltage + * and temperature that influence the frequency of the internal HSI RC. + * Refer to the Application Note AN4067 for more details on how to + * calibrate the HSI14. + * @param HSI14CalibrationValue: specifies the HSI14 calibration trimming value. + * This parameter must be a number between 0 and 0x1F. + * @retval None + */ +void RCC_AdjustHSI14CalibrationValue(uint8_t HSI14CalibrationValue) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_HSI14_CALIBRATION_VALUE(HSI14CalibrationValue)); + + tmpreg = RCC->CR2; + + /* Clear HSI14TRIM[4:0] bits */ + tmpreg &= ~RCC_CR2_HSI14TRIM; + + /* Set the HSITRIM14[4:0] bits according to HSI14CalibrationValue value */ + tmpreg |= (uint32_t)HSI14CalibrationValue << 3; + + /* Store the new value */ + RCC->CR2 = tmpreg; +} + +/** + * @brief Enables or disables the Internal High Speed oscillator for ADC (HSI14). + * @note After enabling the HSI14, the application software should wait on + * HSIRDY flag to be set indicating that HSI clock is stable and can + * be used to clock the ADC. + * @note The HSI14 is stopped by hardware when entering STOP and STANDBY modes. + * @param NewState: new state of the HSI14. + * This parameter can be: ENABLE or DISABLE. + * @note When the HSI14 is stopped, HSI14RDY flag goes low after 6 HSI14 oscillator + * clock cycles. + * @retval None + */ +void RCC_HSI14Cmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR2 |= RCC_CR2_HSI14ON; + } + else + { + RCC->CR2 &= ~RCC_CR2_HSI14ON; + } +} + +/** + * @brief Enables or disables the Internal High Speed oscillator request from ADC. + * @param NewState: new state of the HSI14 ADC request. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_HSI14ADCRequestCmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR2 &= ~RCC_CR2_HSI14DIS; + } + else + { + RCC->CR2 |= RCC_CR2_HSI14DIS; + } +} + +/** + * @brief Configures the External Low Speed oscillator (LSE). + * @note As the LSE is in the Backup domain and write access is denied to this + * domain after reset, you have to enable write access using + * PWR_BackupAccessCmd(ENABLE) function before to configure the LSE + * (to be done once after reset). + * @note After enabling the LSE (RCC_LSE_ON or RCC_LSE_Bypass), the application + * software should wait on LSERDY flag to be set indicating that LSE clock + * is stable and can be used to clock the RTC. + * @param RCC_LSE: specifies the new state of the LSE. + * This parameter can be one of the following values: + * @arg RCC_LSE_OFF: turn OFF the LSE oscillator, LSERDY flag goes low after + * 6 LSE oscillator clock cycles. + * @arg RCC_LSE_ON: turn ON the LSE oscillator + * @arg RCC_LSE_Bypass: LSE oscillator bypassed with external clock + * @retval None + */ +void RCC_LSEConfig(uint32_t RCC_LSE) +{ + /* Check the parameters */ + assert_param(IS_RCC_LSE(RCC_LSE)); + + /* Reset LSEON and LSEBYP bits before configuring the LSE ------------------*/ + /* Reset LSEON bit */ + RCC->BDCR &= ~(RCC_BDCR_LSEON); + + /* Reset LSEBYP bit */ + RCC->BDCR &= ~(RCC_BDCR_LSEBYP); + + /* Configure LSE */ + RCC->BDCR |= RCC_LSE; +} + +/** + * @brief Configures the External Low Speed oscillator (LSE) drive capability. + * @param RCC_LSEDrive: specifies the new state of the LSE drive capability. + * This parameter can be one of the following values: + * @arg RCC_LSEDrive_Low: LSE oscillator low drive capability. + * @arg RCC_LSEDrive_MediumLow: LSE oscillator medium low drive capability. + * @arg RCC_LSEDrive_MediumHigh: LSE oscillator medium high drive capability. + * @arg RCC_LSEDrive_High: LSE oscillator high drive capability. + * @retval None + */ +void RCC_LSEDriveConfig(uint32_t RCC_LSEDrive) +{ + /* Check the parameters */ + assert_param(IS_RCC_LSE_DRIVE(RCC_LSEDrive)); + + /* Clear LSEDRV[1:0] bits */ + RCC->BDCR &= ~(RCC_BDCR_LSEDRV); + + /* Set the LSE Drive */ + RCC->BDCR |= RCC_LSEDrive; +} + +/** + * @brief Enables or disables the Internal Low Speed oscillator (LSI). + * @note After enabling the LSI, the application software should wait on + * LSIRDY flag to be set indicating that LSI clock is stable and can + * be used to clock the IWDG and/or the RTC. + * @note LSI can not be disabled if the IWDG is running. + * @param NewState: new state of the LSI. + * This parameter can be: ENABLE or DISABLE. + * @note When the LSI is stopped, LSIRDY flag goes low after 6 LSI oscillator + * clock cycles. + * @retval None + */ +void RCC_LSICmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CSR |= RCC_CSR_LSION; + } + else + { + RCC->CSR &= ~RCC_CSR_LSION; + } +} + +/** + * @brief Configures the PLL clock source and multiplication factor. + * @note This function must be used only when the PLL is disabled. + * + * @param RCC_PLLSource: specifies the PLL entry clock source. + * This parameter can be one of the following values: + * @arg RCC_PLLSource_HSI_Div2: HSI oscillator clock selected as PLL clock source + * @arg RCC_PLLSource_PREDIV1: PREDIV1 clock selected as PLL clock entry + * @arg RCC_PLLSource_HSI48 HSI48 oscillator clock selected as PLL clock source, applicable only for STM32F072 devices + * @arg RCC_PLLSource_HSI: HSI clock selected as PLL clock entry, applicable only for STM32F072 devices + * @note The minimum input clock frequency for PLL is 2 MHz (when using HSE as + * PLL source). + * + * @param RCC_PLLMul: specifies the PLL multiplication factor, which drive the PLLVCO clock + * This parameter can be RCC_PLLMul_x where x:[2,16] + * + * @retval None + */ +void RCC_PLLConfig(uint32_t RCC_PLLSource, uint32_t RCC_PLLMul) +{ + /* Check the parameters */ + assert_param(IS_RCC_PLL_SOURCE(RCC_PLLSource)); + assert_param(IS_RCC_PLL_MUL(RCC_PLLMul)); + + /* Clear PLL Source [16] and Multiplier [21:18] bits */ + RCC->CFGR &= ~(RCC_CFGR_PLLMULL | RCC_CFGR_PLLSRC); + + /* Set the PLL Source and Multiplier */ + RCC->CFGR |= (uint32_t)(RCC_PLLSource | RCC_PLLMul); +} + +/** + * @brief Enables or disables the PLL. + * @note After enabling the PLL, the application software should wait on + * PLLRDY flag to be set indicating that PLL clock is stable and can + * be used as system clock source. + * @note The PLL can not be disabled if it is used as system clock source + * @note The PLL is disabled by hardware when entering STOP and STANDBY modes. + * @param NewState: new state of the PLL. