--- /dev/null
+/**
+ ******************************************************************************
+ * @file stm32f4xx_usart.c
+ * @author MCD Application Team
+ * @version V1.0.0RC1
+ * @date 25-August-2011
+ * @brief This file provides firmware functions to manage the following
+ * functionalities of the Universal synchronous asynchronous receiver
+ * transmitter (USART):
+ * - Initialization and Configuration
+ * - Data transfers
+ * - Multi-Processor Communication
+ * - LIN mode
+ * - Half-duplex mode
+ * - Smartcard mode
+ * - IrDA mode
+ * - DMA transfers management
+ * - Interrupts and flags management
+ *
+ * @verbatim
+ *
+ * ===================================================================
+ * How to use this driver
+ * ===================================================================
+ * 1. Enable peripheral clock using the follwoing functions
+ * RCC_APB2PeriphClockCmd(RCC_APB2Periph_USARTx, ENABLE) for USART1 and USART6
+ * RCC_APB1PeriphClockCmd(RCC_APB1Periph_USARTx, ENABLE) for USART2, USART3, UART4 or UART5.
+ *
+ * 2. According to the USART mode, enable the GPIO clocks using
+ * RCC_AHB1PeriphClockCmd() function. (The I/O can be TX, RX, CTS,
+ * or/and SCLK).
+ *
+ * 3. Peripheral's alternate function:
+ * - Connect the pin to the desired peripherals' Alternate
+ * Function (AF) using GPIO_PinAFConfig() function
+ * - Configure the desired pin in alternate function by:
+ * GPIO_InitStruct->GPIO_Mode = GPIO_Mode_AF
+ * - Select the type, pull-up/pull-down and output speed via
+ * GPIO_PuPd, GPIO_OType and GPIO_Speed members
+ * - Call GPIO_Init() function
+ *
+ * 4. Program the Baud Rate, Word Length , Stop Bit, Parity, Hardware
+ * flow control and Mode(Receiver/Transmitter) using the USART_Init()
+ * function.
+ *
+ * 5. For synchronous mode, enable the clock and program the polarity,
+ * phase and last bit using the USART_ClockInit() function.
+ *
+ * 5. Enable the NVIC and the corresponding interrupt using the function
+ * USART_ITConfig() if you need to use interrupt mode.
+ *
+ * 6. When using the DMA mode
+ * - Configure the DMA using DMA_Init() function
+ * - Active the needed channel Request using USART_DMACmd() function
+ *
+ * 7. Enable the USART using the USART_Cmd() function.
+ *
+ * 8. Enable the DMA using the DMA_Cmd() function, when using DMA mode.
+ *
+ * Refer to Multi-Processor, LIN, half-duplex, Smartcard, IrDA sub-sections
+ * for more details
+ *
+ * In order to reach higher communication baudrates, it is possible to
+ * enable the oversampling by 8 mode using the function USART_OverSampling8Cmd().
+ * This function should be called after enabling the USART clock (RCC_APBxPeriphClockCmd())
+ * and before calling the function USART_Init().
