/** ****************************************************************************** * @file stm32l4xx_ll_usart.c * @author MCD Application Team * @brief USART LL module driver. ****************************************************************************** * @attention * * Copyright (c) 2017 STMicroelectronics. * All rights reserved. * * This software is licensed under terms that can be found in the LICENSE file * in the root directory of this software component. * If no LICENSE file comes with this software, it is provided AS-IS. * ****************************************************************************** */ #if defined(USE_FULL_LL_DRIVER) /* Includes ------------------------------------------------------------------*/ #include "stm32l4xx_ll_usart.h" #include "stm32l4xx_ll_rcc.h" #include "stm32l4xx_ll_bus.h" #ifdef USE_FULL_ASSERT #include "stm32_assert.h" #else #define assert_param(expr) ((void)0U) #endif /* USE_FULL_ASSERT */ /** @addtogroup STM32L4xx_LL_Driver * @{ */ #if defined(USART1) || defined(USART2) || defined(USART3) || defined(UART4) || defined(UART5) /** @addtogroup USART_LL * @{ */ /* Private types -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ /* Private constants ---------------------------------------------------------*/ /** @addtogroup USART_LL_Private_Constants * @{ */ /* Definition of default baudrate value used for USART initialisation */ #define USART_DEFAULT_BAUDRATE (9600U) /** * @} */ /* Private macros ------------------------------------------------------------*/ /** @addtogroup USART_LL_Private_Macros * @{ */ #if defined(USART_PRESC_PRESCALER) #define IS_LL_USART_PRESCALER(__VALUE__) (((__VALUE__) == LL_USART_PRESCALER_DIV1) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV2) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV4) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV6) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV8) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV10) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV12) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV16) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV32) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV64) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV128) \ || ((__VALUE__) == LL_USART_PRESCALER_DIV256)) #endif /* USART_PRESC_PRESCALER */ /* __BAUDRATE__ The maximum Baud Rate is derived from the maximum clock available * divided by the smallest oversampling used on the USART (i.e. 8) */ #if defined(STM32L4R5xx) || defined(STM32L4R7xx) || defined(STM32L4R9xx) || defined(STM32L4S5xx) || defined(STM32L4S7xx) || defined(STM32L4S9xx) #define IS_LL_USART_BAUDRATE(__BAUDRATE__) ((__BAUDRATE__) <= 15000000U) #else #define IS_LL_USART_BAUDRATE(__BAUDRATE__) ((__BAUDRATE__) <= 10000000U) #endif /* STM32L4R5xx || STM32L4R7xx || STM32L4R9xx || STM32L4S5xx || STM32L4S7xx || STM32L4S9xx */ /* __VALUE__ In case of oversampling by 16 and 8, BRR content must be greater than or equal to 16d. */ #define IS_LL_USART_BRR_MIN(__VALUE__) ((__VALUE__) >= 16U) #define IS_LL_USART_DIRECTION(__VALUE__) (((__VALUE__) == LL_USART_DIRECTION_NONE) \ || ((__VALUE__) == LL_USART_DIRECTION_RX) \ || ((__VALUE__) == LL_USART_DIRECTION_TX) \ || ((__VALUE__) == LL_USART_DIRECTION_TX_RX)) #define IS_LL_USART_PARITY(__VALUE__) (((__VALUE__) == LL_USART_PARITY_NONE) \ || ((__VALUE__) == LL_USART_PARITY_EVEN) \ || ((__VALUE__) == LL_USART_PARITY_ODD)) #define IS_LL_USART_DATAWIDTH(__VALUE__) (((__VALUE__) == LL_USART_DATAWIDTH_7B) \ || ((__VALUE__) == LL_USART_DATAWIDTH_8B) \ || ((__VALUE__) == LL_USART_DATAWIDTH_9B)) #define IS_LL_USART_OVERSAMPLING(__VALUE__) (((__VALUE__) == LL_USART_OVERSAMPLING_16) \ || ((__VALUE__) == LL_USART_OVERSAMPLING_8)) #define IS_LL_USART_LASTBITCLKOUTPUT(__VALUE__) (((__VALUE__) == LL_USART_LASTCLKPULSE_NO_OUTPUT) \ || ((__VALUE__) == LL_USART_LASTCLKPULSE_OUTPUT)) #define IS_LL_USART_CLOCKPHASE(__VALUE__) (((__VALUE__) == LL_USART_PHASE_1EDGE) \ || ((__VALUE__) == LL_USART_PHASE_2EDGE)) #define IS_LL_USART_CLOCKPOLARITY(__VALUE__) (((__VALUE__) == LL_USART_POLARITY_LOW) \ || ((__VALUE__) == LL_USART_POLARITY_HIGH)) #define IS_LL_USART_CLOCKOUTPUT(__VALUE__) (((__VALUE__) == LL_USART_CLOCK_DISABLE) \ || ((__VALUE__) == LL_USART_CLOCK_ENABLE)) #define IS_LL_USART_STOPBITS(__VALUE__) (((__VALUE__) == LL_USART_STOPBITS_0_5) \ || ((__VALUE__) == LL_USART_STOPBITS_1) \ || ((__VALUE__) == LL_USART_STOPBITS_1_5) \ || ((__VALUE__) == LL_USART_STOPBITS_2)) #define IS_LL_USART_HWCONTROL(__VALUE__) (((__VALUE__) == LL_USART_HWCONTROL_NONE) \ || ((__VALUE__) == LL_USART_HWCONTROL_RTS) \ || ((__VALUE__) == LL_USART_HWCONTROL_CTS) \ || ((__VALUE__) == LL_USART_HWCONTROL_RTS_CTS)) /** * @} */ /* Private function prototypes -----------------------------------------------*/ /* Exported functions --------------------------------------------------------*/ /** @addtogroup USART_LL_Exported_Functions * @{ */ /** @addtogroup USART_LL_EF_Init * @{ */ /** * @brief De-initialize USART registers (Registers restored to their default values). * @param USARTx USART Instance * @retval An ErrorStatus enumeration value: * - SUCCESS: USART registers are de-initialized * - ERROR: USART registers are not de-initialized */ ErrorStatus LL_USART_DeInit(const USART_TypeDef *USARTx) { ErrorStatus status = SUCCESS; /* Check the parameters */ assert_param(IS_UART_INSTANCE(USARTx)); if (USARTx == USART1) { /* Force reset of USART clock */ LL_APB2_GRP1_ForceReset(LL_APB2_GRP1_PERIPH_USART1); /* Release reset of USART clock */ LL_APB2_GRP1_ReleaseReset(LL_APB2_GRP1_PERIPH_USART1); } else if (USARTx == USART2) { /* Force reset of USART clock */ LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_USART2); /* Release reset of USART clock */ LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_USART2); } #if defined(USART3) else if (USARTx == USART3) { /* Force reset of USART clock */ LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_USART3); /* Release reset of USART clock */ LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_USART3); } #endif /* USART3 */ #if defined(UART4) else if (USARTx == UART4) { /* Force reset of UART clock */ LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_UART4); /* Release reset of UART clock */ LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_UART4); } #endif /* UART4 */ #if defined(UART5) else if (USARTx == UART5) { /* Force reset of UART clock */ LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_UART5); /* Release reset of UART clock */ LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_UART5); } #endif /* UART5 */ else { status = ERROR; } return (status); } /** * @brief Initialize USART registers according to the specified * parameters in USART_InitStruct. * @note As some bits in USART configuration registers can only be written when * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling * this function. Otherwise, ERROR result will be returned. * @note Baud rate value stored in