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_PLLCmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR |= RCC_CR_PLLON; + } + else + { + RCC->CR &= ~RCC_CR_PLLON; + } +} + +/** + * @brief Enables or disables the Internal High Speed oscillator for USB (HSI48). + * This function is only applicable for STM32F072 devices. + * @note After enabling the HSI48, the application software should wait on + * HSI48RDY flag to be set indicating that HSI48 clock is stable and can + * be used to clock the USB. + * @note The HSI48 is stopped by hardware when entering STOP and STANDBY modes. + * @param NewState: new state of the HSI48. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_HSI48Cmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR2 |= RCC_CR2_HSI48ON; + } + else + { + RCC->CR2 &= ~RCC_CR2_HSI48ON; + } +} + +/** + * @brief Configures the PREDIV1 division factor. + * @note This function must be used only when the PLL is disabled. + * @param RCC_PREDIV1_Div: specifies the PREDIV1 clock division factor. + * This parameter can be RCC_PREDIV1_Divx where x:[1,16] + * @retval None + */ +void RCC_PREDIV1Config(uint32_t RCC_PREDIV1_Div) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_PREDIV1(RCC_PREDIV1_Div)); + + tmpreg = RCC->CFGR2; + /* Clear PREDIV1[3:0] bits */ + tmpreg &= ~(RCC_CFGR2_PREDIV1); + /* Set the PREDIV1 division factor */ + tmpreg |= RCC_PREDIV1_Div; + /* Store the new value */ + RCC->CFGR2 = tmpreg; +} + +/** + * @brief Enables or disables the Clock Security System. + * @note If a failure is detected on the HSE oscillator clock, this oscillator + * is automatically disabled and an interrupt is generated to inform the + * software about the failure (Clock Security System Interrupt, CSSI), + * allowing the MCU to perform rescue operations. The CSSI is linked to + * the Cortex-M0 NMI (Non-Maskable Interrupt) exception vector. + * @param NewState: new state of the Clock Security System. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_ClockSecuritySystemCmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->CR |= RCC_CR_CSSON; + } + else + { + RCC->CR &= ~RCC_CR_CSSON; + } +} + +#ifdef STM32F051 +/** + * @brief Selects the clock source to output on MCO pin (PA8). + * @note PA8 should be configured in alternate function mode. + * @param RCC_MCOSource: specifies the clock source to output. + * This parameter can be one of the following values: + * @arg RCC_MCOSource_NoClock: No clock selected. + * @arg RCC_MCOSource_HSI14: HSI14 oscillator clock selected. + * @arg RCC_MCOSource_LSI: LSI oscillator clock selected. + * @arg RCC_MCOSource_LSE: LSE oscillator clock selected. + * @arg RCC_MCOSource_SYSCLK: System clock selected. + * @arg RCC_MCOSource_HSI: HSI oscillator clock selected. + * @arg RCC_MCOSource_HSE: HSE oscillator clock selected. + * @arg RCC_MCOSource_PLLCLK_Div2: PLL clock divided by 2 selected. + * @retval None + */ +void RCC_MCOConfig(uint8_t RCC_MCOSource) +{ + /* Check the parameters */ + assert_param(IS_RCC_MCO_SOURCE(RCC_MCOSource)); + + /* Select MCO clock source and prescaler */ + *(__IO uint8_t *) CFGR_BYTE3_ADDRESS = RCC_MCOSource; +} +#else + +/** + * @brief Selects the clock source to output on MCO pin (PA8) and the corresponding + * prescsaler. + * @note PA8 should be configured in alternate function mode. + * @param RCC_MCOSource: specifies the clock source to output. + * This parameter can be one of the following values: + * @arg RCC_MCOSource_NoClock: No clock selected. + * @arg RCC_MCOSource_HSI14: HSI14 oscillator clock selected. + * @arg RCC_MCOSource_LSI: LSI oscillator clock selected. + * @arg RCC_MCOSource_LSE: LSE oscillator clock selected. + * @arg RCC_MCOSource_SYSCLK: System clock selected. + * @arg RCC_MCOSource_HSI: HSI oscillator clock selected. + * @arg RCC_MCOSource_HSE: HSE oscillator clock selected. + * @arg RCC_MCOSource_PLLCLK_Div2: PLL clock divided by 2 selected. + * @arg RCC_MCOSource_PLLCLK: PLL clock selected. + * @arg RCC_MCOSource_HSI48: HSI48 clock selected. + * @param RCC_MCOPrescaler: specifies the prescaler on MCO pin. + * This parameter can be one of the following values: + * @arg RCC_MCOPrescaler_1: MCO clock is divided by 1. + * @arg RCC_MCOPrescaler_2: MCO clock is divided by 2. + * @arg RCC_MCOPrescaler_4: MCO clock is divided by 4. + * @arg RCC_MCOPrescaler_8: MCO clock is divided by 8. + * @arg RCC_MCOPrescaler_16: MCO clock is divided by 16. + * @arg RCC_MCOPrescaler_32: MCO clock is divided by 32. + * @arg RCC_MCOPrescaler_64: MCO clock is divided by 64. + * @arg RCC_MCOPrescaler_128: MCO clock is divided by 128. + * @retval None + */ +void RCC_MCOConfig(uint8_t RCC_MCOSource, uint32_t RCC_MCOPrescaler) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_MCO_SOURCE(RCC_MCOSource)); + assert_param(IS_RCC_MCO_PRESCALER(RCC_MCOPrescaler)); + + /* Get CFGR value */ + tmpreg = RCC->CFGR; + /* Clear MCOPRE[2:0] bits */ + tmpreg &= ~(RCC_CFGR_MCO_PRE | RCC_CFGR_MCO | RCC_CFGR_PLLNODIV); + /* Set the RCC_MCOSource and RCC_MCOPrescaler */ + tmpreg |= (RCC_MCOPrescaler | ((uint32_t)RCC_MCOSource<<24)); + /* Store the new value */ + RCC->CFGR = tmpreg; +} +#endif /* STM32F072 */ + +/** + * @} + */ + +/** @defgroup RCC_Group2 System AHB and APB busses clocks configuration functions + * @brief System, AHB and APB busses clocks configuration functions + * +@verbatim + =============================================================================== + ##### System, AHB and APB busses clocks configuration functions ##### + =============================================================================== + + [..] This