| /** |
| ****************************************************************************** |
| * @file stm32l0xx_ll_usart.c |
| * @author MCD Application Team |
| * @brief USART LL module driver. |
| ****************************************************************************** |
| * @attention |
| * |
| * Copyright (c) 2016 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 "stm32l0xx_ll_usart.h" |
| #include "stm32l0xx_ll_rcc.h" |
| #include "stm32l0xx_ll_bus.h" |
| #ifdef USE_FULL_ASSERT |
| #include "stm32_assert.h" |
| #else |
| #define assert_param(expr) ((void)0U) |
| #endif /* USE_FULL_ASSERT */ |
| |
| /** @addtogroup STM32L0xx_LL_Driver |
| * @{ |
| */ |
| |
| #if defined (USART1) || defined (USART2) || defined (USART4) || defined (USART5) |
| |
| /** @addtogroup USART_LL |
| * @{ |
| */ |
| |
| /* Private types -------------------------------------------------------------*/ |
| /* Private variables ---------------------------------------------------------*/ |
| /* Private constants ---------------------------------------------------------*/ |
| /* Private macros ------------------------------------------------------------*/ |
| /** @addtogroup USART_LL_Private_Macros |
| * @{ |
| */ |
| |
| /* __BAUDRATE__ The maximum Baud Rate is derived from the maximum clock available |
| * divided by the smallest oversampling used on the USART (i.e. 8) */ |
| #define IS_LL_USART_BAUDRATE(__BAUDRATE__) ((__BAUDRATE__) <= 4000000U) |
| |
| /* __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 defined(USART1) |
| 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); |
| } |
| #endif /* USART1 */ |
| #if defined(USART1) |
| else if (USARTx == USART2) |
| #else |
| if (USARTx == USART2) |
| #endif /* USART1 */ |
| { |
| /* 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(USART4) |
| else if (USARTx == USART4) |
| { |
| /* Force reset of USART clock */ |
| LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_USART4); |
| |
| /* Release reset of USART clock */ |
| LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_USART4); |
| } |
| #endif /* USART4 */ |
| #if defined(USART5) |
| else if (USARTx == USART5) |
| { |
| /* Force reset of USART clock */ |
| LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_USART5); |
| |
| /* Release reset of USART clock */ |
| LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_USART5); |
| } |
| #endif /* USART5 */ |
| 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; |
| #if defined(USART4) || defined(USART5) |
| LL_RCC_ClocksTypeDef RCC_Clocks; |
| #endif /* USART4 || USART5 */ |
| |
| /* Check the parameters */ |
| assert_param(IS_UART_INSTANCE(USARTx)); |
| 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 defined(USART1) |
| if (USARTx == USART1) |
| { |
| periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART1_CLKSOURCE); |
| } |
| #endif /* USART1 */ |
| #if defined(USART1) |
| else if (USARTx == USART2) |
| #else |
| if (USARTx == USART2) |
| #endif /* USART1 */ |
| { |
| periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART2_CLKSOURCE); |
| } |
| #if defined(USART4) |
| else if (USARTx == USART4) |
| { |
| /* USART4 clock is PCLK1 */ |
| LL_RCC_GetSystemClocksFreq(&RCC_Clocks); |
| periphclk = RCC_Clocks.PCLK1_Frequency; |
| } |
| #endif /* USART4 */ |
| #if defined(USART5) |
| else if (USARTx == USART5) |
| { |
| /* USART5 clock is PCLK1 */ |
| LL_RCC_GetSystemClocksFreq(&RCC_Clocks); |
| periphclk = RCC_Clocks.PCLK1_Frequency; |
| } |
| #endif /* USART5 */ |
| else |
| { |
| /* Nothing to do, as error code is already assigned to ERROR value */ |
| } |
| |
| /* Configure the USART Baud Rate : |
| - 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, |
| USART_InitStruct->OverSampling, |
| USART_InitStruct->BaudRate); |
| |
| /* Check BRR is greater than or equal to 16d */ |
| assert_param(IS_LL_USART_BRR_MIN(USARTx->BRR)); |
| } |
| } |
| /* 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 */ |
| USART_InitStruct->BaudRate = 9600U; |
| 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 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); |
| } |
| } |
| /* 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 || USART4 || USART5 */ |
| |
| /** |
| * @} |
| */ |
| |
| #endif /* USE_FULL_LL_DRIVER */ |