USART_InitStruct BaudRate field, should be valid (different from 0). * @param USARTx USART Instance * @param USART_InitStruct pointer to a LL_USART_InitTypeDef structure * that contains the configuration information for the specified USART peripheral. * @retval An ErrorStatus enumeration value: * - SUCCESS: USART registers are initialized according to USART_InitStruct content * - ERROR: Problem occurred during USART Registers initialization */ ErrorStatus LL_USART_Init(USART_TypeDef *USARTx, const LL_USART_InitTypeDef *USART_InitStruct) { ErrorStatus status = ERROR; uint32_t periphclk = LL_RCC_PERIPH_FREQUENCY_NO; /* Check the parameters */ assert_param(IS_UART_INSTANCE(USARTx)); #if defined(USART_PRESC_PRESCALER) assert_param(IS_LL_USART_PRESCALER(USART_InitStruct->PrescalerValue)); #endif /* USART_PRESC_PRESCALER */ assert_param(IS_LL_USART_BAUDRATE(USART_InitStruct->BaudRate)); assert_param(IS_LL_USART_DATAWIDTH(USART_InitStruct->DataWidth)); assert_param(IS_LL_USART_STOPBITS(USART_InitStruct->StopBits)); assert_param(IS_LL_USART_PARITY(USART_InitStruct->Parity)); assert_param(IS_LL_USART_DIRECTION(USART_InitStruct->TransferDirection)); assert_param(IS_LL_USART_HWCONTROL(USART_InitStruct->HardwareFlowControl)); assert_param(IS_LL_USART_OVERSAMPLING(USART_InitStruct->OverSampling)); /* USART needs to be in disabled state, in order to be able to configure some bits in CRx registers */ if (LL_USART_IsEnabled(USARTx) == 0U) { /*---------------------------- USART CR1 Configuration --------------------- * Configure USARTx CR1 (USART Word Length, Parity, Mode and Oversampling bits) with parameters: * - DataWidth: USART_CR1_M bits according to USART_InitStruct->DataWidth value * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to USART_InitStruct->Parity value * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to USART_InitStruct->TransferDirection value * - Oversampling: USART_CR1_OVER8 bit according to USART_InitStruct->OverSampling value. */ MODIFY_REG(USARTx->CR1, (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS | USART_CR1_TE | USART_CR1_RE | USART_CR1_OVER8), (USART_InitStruct->DataWidth | USART_InitStruct->Parity | USART_InitStruct->TransferDirection | USART_InitStruct->OverSampling)); /*---------------------------- USART CR2 Configuration --------------------- * Configure USARTx CR2 (Stop bits) with parameters: * - Stop Bits: USART_CR2_STOP bits according to USART_InitStruct->StopBits value. * - CLKEN, CPOL, CPHA and LBCL bits are to be configured using LL_USART_ClockInit(). */ LL_USART_SetStopBitsLength(USARTx, USART_InitStruct->StopBits); /*---------------------------- USART CR3 Configuration --------------------- * Configure USARTx CR3 (Hardware Flow Control) with parameters: * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according to * USART_InitStruct->HardwareFlowControl value. */ LL_USART_SetHWFlowCtrl(USARTx, USART_InitStruct->HardwareFlowControl); /*---------------------------- USART BRR Configuration --------------------- * Retrieve Clock frequency used for USART Peripheral */ if (USARTx == USART1) { periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART1_CLKSOURCE); } else if (USARTx == USART2) { periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART2_CLKSOURCE); } #if defined(USART3) else if (USARTx == USART3) { periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART3_CLKSOURCE); } #endif /* USART3 */ #if defined(UART4) else if (USARTx == UART4) { periphclk = LL_RCC_GetUARTClockFreq(LL_RCC_UART4_CLKSOURCE); } #endif /* UART4 */ #if defined(UART5) else if (USARTx == UART5) { periphclk = LL_RCC_GetUARTClockFreq(LL_RCC_UART5_CLKSOURCE); } #endif /* UART5 */ else { /* Nothing to do, as error code is already assigned to ERROR value */ } /* Configure the USART Baud Rate : #if defined(USART_PRESC_PRESCALER) - prescaler value is required #endif - valid baud rate value (different from 0) is required - Peripheral clock as returned by RCC service, should be valid (different from 0). */ if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO) && (USART_InitStruct->BaudRate != 0U)) { status = SUCCESS; LL_USART_SetBaudRate(USARTx, periphclk, #if defined(USART_PRESC_PRESCALER) USART_InitStruct->PrescalerValue, #endif /* USART_PRESC_PRESCALER */ USART_InitStruct->OverSampling, USART_InitStruct->BaudRate); /* Check BRR is greater than or equal to 16d */ assert_param(IS_LL_USART_BRR_MIN(USARTx->BRR)); } #if defined(USART_PRESC_PRESCALER) /*---------------------------- USART PRESC Configuration ----------------------- * Configure USARTx PRESC (Prescaler) with parameters: * - PrescalerValue: USART_PRESC_PRESCALER bits according to USART_InitStruct->PrescalerValue value. */ LL_USART_SetPrescaler(USARTx, USART_InitStruct->PrescalerValue); #endif /* USART_PRESC_PRESCALER */ } /* Endif (=> USART not in Disabled state => return ERROR) */ return (status); } /** * @brief Set each @ref LL_USART_InitTypeDef field to default value. * @param USART_InitStruct pointer to a @ref LL_USART_InitTypeDef structure * whose fields will be set to default values. * @retval None */ void LL_USART_StructInit(LL_USART_InitTypeDef *USART_InitStruct) { /* Set USART_InitStruct fields to default values */ #if defined(USART_PRESC_PRESCALER) USART_InitStruct->PrescalerValue = LL_USART_PRESCALER_DIV1; #endif /* USART_PRESC_PRESCALER */ USART_InitStruct->BaudRate = USART_DEFAULT_BAUDRATE; USART_InitStruct->DataWidth = LL_USART_DATAWIDTH_8B; USART_InitStruct->StopBits = LL_USART_STOPBITS_1; USART_InitStruct->Parity = LL_USART_PARITY_NONE ; USART_InitStruct->TransferDirection = LL_USART_DIRECTION_TX_RX; USART_InitStruct->HardwareFlowControl = LL_USART_HWCONTROL_NONE; USART_InitStruct->OverSampling = LL_USART_OVERSAMPLING_16; } /** * @brief Initialize USART Clock related settings according to the * specified parameters in the USART_ClockInitStruct. * @note As some bits in USART configuration registers can only be written when * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling * this function. Otherwise, ERROR result will be returned. * @param USARTx USART Instance * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure * that contains the Clock configuration information for the specified USART peripheral. * @retval An ErrorStatus enumeration value: * - SUCCESS: USART registers related to Clock settings are initialized according * to USART_ClockInitStruct content * - ERROR: Problem occurred during USART Registers initialization */ ErrorStatus LL_USART_ClockInit(USART_TypeDef *USARTx, const LL_USART_ClockInitTypeDef *USART_ClockInitStruct) { ErrorStatus status = SUCCESS; /* Check USART Instance and Clock signal output parameters */ assert_param(IS_UART_INSTANCE(USARTx)); assert_param(IS_LL_USART_CLOCKOUTPUT(USART_ClockInitStruct->ClockOutput)); /* USART needs to be in disabled state, in order to be able to configure some bits in CRx registers */ if (LL_USART_IsEnabled(USARTx) == 0U) { #if defined(USART_CR2_SLVEN) /* Ensure USART instance is USART capable */ assert_param(IS_USART_INSTANCE(USARTx)); /* Check clock related parameters */ assert_param(IS_LL_USART_CLOCKPOLARITY(USART_ClockInitStruct->ClockPolarity)); assert_param(IS_LL_USART_CLOCKPHASE(USART_ClockInitStruct->ClockPhase)); assert_param(IS_LL_USART_LASTBITCLKOUTPUT(USART_ClockInitStruct->LastBitClockPulse)); /*---------------------------- USART CR2 Configuration ----------------------- * Configure USARTx CR2 (Clock signal related bits) with parameters: * - Clock Output: USART_CR2_CLKEN bit according to USART_ClockInitStruct->ClockOutput value * - Clock Polarity: USART_CR2_CPOL bit according to USART_ClockInitStruct->ClockPolarity value * - Clock Phase: USART_CR2_CPHA bit according to USART_ClockInitStruct->ClockPhase value * - Last Bit Clock Pulse Output: USART_CR2_LBCL bit according to USART_ClockInitStruct->LastBitClockPulse value. */ MODIFY_REG(USARTx->CR2, USART_CR2_CLKEN | USART_CR2_CPHA | USART_CR2_CPOL | USART_CR2_LBCL, USART_ClockInitStruct->ClockOutput | USART_ClockInitStruct->ClockPolarity | USART_ClockInitStruct->ClockPhase | USART_ClockInitStruct->LastBitClockPulse); #else /* If USART Clock signal is disabled */ if (USART_ClockInitStruct->ClockOutput == LL_USART_CLOCK_DISABLE) { /* Deactivate Clock signal delivery : * - Disable Clock Output: USART_CR2_CLKEN cleared */ LL_USART_DisableSCLKOutput(USARTx); } else { /* Ensure USART instance is USART capable */ assert_param(IS_USART_INSTANCE(USARTx)); /* Check clock related parameters */ assert_param(IS_LL_USART_CLOCKPOLARITY(USART_ClockInitStruct->ClockPolarity)); assert_param(IS_LL_USART_CLOCKPHASE(USART_ClockInitStruct->ClockPhase)); assert_param(IS_LL_USART_LASTBITCLKOUTPUT(USART_ClockInitStruct->LastBitClockPulse)); /*---------------------------- USART CR2 Configuration ----------------------- * Configure USARTx CR2 (Clock signal related bits) with parameters: * - Enable Clock Output: USART_CR2_CLKEN set * - Clock Polarity: USART_CR2_CPOL bit according to USART_ClockInitStruct->ClockPolarity value * - Clock Phase: USART_CR2_CPHA bit according to USART_ClockInitStruct->ClockPhase value * - Last Bit Clock Pulse Output: USART_CR2_LBCL bit according to USART_ClockInitStruct->LastBitClockPulse value. */ MODIFY_REG(USARTx->CR2, USART_CR2_CLKEN | USART_CR2_CPHA | USART_CR2_CPOL | USART_CR2_LBCL, USART_CR2_CLKEN | USART_ClockInitStruct->ClockPolarity | USART_ClockInitStruct->ClockPhase | USART_ClockInitStruct->LastBitClockPulse); } #endif /* USART_CR2_SLVEN */ } /* Else (USART not in Disabled state => return ERROR */ else { status = ERROR; } return (status); } /** * @brief Set each field of a @ref LL_USART_ClockInitTypeDef type structure to default value. * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure * whose fields will be set to default values. * @retval None */ void LL_USART_ClockStructInit(LL_USART_ClockInitTypeDef *USART_ClockInitStruct) { /* Set LL_USART_ClockInitStruct fields with default values */ USART_ClockInitStruct->ClockOutput = LL_USART_CLOCK_DISABLE; USART_ClockInitStruct->ClockPolarity = LL_USART_POLARITY_LOW; /* Not relevant when ClockOutput = LL_USART_CLOCK_DISABLE */ USART_ClockInitStruct->ClockPhase = LL_USART_PHASE_1EDGE; /* Not relevant when ClockOutput = LL_USART_CLOCK_DISABLE */ USART_ClockInitStruct->LastBitClockPulse = LL_USART_LASTCLKPULSE_NO_OUTPUT; /* Not relevant when ClockOutput = LL_USART_CLOCK_DISABLE */ } /** * @} */ /** * @} */ /** * @} */ #endif /* USART1 || USART2 || USART3 || UART4 || UART5 */ /** * @} */ #endif /* USE_FULL_LL_DRIVER */