section provide functions allowing to configure the System, AHB and + APB busses clocks. + (#) Several clock sources can be used to drive the System clock (SYSCLK): HSI, + HSE and PLL. + The AHB clock (HCLK) is derived from System clock through configurable prescaler + and used to clock the CPU, memory and peripherals mapped on AHB bus (DMA and GPIO). + and APB (PCLK) clocks are derived from AHB clock through + configurable prescalers and used to clock the peripherals mapped on these busses. + You can use "RCC_GetClocksFreq()" function to retrieve the frequencies of these clocks. + + -@- All the peripheral clocks are derived from the System clock (SYSCLK) except: + (+@) The ADC clock which is derived from HSI14 or APB (APB divided by a + programmable prescaler: 2 or 4). + (+@) The CEC clock which is derived from LSE or HSI divided by 244. + (+@) The I2C clock which is derived from HSI or system clock (SYSCLK). + (+@) The USART clock which is derived from HSI, system clock (SYSCLK), APB or LSE. + (+@) The RTC/LCD clock which is derived from the LSE, LSI or 2 MHz HSE_RTC (HSE + divided by a programmable prescaler). + The System clock (SYSCLK) frequency must be higher or equal to the RTC/LCD + clock frequency. + (+@) IWDG clock which is always the LSI clock. + + (#) The maximum frequency of the SYSCLK, HCLK and PCLK is 48 MHz. + Depending on the maximum frequency, the FLASH wait states (WS) should be + adapted accordingly: + +--------------------------------------------- + + | Wait states | HCLK clock frequency (MHz) | + |---------------|------------------------------| + |0WS(1CPU cycle)| 0 < HCLK <= 24 | + |---------------|------------------------------| + |1WS(2CPU cycle)| 24 < HCLK <= 48 | + +----------------------------------------------+ + + (#) After reset, the System clock source is the HSI (8 MHz) with 0 WS and + prefetch is disabled. + + [..] It is recommended to use the following software sequences to tune the number + of wait states needed to access the Flash memory with the CPU frequency (HCLK). + (+) Increasing the CPU frequency + (++) Program the Flash Prefetch buffer, using "FLASH_PrefetchBufferCmd(ENABLE)" + function + (++) Check that Flash Prefetch buffer activation is taken into account by + reading FLASH_ACR using the FLASH_GetPrefetchBufferStatus() function + (++) Program Flash WS to 1, using "FLASH_SetLatency(FLASH_Latency_1)" function + (++) Check that the new number of WS is taken into account by reading FLASH_ACR + (++) Modify the CPU clock source, using "RCC_SYSCLKConfig()" function + (++) If needed, modify the CPU clock prescaler by using "RCC_HCLKConfig()" function + (++) Check that the new CPU clock source is taken into account by reading + the clock source status, using "RCC_GetSYSCLKSource()" function + (+) Decreasing the CPU frequency + (++) Modify the CPU clock source, using "RCC_SYSCLKConfig()" function + (++) If needed, modify the CPU clock prescaler by using "RCC_HCLKConfig()" function + (++) Check that the new CPU clock source is taken into account by reading + the clock source status, using "RCC_GetSYSCLKSource()" function + (++) Program the new number of WS, using "FLASH_SetLatency()" function + (++) Check that the new number of WS is taken into account by reading FLASH_ACR + (++) Disable the Flash Prefetch buffer using "FLASH_PrefetchBufferCmd(DISABLE)" + function + (++) Check that Flash Prefetch buffer deactivation is taken into account by reading FLASH_ACR + using the FLASH_GetPrefetchBufferStatus() function. + +@endverbatim + * @{ + */ + +/** + * @brief Configures the system clock (SYSCLK). + * @note The HSI is used (enabled by hardware) as system clock source after + * startup from Reset, wake-up from STOP and STANDBY mode, or in case + * of failure of the HSE used directly or indirectly as system clock + * (if the Clock Security System CSS is enabled). + * @note A switch from one clock source to another occurs only if the target + * clock source is ready (clock stable after startup delay or PLL locked). + * If a clock source which is not yet ready is selected, the switch will + * occur when the clock source will be ready. + * You can use RCC_GetSYSCLKSource() function to know which clock is + * currently used as system clock source. + * @param RCC_SYSCLKSource: specifies the clock source used as system clock source + * This parameter can be one of the following values: + * @arg RCC_SYSCLKSource_HSI: HSI selected as system clock source + * @arg RCC_SYSCLKSource_HSE: HSE selected as system clock source + * @arg RCC_SYSCLKSource_PLLCLK: PLL selected as system clock source + * @arg RCC_SYSCLKSource_HSI48: HSI48 selected as system clock source, applicable only for STM32F072 devices + * @retval None + */ +void RCC_SYSCLKConfig(uint32_t RCC_SYSCLKSource) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_SYSCLK_SOURCE(RCC_SYSCLKSource)); + + tmpreg = RCC->CFGR; + + /* Clear SW[1:0] bits */ + tmpreg &= ~RCC_CFGR_SW; + + /* Set SW[1:0] bits according to RCC_SYSCLKSource value */ + tmpreg |= RCC_SYSCLKSource; + + /* Store the new value */ + RCC->CFGR = tmpreg; +} + +/** + * @brief Returns the clock source used as system clock. + * @param None + * @retval The clock source used as system clock. The returned value can be one + * of the following values: + * - 0x00: HSI used as system clock + * - 0x04: HSE used as system clock + * - 0x08: PLL used as system clock + * - 0x0C: HSI48 used as system clock, applicable only for STM32F072 devices + */ +uint8_t RCC_GetSYSCLKSource(void) +{ + return ((uint8_t)(RCC->CFGR & RCC_CFGR_SWS)); +} + +/** + * @brief Configures the AHB clock (HCLK). + * @param RCC_SYSCLK: defines the AHB clock divider. This clock is derived from + * the system clock (SYSCLK). + * This parameter can be one of the following values: + * @arg RCC_SYSCLK_Div1: AHB clock = SYSCLK + * @arg RCC_SYSCLK_Div2: AHB clock = SYSCLK/2 + * @arg RCC_SYSCLK_Div4: AHB clock = SYSCLK/4 + * @arg RCC_SYSCLK_Div8: AHB clock = SYSCLK/8 + * @arg RCC_SYSCLK_Div16: AHB clock = SYSCLK/16 + * @arg RCC_SYSCLK_Div64: AHB clock = SYSCLK/64 + * @arg RCC_SYSCLK_Div128: AHB clock = SYSCLK/128 + * @arg RCC_SYSCLK_Div256: AHB clock = SYSCLK/256 + * @arg RCC_SYSCLK_Div512: AHB clock = SYSCLK/512 + * @retval None + */ +void RCC_HCLKConfig(uint32_t RCC_SYSCLK) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_HCLK(RCC_SYSCLK)); + + tmpreg = RCC->CFGR; + + /* Clear HPRE[3:0] bits */ + tmpreg &= ~RCC_CFGR_HPRE; + + /* Set HPRE[3:0] bits according to RCC_SYSCLK value */ + tmpreg |= RCC_SYSCLK; + + /* Store the new value */ + RCC->CFGR = tmpreg; +} + +/** + * @brief Configures the APB clock (PCLK). + * @param RCC_HCLK: defines the APB clock divider. This clock is derived from + * the AHB clock (HCLK). + * This parameter can be one of the following values: + * @arg RCC_HCLK_Div1: APB clock = HCLK + * @arg RCC_HCLK_Div2: APB clock = HCLK/2 + * @arg RCC_HCLK_Div4: APB clock = HCLK/4 + * @arg RCC_HCLK_Div8: APB clock = HCLK/8 + * @arg RCC_HCLK_Div16: APB clock = HCLK/16 + * @retval None + */ +void RCC_PCLKConfig(uint32_t RCC_HCLK) +{ + uint32_t tmpreg = 0; + + /* Check the parameters */ + assert_param(IS_RCC_PCLK(RCC_HCLK)); + + tmpreg = RCC->CFGR; + + /* Clear PPRE[2:0] bits */ + tmpreg &= ~RCC_CFGR_PPRE; + + /* Set PPRE[2:0] bits according to RCC_HCLK value */ + tmpreg |= RCC_HCLK; + + /* Store the new value */ + RCC->CFGR = tmpreg; +} + +/** + * @brief Configures the ADC clock (ADCCLK). + * @note This function is obsolete. + * For proper ADC clock selection, refer to ADC_ClockModeConfig() in the ADC driver + * @param RCC_ADCCLK: defines the ADC clock source. This clock is derived + * from the HSI14 or APB clock (PCLK). + * This parameter can be one of the following values: + * @arg RCC_ADCCLK_HSI14: ADC clock = HSI14 (14MHz) + * @arg RCC_ADCCLK_PCLK_Div2: ADC clock = PCLK/2 + * @arg RCC_ADCCLK_PCLK_Div4: ADC clock = PCLK/4 + * @retval None + */ +void RCC_ADCCLKConfig(uint32_t RCC_ADCCLK) +{ + /* Check the parameters */ + assert_param(IS_RCC_ADCCLK(RCC_ADCCLK)); + + /* Clear ADCPRE bit */ + RCC->CFGR &= ~RCC_CFGR_ADCPRE; + /* Set ADCPRE bits according to RCC_PCLK value */ + RCC->CFGR |= RCC_ADCCLK & 0xFFFF; + + /* Clear ADCSW bit */ + RCC->CFGR3 &= ~RCC_CFGR3_ADCSW; + /* Set ADCSW bits according to RCC_ADCCLK value */ + RCC->CFGR3 |= RCC_ADCCLK >> 16; +} + +/** + * @brief Configures the CEC clock (CECCLK). + * @param RCC_CECCLK: defines the CEC clock source. This clock is derived + * from the HSI or LSE clock. + * This parameter can be one of the following values: + * @arg RCC_CECCLK_HSI_Div244: CEC clock = HSI/244 (32768Hz) + * @arg RCC_CECCLK_LSE: CEC clock = LSE + * @retval None + */ +void RCC_CECCLKConfig(uint32_t RCC_CECCLK) +{ + /* Check the parameters */ + assert_param(IS_RCC_CECCLK(RCC_CECCLK)); + + /* Clear CECSW bit */ + RCC->CFGR3 &= ~RCC_CFGR3_CECSW; + /* Set CECSW bits according to RCC_CECCLK value */ + RCC->CFGR3 |= RCC_CECCLK; +} + +/** + * @brief Configures the I2C1 clock (I2C1CLK). + * @param RCC_I2CCLK: defines the I2C1 clock source. This clock is derived + * from the HSI or System clock. + * This parameter can be one of the following values: + * @arg RCC_I2C1CLK_HSI: I2C1 clock = HSI + * @arg RCC_I2C1CLK_SYSCLK: I2C1 clock = System Clock + * @retval None + */ +void RCC_I2CCLKConfig(uint32_t RCC_I2CCLK) +{ + /* Check the parameters */ + assert_param(IS_RCC_I2CCLK(RCC_I2CCLK)); + + /* Clear I2CSW bit */ + RCC->CFGR3 &= ~RCC_CFGR3_I2C1SW; + /* Set I2CSW bits according to RCC_I2CCLK value */ + RCC->CFGR3 |= RCC_I2CCLK; +} + +/** + * @brief Configures the USART1 clock (USART1CLK). + * @param RCC_USARTCLK: defines the USART clock source. This clock is derived + * from the HSI or System clock. + * This parameter can be one of the following values: + * @arg RCC_USART1CLK_PCLK: USART1 clock = APB Clock (PCLK) + * @arg RCC_USART1CLK_SYSCLK: USART1 clock = System Clock + * @arg RCC_USART1CLK_LSE: USART1 clock = LSE Clock + * @arg RCC_USART1CLK_HSI: USART1 clock = HSI Clock + * @arg RCC_USART2CLK_PCLK: USART2 clock = APB Clock (PCLK), applicable only for STM32F072 devices + * @arg RCC_USART2CLK_SYSCLK: USART2 clock = System Clock, applicable only for STM32F072 devices + * @arg RCC_USART2CLK_LSE: USART2 clock = LSE Clock, applicable only for STM32F072 devices + * @arg RCC_USART2CLK_HSI: USART2 clock = HSI Clock, applicable only for STM32F072 devices + * @retval None + */ +void RCC_USARTCLKConfig(uint32_t RCC_USARTCLK) +{ + uint32_t tmp = 0; + + /* Check the parameters */ + assert_param(IS_RCC_USARTCLK(RCC_USARTCLK)); + + /* Get USART index */ + tmp = (RCC_USARTCLK >> 28); + + /* Clear USARTSW[1:0] bit */ + if (tmp == (uint32_t)0x00000001) + { + /* Clear USART1SW[1:0] bit */ + RCC->CFGR3 &= ~RCC_CFGR3_USART1SW; + } + else + { + /* Clear USART2SW[1:0] bit */ + RCC->CFGR3 &= ~RCC_CFGR3_USART2SW; + } + + /* Set USARTxSW bits according to RCC_USARTCLK value */ + RCC->CFGR3 |= RCC_USARTCLK; +} + +/** + * @brief Configures the USB clock (USBCLK). + * This function is only applicable for STM32F072 devices. + * @param RCC_USBCLK: defines the USB clock source. This clock is derived + * from the HSI48 or system clock. + * This parameter can be one of the following values: + * @arg RCC_USBCLK_HSI48: USB clock = HSI48 + * @arg RCC_USBCLK_PLLCLK: USB clock = PLL clock + * @retval None + */ +void RCC_USBCLKConfig(uint32_t RCC_USBCLK) +{ + /* Check the parameters */ + assert_param(IS_RCC_USBCLK(RCC_USBCLK)); + + /* Clear USBSW bit */ + RCC->CFGR3 &= ~RCC_CFGR3_USBSW; + /* Set USBSW bits according to RCC_USBCLK value */ + RCC->CFGR3 |= RCC_USBCLK; +} + +/** + * @brief Returns the frequencies of the System, AHB and APB busses clocks. + * @note The frequency returned by this function is not the real frequency + * in the chip. It is calculated based on the predefined constant and + * the source selected by RCC_SYSCLKConfig(): + * + * @note