+ *
+ * @endverbatim
+ *
+ ******************************************************************************
+ * @attention
+ *
+ * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
+ * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
+ * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
+ * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
+ * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
+ * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
+ *
+ * <h2><center>© COPYRIGHT 2011 STMicroelectronics</center></h2>
+ ******************************************************************************
+ */
+
+/* Includes ------------------------------------------------------------------*/
+#include "stm32f4xx_usart.h"
+#include "stm32f4xx_rcc.h"
+
+/** @addtogroup STM32F4xx_StdPeriph_Driver
+ * @{
+ */
+
+/** @defgroup USART
+ * @brief USART driver modules
+ * @{
+ */
+
+/* Private typedef -----------------------------------------------------------*/
+/* Private define ------------------------------------------------------------*/
+
+/*!< USART CR1 register clear Mask ((~(uint16_t)0xE9F3)) */
+#define CR1_CLEAR_MASK ((uint16_t)(USART_CR1_M | USART_CR1_PCE | \
+ USART_CR1_PS | USART_CR1_TE | \
+ USART_CR1_RE))
+
+/*!< USART CR2 register clock bits clear Mask ((~(uint16_t)0xF0FF)) */
+#define CR2_CLOCK_CLEAR_MASK ((uint16_t)(USART_CR2_CLKEN | USART_CR2_CPOL | \
+ USART_CR2_CPHA | USART_CR2_LBCL))
+
+/*!< USART CR3 register clear Mask ((~(uint16_t)0xFCFF)) */
+#define CR3_CLEAR_MASK ((uint16_t)(USART_CR3_RTSE | USART_CR3_CTSE))
+
+/*!< USART Interrupts mask */
+#define IT_MASK ((uint16_t)0x001F)
+
+/* Private macro -------------------------------------------------------------*/
+/* Private variables ---------------------------------------------------------*/
+/* Private function prototypes -----------------------------------------------*/
+/* Private functions ---------------------------------------------------------*/
+
+/** @defgroup USART_Private_Functions
+ * @{
+ */
+
+/** @defgroup USART_Group1 Initialization and Configuration functions
+ * @brief Initialization and Configuration functions
+ *
+@verbatim
+ ===============================================================================
+ Initialization and Configuration functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to initialize the USART
+ in asynchronous and in synchronous modes.
+ - For the asynchronous mode only these parameters can be configured:
+ - Baud Rate
+ - Word Length
+ - Stop Bit
+ - Parity: If the parity is enabled, then the MSB bit of the data written
+ in the data register is transmitted but is changed by the parity bit.
+ Depending on the frame length defined by the M bit (8-bits or 9-bits),
+ the possible USART frame formats are as listed in the following table:
+ +-------------------------------------------------------------+
+ | M bit | PCE bit | USART frame |
+ |---------------------|---------------------------------------|
+ | 0 | 0 | | SB | 8 bit data | STB | |
+ |---------|-----------|---------------------------------------|
+ | 0 | 1 | | SB | 7 bit data | PB | STB | |
+ |---------|-----------|---------------------------------------|
+ | 1 | 0 | | SB | 9 bit data | STB | |
+ |---------|-----------|---------------------------------------|
+ | 1 | 1 | | SB | 8 bit data | PB | STB | |
+ +-------------------------------------------------------------+
+ - Hardware flow control
+ - Receiver/transmitter modes
+
+ The USART_Init() function follows the USART asynchronous configuration procedure
+ (details for the procedure are available in reference manual (RM0090)).
+
+ - For the synchronous mode in addition to the asynchronous mode parameters these
+ parameters should be also configured:
+ - USART Clock Enabled
+ - USART polarity
+ - USART phase
+ - USART LastBit
+
+ These parameters can be configured using the USART_ClockInit() function.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Deinitializes the USARTx peripheral registers to their default reset values.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @retval None
+ */
+void USART_DeInit(USART_TypeDef* USARTx)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+
+ if (USARTx == USART1)
+ {
+ RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART1, ENABLE);
+ RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART1, DISABLE);
+ }
+ else if (USARTx == USART2)
+ {
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART2, ENABLE);
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART2, DISABLE);
+ }
+ else if (USARTx == USART3)
+ {
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART3, ENABLE);
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART3, DISABLE);
+ }
+ else if (USARTx == UART4)
+ {
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_UART4, ENABLE);
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_UART4, DISABLE);
+ }
+ else if (USARTx == UART5)
+ {
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_UART5, ENABLE);
+ RCC_APB1PeriphResetCmd(RCC_APB1Periph_UART5, DISABLE);
+ }
+ else
+ {
+ if (USARTx == USART6)
+ {
+ RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART6, ENABLE);
+ RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART6, DISABLE);
+ }
+ }
+}
+
+/**
+ * @brief Initializes the USARTx peripheral according to the specified
+ * parameters in the USART_InitStruct .
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_InitStruct: pointer to a USART_InitTypeDef structure that contains
+ * the configuration information for the specified USART peripheral.