If SYSCLK source is HSI, function returns constant HSI_VALUE(*) + * + * @note If SYSCLK source is HSE, function returns constant HSE_VALUE(**) + * + * @note If SYSCLK source is PLL, function returns constant HSE_VALUE(**) + * or HSI_VALUE(*) multiplied by the PLL factors. + * + * @note If SYSCLK source is HSI48, function returns constant HSI48_VALUE(***) + * + * @note (*) HSI_VALUE is a constant defined in stm32f0xx.h file (default value + * 8 MHz) but the real value may vary depending on the variations + * in voltage and temperature, refer to RCC_AdjustHSICalibrationValue(). + * + * @note (**) HSE_VALUE is a constant defined in stm32f0xx.h file (default value + * 8 MHz), user has to ensure that HSE_VALUE is same as the real + * frequency of the crystal used. Otherwise, this function may + * return wrong result. + * + * @note (***) HSI48_VALUE is a constant defined in stm32f0xx.h file (default value + * 48 MHz) but the real value may vary depending on the variations + * in voltage and temperature. + * + * @note The result of this function could be not correct when using fractional + * value for HSE crystal. + * + * @param RCC_Clocks: pointer to a RCC_ClocksTypeDef structure which will hold + * the clocks frequencies. + * + * @note This function can be used by the user application to compute the + * baudrate for the communication peripherals or configure other parameters. + * @note Each time SYSCLK, HCLK and/or PCLK clock changes, this function + * must be called to update the structure's field. Otherwise, any + * configuration based on this function will be incorrect. + * + * @retval None + */ +void RCC_GetClocksFreq(RCC_ClocksTypeDef* RCC_Clocks) +{ + uint32_t tmp = 0, pllmull = 0, pllsource = 0, prediv1factor = 0, presc = 0, pllclk = 0; + + /* Get SYSCLK source -------------------------------------------------------*/ + tmp = RCC->CFGR & RCC_CFGR_SWS; + + switch (tmp) + { + case 0x00: /* HSI used as system clock */ + RCC_Clocks->SYSCLK_Frequency = HSI_VALUE; + break; + case 0x04: /* HSE used as system clock */ + RCC_Clocks->SYSCLK_Frequency = HSE_VALUE; + break; + case 0x08: /* PLL used as system clock */ + /* Get PLL clock source and multiplication factor ----------------------*/ + pllmull = RCC->CFGR & RCC_CFGR_PLLMULL; + pllsource = RCC->CFGR & RCC_CFGR_PLLSRC; + pllmull = ( pllmull >> 18) + 2; + + if (pllsource == 0x00) + { + /* HSI oscillator clock divided by 2 selected as PLL clock entry */ + pllclk = (HSI_VALUE >> 1) * pllmull; + } + else + { + prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1; + /* HSE oscillator clock selected as PREDIV1 clock entry */ + pllclk = (HSE_VALUE / prediv1factor) * pllmull; + } + RCC_Clocks->SYSCLK_Frequency = pllclk; + break; + case 0x0C: /* HSI48 used as system clock */ + RCC_Clocks->SYSCLK_Frequency = HSI48_VALUE; + break; + default: /* HSI used as system clock */ + RCC_Clocks->SYSCLK_Frequency = HSI_VALUE; + break; + } + /* Compute HCLK, PCLK clocks frequencies -----------------------------------*/ + /* Get HCLK prescaler */ + tmp = RCC->CFGR & RCC_CFGR_HPRE; + tmp = tmp >> 4; + presc = APBAHBPrescTable[tmp]; + /* HCLK clock frequency */ + RCC_Clocks->HCLK_Frequency = RCC_Clocks->SYSCLK_Frequency >> presc; + + /* Get PCLK prescaler */ + tmp = RCC->CFGR & RCC_CFGR_PPRE; + tmp = tmp >> 8; + presc = APBAHBPrescTable[tmp]; + /* PCLK clock frequency */ + RCC_Clocks->PCLK_Frequency = RCC_Clocks->HCLK_Frequency >> presc; + + /* ADCCLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_ADCSW) != RCC_CFGR3_ADCSW) + { + /* ADC Clock is HSI14 Osc. */ + RCC_Clocks->ADCCLK_Frequency = HSI14_VALUE; + } + else + { + if((RCC->CFGR & RCC_CFGR_ADCPRE) != RCC_CFGR_ADCPRE) + { + /* ADC Clock is derived from PCLK/2 */ + RCC_Clocks->ADCCLK_Frequency = RCC_Clocks->PCLK_Frequency >> 1; + } + else + { + /* ADC Clock is derived from PCLK/4 */ + RCC_Clocks->ADCCLK_Frequency = RCC_Clocks->PCLK_Frequency >> 2; + } + + } + + /* CECCLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_CECSW) != RCC_CFGR3_CECSW) + { + /* CEC Clock is HSI/244 */ + RCC_Clocks->CECCLK_Frequency = HSI_VALUE / 244; + } + else + { + /* CECC Clock is LSE Osc. */ + RCC_Clocks->CECCLK_Frequency = LSE_VALUE; + } + + /* I2C1CLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_I2C1SW) != RCC_CFGR3_I2C1SW) + { + /* I2C1 Clock is HSI Osc. */ + RCC_Clocks->I2C1CLK_Frequency = HSI_VALUE; + } + else + { + /* I2C1 Clock is System Clock */ + RCC_Clocks->I2C1CLK_Frequency = RCC_Clocks->SYSCLK_Frequency; + } + + /* USART1CLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_USART1SW) == 0x0) + { + /* USART1 Clock is PCLK */ + RCC_Clocks->USART1CLK_Frequency = RCC_Clocks->PCLK_Frequency; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART1SW) == RCC_CFGR3_USART1SW_0) + { + /* USART1 Clock is System Clock */ + RCC_Clocks->USART1CLK_Frequency = RCC_Clocks->SYSCLK_Frequency; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART1SW) == RCC_CFGR3_USART1SW_1) + { + /* USART1 Clock is LSE Osc. */ + RCC_Clocks->USART1CLK_Frequency = LSE_VALUE; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART1SW) == RCC_CFGR3_USART1SW) + { + /* USART1 Clock is HSI Osc. */ + RCC_Clocks->USART1CLK_Frequency = HSI_VALUE; + } + + /* USART2CLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_USART2SW) == 0x0) + { + /* USART Clock is PCLK */ + RCC_Clocks->USART2CLK_Frequency = RCC_Clocks->PCLK_Frequency; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART2SW) == RCC_CFGR3_USART2SW_0) + { + /* USART Clock is System Clock */ + RCC_Clocks->USART2CLK_Frequency = RCC_Clocks->SYSCLK_Frequency; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART2SW) == RCC_CFGR3_USART2SW_1) + { + /* USART Clock is LSE Osc. */ + RCC_Clocks->USART2CLK_Frequency = LSE_VALUE; + } + else if((RCC->CFGR3 & RCC_CFGR3_USART2SW) == RCC_CFGR3_USART2SW) + { + /* USART Clock is HSI Osc. */ + RCC_Clocks->USART2CLK_Frequency = HSI_VALUE; + } + + /* USBCLK clock frequency */ + if((RCC->CFGR3 & RCC_CFGR3_USBSW) != RCC_CFGR3_USBSW) + { + /* USB Clock is HSI48 */ + RCC_Clocks->USBCLK_Frequency = HSI48_VALUE; + } + else + { + /* USB Clock is PLL clock */ + RCC_Clocks->USBCLK_Frequency = pllclk; + } +} + +/** + * @} + */ + +/** @defgroup RCC_Group3 Peripheral clocks configuration functions + * @brief Peripheral clocks configuration functions + * +@verbatim + =============================================================================== + #####Peripheral clocks configuration functions ##### + =============================================================================== + + [..] This section provide functions allowing to configure the Peripheral clocks. + (#) The RTC clock which is derived from the LSE, LSI or HSE_Div32 (HSE + divided by 32). + (#) After restart from Reset or wakeup from STANDBY, all peripherals are off + except internal SRAM, Flash and SWD. Before to start using a peripheral you + have to enable its interface clock. You can do this using RCC_AHBPeriphClockCmd(), + RCC_APB2PeriphClockCmd() and RCC_APB1PeriphClockCmd() functions. + (#) To reset the peripherals configuration (to the default state after device reset) + you can use RCC_AHBPeriphResetCmd(), RCC_APB2PeriphResetCmd() and + RCC_APB1PeriphResetCmd() functions. + +@endverbatim + * @{ + */ + +/** + * @brief Configures the RTC clock (RTCCLK). + * @note As the RTC clock configuration bits are in the Backup domain and write + * access is denied to this domain after reset, you have to enable write + * access using PWR_BackupAccessCmd(ENABLE) function before to configure + * the RTC clock source (to be done once after reset). + * @note Once the RTC clock is configured it can't be changed unless the RTC + * is reset using RCC_BackupResetCmd function, or by a Power On Reset (POR) + * + * @param RCC_RTCCLKSource: specifies the RTC clock source. + * This parameter can be one of the following values: + * @arg RCC_RTCCLKSource_LSE: LSE selected as RTC clock + * @arg RCC_RTCCLKSource_LSI: LSI selected as RTC clock + * @arg RCC_RTCCLKSource_HSE_Div32: HSE divided by 32 selected as RTC clock + * + * @note If the LSE or LSI is used as RTC clock source, the RTC continues to + * work in STOP and STANDBY modes, and can be used as wakeup source. + * However, when the HSE clock is used as RTC clock source, the RTC + * cannot be used in STOP and STANDBY modes. + * + * @note The maximum input clock frequency for RTC is 2MHz (when using HSE as + * RTC clock source). + * + * @retval None + */ +void RCC_RTCCLKConfig(uint32_t RCC_RTCCLKSource) +{ + /* Check the parameters */ + assert_param(IS_RCC_RTCCLK_SOURCE(RCC_RTCCLKSource)); + + /* Select the RTC clock source */ + RCC->BDCR |= RCC_RTCCLKSource; +} + +/** + * @brief Enables or disables the RTC clock. + * @note This function must be used only after the RTC clock source was selected + * using the RCC_RTCCLKConfig function. + * @param NewState: new state of the RTC clock. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_RTCCLKCmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->BDCR |= RCC_BDCR_RTCEN; + } + else + { + RCC->BDCR &= ~RCC_BDCR_RTCEN; + } +} + +/** + * @brief Forces or releases the Backup domain reset. + * @note This function resets the RTC peripheral (including the backup registers) + * and the RTC clock source selection in RCC_BDCR register. + * @param NewState: new state of the Backup domain reset. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_BackupResetCmd(FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->BDCR |= RCC_BDCR_BDRST; + } + else + { + RCC->BDCR &= ~RCC_BDCR_BDRST; + } +} + +/** + * @brief Enables or disables the AHB peripheral clock. + * @note After reset, the peripheral clock (used for registers read/write access) + * is disabled and the application software has to enable this clock before + * using it. + * @param RCC_AHBPeriph: specifies the AHB peripheral to gates its clock. + * This parameter can be any combination of the following values: + * @arg RCC_AHBPeriph_GPIOA: GPIOA clock + * @arg RCC_AHBPeriph_GPIOB: GPIOB clock + * @arg RCC_AHBPeriph_GPIOC: GPIOC clock + * @arg RCC_AHBPeriph_GPIOD: GPIOD clock + * @arg RCC_AHBPeriph_GPIOE: GPIOE clock, applicable only for STM32F072 devices + * @arg RCC_AHBPeriph_GPIOF: GPIOF clock + * @arg RCC_AHBPeriph_TS: TS clock + * @arg RCC_AHBPeriph_CRC: CRC clock + * @arg RCC_AHBPeriph_FLITF: (has effect only when the Flash memory is in power down mode) + * @arg RCC_AHBPeriph_SRAM: SRAM clock + * @arg RCC_AHBPeriph_DMA1: DMA1 clock + * @param NewState: new state of the specified peripheral clock. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_AHBPeriphClockCmd(uint32_t RCC_AHBPeriph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_AHB_PERIPH(RCC_AHBPeriph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->AHBENR |= RCC_AHBPeriph; + } + else + { + RCC->AHBENR &= ~RCC_AHBPeriph; + } +} + +/** + * @brief Enables or disables the High Speed APB (APB2) peripheral clock. + * @note After reset, the peripheral clock (used for registers read/write access) + * is disabled and the application software has to enable this clock before + * using it. + * @param RCC_APB2Periph: specifies the APB2 peripheral to gates its clock. + * This parameter can be any combination of the following values: + * @arg RCC_APB2Periph_SYSCFG: SYSCFG clock + * @arg RCC_APB2Periph_ADC1: ADC1 clock + * @arg RCC_APB2Periph_TIM1: TIM1 clock + * @arg RCC_APB2Periph_SPI1: SPI1 clock + * @arg RCC_APB2Periph_USART1: USART1 clock + * @arg RCC_APB2Periph_TIM15: TIM15 clock + * @arg RCC_APB2Periph_TIM16: TIM16 clock + * @arg RCC_APB2Periph_TIM17: TIM17 clock + * @arg RCC_APB2Periph_DBGMCU: DBGMCU clock + * @param NewState: new state of the specified peripheral clock. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_APB2PeriphClockCmd(uint32_t RCC_APB2Periph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_APB2_PERIPH(RCC_APB2Periph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->APB2ENR |= RCC_APB2Periph; + } + else + { + RCC->APB2ENR &= ~RCC_APB2Periph; + } +} + +/** + * @brief Enables or disables the Low Speed APB (APB1) peripheral clock. + * @note After reset, the peripheral clock (used for registers read/write access) + * is disabled and the application software has to enable this clock before + * using it. + * @param RCC_APB1Periph: specifies the APB1 peripheral to gates its clock. + * This parameter can be any combination of the following values: + * @arg RCC_APB1Periph_TIM2: TIM2 clock, applicable only for STM32F051 and STM32F072 devices + * @arg RCC_APB1Periph_TIM3: TIM3 clock + * @arg RCC_APB1Periph_TIM6: TIM6 clock + * @arg RCC_APB1Periph_TIM7: TIM7 clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_TIM14: TIM14 clock + * @arg RCC_APB1Periph_WWDG: WWDG clock + * @arg RCC_APB1Periph_SPI2: SPI2 clock + * @arg RCC_APB1Periph_USART2: USART2 clock + * @arg RCC_APB1Periph_USART3: USART3 clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_USART4: USART4 clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_I2C1: I2C1 clock + * @arg RCC_APB1Periph_I2C2: I2C2 clock + * @arg RCC_APB1Periph_USB: USB clock, applicable only for STM32F042 and STM32F072 devices + * @arg RCC_APB1Periph_CAN: CAN clock, applicable only for STM32F042 and STM32F072 devices + * @arg RCC_APB1Periph_CRS: CRS clock , applicable only for STM32F042 and STM32F072 devices + * @arg RCC_APB1Periph_PWR: PWR clock + * @arg RCC_APB1Periph_DAC: DAC clock, applicable only for STM32F051 and STM32F072 devices + * @arg RCC_APB1Periph_CEC: CEC clock, applicable only for STM32F051, STM32F042 and STM32F072 devices + * @param NewState: new state of the specified peripheral clock. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_APB1PeriphClockCmd(uint32_t RCC_APB1Periph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_APB1_PERIPH(RCC_APB1Periph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->APB1ENR |= RCC_APB1Periph; + } + else + { + RCC->APB1ENR &= ~RCC_APB1Periph; + } +} + +/** + * @brief Forces or releases AHB peripheral reset. + * @param RCC_AHBPeriph: specifies the AHB peripheral to reset. + * This parameter can be any combination of the following values: + * @arg RCC_AHBPeriph_GPIOA: GPIOA clock + * @arg RCC_AHBPeriph_GPIOB: GPIOB clock + * @arg RCC_AHBPeriph_GPIOC: GPIOC clock + * @arg RCC_AHBPeriph_GPIOD: GPIOD clock + * @arg RCC_AHBPeriph_GPIOE: GPIOE clock, applicable only for STM32F072 devices + * @arg RCC_AHBPeriph_GPIOF: GPIOF clock + * @arg RCC_AHBPeriph_TS: TS clock + * @param NewState: new state of the specified peripheral reset. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_AHBPeriphResetCmd(uint32_t RCC_AHBPeriph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_AHB_RST_PERIPH(RCC_AHBPeriph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->AHBRSTR |= RCC_AHBPeriph; + } + else + { + RCC->AHBRSTR &= ~RCC_AHBPeriph; + } +} + +/** + * @brief Forces or releases High Speed APB (APB2) peripheral reset. + * @param RCC_APB2Periph: specifies the APB2 peripheral to reset. + * This parameter can be any combination of the following values: + * @arg RCC_APB2Periph_SYSCFG: SYSCFG clock + * @arg RCC_APB2Periph_ADC1: ADC1 clock + * @arg RCC_APB2Periph_TIM1: TIM1 clock + * @arg RCC_APB2Periph_SPI1: SPI1 clock + * @arg RCC_APB2Periph_USART1: USART1 clock + * @arg RCC_APB2Periph_TIM15: TIM15 clock + * @arg RCC_APB2Periph_TIM16: TIM16 clock + * @arg RCC_APB2Periph_TIM17: TIM17 clock + * @arg RCC_APB2Periph_DBGMCU: DBGMCU clock + * @param NewState: new state of the specified peripheral reset. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_APB2PeriphResetCmd(uint32_t RCC_APB2Periph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_APB2_PERIPH(RCC_APB2Periph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->APB2RSTR |= RCC_APB2Periph; + } + else + { + RCC->APB2RSTR &= ~RCC_APB2Periph; + } +} + +/** + * @brief Forces or releases Low Speed APB (APB1) peripheral reset. + * @param RCC_APB1Periph: specifies the APB1 peripheral to reset. + * This parameter can be any combination of the following values: + * @arg RCC_APB1Periph_TIM2: TIM2 clock, applicable only for STM32F051 and STM32F072 devices + * @arg RCC_APB1Periph_TIM3: TIM3 clock + * @arg RCC_APB1Periph_TIM6: TIM6 clock + * @arg RCC_APB1Periph_TIM7: TIM7 clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_TIM14: TIM14 clock + * @arg RCC_APB1Periph_WWDG: WWDG clock + * @arg RCC_APB1Periph_SPI2: SPI2 clock + * @arg RCC_APB1Periph_USART2: USART2 clock + * @arg RCC_APB1Periph_USART3: USART3 clock + * @arg RCC_APB1Periph_USART4: USART4 clock + * @arg RCC_APB1Periph_I2C1: I2C1 clock + * @arg RCC_APB1Periph_I2C2: I2C2 clock + * @arg RCC_APB1Periph_USB: USB clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_CAN: CAN clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_CRS: CRS clock, applicable only for STM32F072 devices + * @arg RCC_APB1Periph_PWR: PWR clock + * @arg RCC_APB1Periph_DAC: DAC clock, applicable only for STM32F051 and STM32F072 devices + * @arg RCC_APB1Periph_CEC: CEC clock, applicable only for STM32F051 and STM32F072 devices + * @param NewState: new state of the specified peripheral clock. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_APB1PeriphResetCmd(uint32_t RCC_APB1Periph, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_APB1_PERIPH(RCC_APB1Periph)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + RCC->APB1RSTR |= RCC_APB1Periph; + } + else + { + RCC->APB1RSTR &= ~RCC_APB1Periph; + } +} + +/** + * @} + */ + +/** @defgroup RCC_Group4 Interrupts and flags management functions + * @brief Interrupts and flags management functions + * +@verbatim + =============================================================================== + ##### Interrupts and flags management functions ##### + =============================================================================== +@endverbatim + * @{ + */ + +/** + * @brief Enables or disables the specified RCC interrupts. + * @note The CSS interrupt doesn't have an enable bit; once the CSS is enabled + * and if the HSE clock fails, the CSS interrupt occurs and an NMI is + * automatically generated. The NMI will be executed indefinitely, and + * since NMI has higher priority than any other IRQ (and main program) + * the application will be stacked in the NMI ISR unless the CSS interrupt + * pending bit is cleared. + * @param RCC_IT: specifies the RCC interrupt sources to be enabled or disabled. + * This parameter can be any combination of the following values: + * @arg RCC_IT_LSIRDY: LSI ready interrupt + * @arg RCC_IT_LSERDY: LSE ready interrupt + * @arg RCC_IT_HSIRDY: HSI ready interrupt + * @arg RCC_IT_HSERDY: HSE ready interrupt + * @arg RCC_IT_PLLRDY: PLL ready interrupt + * @arg RCC_IT_HSI14RDY: HSI14 ready interrupt + * @arg RCC_IT_HSI48RDY: HSI48 ready interrupt, applicable only for STM32F072 devices + * @param NewState: new state of the specified RCC interrupts. + * This parameter can be: ENABLE or DISABLE. + * @retval None + */ +void RCC_ITConfig(uint8_t RCC_IT, FunctionalState NewState) +{ + /* Check the parameters */ + assert_param(IS_RCC_IT(RCC_IT)); + assert_param(IS_FUNCTIONAL_STATE(NewState)); + + if (NewState != DISABLE) + { + /* Perform Byte access to RCC_CIR[13:8] bits to enable the selected interrupts */ + *(__IO uint8_t *) CIR_BYTE1_ADDRESS |= RCC_IT; + } + else + { + /* Perform Byte access to RCC_CIR[13:8] bits to disable the selected interrupts */ + *(__IO uint8_t *) CIR_BYTE1_ADDRESS &= (uint8_t)~RCC_IT; + } +} + +/** + * @brief Checks whether the specified RCC flag is set or not. + * @param RCC_FLAG: specifies the flag to check. + * This parameter can be one of the following values: + * @arg RCC_FLAG_HSIRDY: HSI oscillator clock ready + * @arg RCC_FLAG_HSERDY: HSE oscillator clock ready + * @arg RCC_FLAG_PLLRDY: PLL clock ready + * @arg RCC_FLAG_LSERDY: LSE oscillator clock ready + * @arg RCC_FLAG_LSIRDY: LSI oscillator clock ready + * @arg RCC_FLAG_OBLRST: Option Byte Loader (OBL) reset + * @arg RCC_FLAG_PINRST: Pin reset + * @arg RCC_FLAG_V18PWRRSTF: V1.8 power domain reset + * @arg RCC_FLAG_PORRST: POR/PDR reset + * @arg RCC_FLAG_SFTRST: Software reset + * @arg RCC_FLAG_IWDGRST: Independent Watchdog reset + * @arg RCC_FLAG_WWDGRST: Window Watchdog reset + * @arg RCC_FLAG_LPWRRST: Low Power reset + * @arg RCC_FLAG_HSI14RDY: HSI14 oscillator clock ready + * @arg RCC_FLAG_HSI48RDY: HSI48 oscillator clock ready, applicable only for STM32F072 devices + * @retval The new state of RCC_FLAG (SET or RESET). + */ +FlagStatus RCC_GetFlagStatus(uint8_t RCC_FLAG) +{ + uint32_t tmp = 0; + uint32_t statusreg = 0; + FlagStatus bitstatus = RESET; + + /* Check the parameters */ + assert_param(IS_RCC_FLAG(RCC_FLAG)); + + /* Get the RCC register index */ + tmp = RCC_FLAG >> 5; + + if (tmp == 0) /* The flag to check is in CR register */ + { + statusreg = RCC->CR; + } + else if (tmp == 1) /* The flag to check is in BDCR register */ + { + statusreg = RCC->BDCR; + } + else if (tmp == 2) /* The flag to check is in CSR register */ + { + statusreg = RCC->CSR; + } + else /* The flag to check is in CR2 register */ + { + statusreg = RCC->CR2; + } + + /* Get the flag position */ + tmp = RCC_FLAG & FLAG_MASK; + + if ((statusreg & ((uint32_t)1 << tmp)) != (uint32_t)RESET) + { + bitstatus = SET; + } + else + { + bitstatus = RESET; + } + /* Return the flag status */ + return bitstatus; +} + +/** + * @brief Clears the RCC reset flags. + * The reset flags are: RCC_FLAG_OBLRST, RCC_FLAG_PINRST, RCC_FLAG_V18PWRRSTF, + * RCC_FLAG_PORRST, RCC_FLAG_SFTRST, RCC_FLAG_IWDGRST, RCC_FLAG_WWDGRST, + * RCC_FLAG_LPWRRST. + * @param None + * @retval None + */ +void RCC_ClearFlag(void) +{ + /* Set RMVF bit to clear the reset flags */ + RCC->CSR |= RCC_CSR_RMVF; +} + +/** + * @brief Checks whether the specified RCC interrupt has occurred or not. + * @param RCC_IT: specifies the RCC interrupt source to check. + * This parameter can be one of the following values: + * @arg RCC_IT_LSIRDY: LSI ready interrupt + * @arg RCC_IT_LSERDY: LSE ready interrupt + * @arg RCC_IT_HSIRDY: HSI ready interrupt + * @arg RCC_IT_HSERDY: HSE ready interrupt + * @arg RCC_IT_PLLRDY: PLL ready interrupt + * @arg RCC_IT_HSI14RDY: HSI14 ready interrupt + * @arg RCC_IT_HSI48RDY: HSI48 ready interrupt, applicable only for STM32F072 devices + * @arg RCC_IT_CSS: Clock Security System interrupt + * @retval The new state of RCC_IT (SET or RESET). + */ +ITStatus RCC_GetITStatus(uint8_t RCC_IT) +{ + ITStatus bitstatus = RESET; + + /* Check the parameters */ + assert_param(IS_RCC_GET_IT(RCC_IT)); + + /* Check the status of the specified RCC interrupt */ + if ((RCC->CIR & RCC_IT) != (uint32_t)RESET) + { + bitstatus = SET; + } + else + { + bitstatus = RESET; + } + /* Return the RCC_IT status */ + return bitstatus; +} + +/** + * @brief Clears the RCC's interrupt pending bits. + * @param RCC_IT: specifies the interrupt pending bit to clear. + * This parameter can be any combination of the following values: + * @arg RCC_IT_LSIRDY: LSI ready interrupt + * @arg RCC_IT_LSERDY: LSE ready interrupt + * @arg RCC_IT_HSIRDY: HSI ready interrupt + * @arg RCC_IT_HSERDY: HSE ready interrupt + * @arg RCC_IT_PLLRDY: PLL ready interrupt + * @arg RCC_IT_HSI48RDY: HSI48 ready interrupt, applicable only for STM32F072 devices + * @arg RCC_IT_HSI14RDY: HSI14 ready interrupt + * @arg RCC_IT_CSS: Clock Security System interrupt + * @retval None + */ +void RCC_ClearITPendingBit(uint8_t RCC_IT) +{ + /* Check the parameters */ + assert_param(IS_RCC_CLEAR_IT(RCC_IT)); + + /* Perform Byte access to RCC_CIR[23:16] bits to clear the selected interrupt + pending bits */ + *(__IO uint8_t *) CIR_BYTE2_ADDRESS = RCC_IT; +} + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ + +/** + * @} + */ + +/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/