+ * @retval None
+ */
+void USART_Init(USART_TypeDef* USARTx, USART_InitTypeDef* USART_InitStruct)
+{
+ uint32_t tmpreg = 0x00, apbclock = 0x00;
+ uint32_t integerdivider = 0x00;
+ uint32_t fractionaldivider = 0x00;
+ RCC_ClocksTypeDef RCC_ClocksStatus;
+
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_BAUDRATE(USART_InitStruct->USART_BaudRate));
+ assert_param(IS_USART_WORD_LENGTH(USART_InitStruct->USART_WordLength));
+ assert_param(IS_USART_STOPBITS(USART_InitStruct->USART_StopBits));
+ assert_param(IS_USART_PARITY(USART_InitStruct->USART_Parity));
+ assert_param(IS_USART_MODE(USART_InitStruct->USART_Mode));
+ assert_param(IS_USART_HARDWARE_FLOW_CONTROL(USART_InitStruct->USART_HardwareFlowControl));
+
+ /* The hardware flow control is available only for USART1, USART2, USART3 and USART6 */
+ if (USART_InitStruct->USART_HardwareFlowControl != USART_HardwareFlowControl_None)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+/*---------------------------- USART CR2 Configuration -----------------------*/
+ tmpreg = USARTx->CR2;
+
+ /* Clear STOP[13:12] bits */
+ tmpreg &= (uint32_t)~((uint32_t)USART_CR2_STOP);
+
+ /* Configure the USART Stop Bits, Clock, CPOL, CPHA and LastBit :
+ Set STOP[13:12] bits according to USART_StopBits value */
+ tmpreg |= (uint32_t)USART_InitStruct->USART_StopBits;
+
+ /* Write to USART CR2 */
+ USARTx->CR2 = (uint16_t)tmpreg;
+
+/*---------------------------- USART CR1 Configuration -----------------------*/
+ tmpreg = USARTx->CR1;
+
+ /* Clear M, PCE, PS, TE and RE bits */
+ tmpreg &= (uint32_t)~((uint32_t)CR1_CLEAR_MASK);
+
+ /* Configure the USART Word Length, Parity and mode:
+ Set the M bits according to USART_WordLength value
+ Set PCE and PS bits according to USART_Parity value
+ Set TE and RE bits according to USART_Mode value */
+ tmpreg |= (uint32_t)USART_InitStruct->USART_WordLength | USART_InitStruct->USART_Parity |
+ USART_InitStruct->USART_Mode;
+
+ /* Write to USART CR1 */
+ USARTx->CR1 = (uint16_t)tmpreg;
+
+/*---------------------------- USART CR3 Configuration -----------------------*/
+ tmpreg = USARTx->CR3;
+
+ /* Clear CTSE and RTSE bits */
+ tmpreg &= (uint32_t)~((uint32_t)CR3_CLEAR_MASK);
+
+ /* Configure the USART HFC :
+ Set CTSE and RTSE bits according to USART_HardwareFlowControl value */
+ tmpreg |= USART_InitStruct->USART_HardwareFlowControl;
+
+ /* Write to USART CR3 */
+ USARTx->CR3 = (uint16_t)tmpreg;
+
+/*---------------------------- USART BRR Configuration -----------------------*/
+ /* Configure the USART Baud Rate */
+ RCC_GetClocksFreq(&RCC_ClocksStatus);
+
+ if ((USARTx == USART1) || (USARTx == USART6))
+ {
+ apbclock = RCC_ClocksStatus.PCLK2_Frequency;
+ }
+ else
+ {
+ apbclock = RCC_ClocksStatus.PCLK1_Frequency;
+ }
+
+ /* Determine the integer part */
+ if ((USARTx->CR1 & USART_CR1_OVER8) != 0)
+ {
+ /* Integer part computing in case Oversampling mode is 8 Samples */
+ integerdivider = ((25 * apbclock) / (2 * (USART_InitStruct->USART_BaudRate)));
+ }
+ else /* if ((USARTx->CR1 & USART_CR1_OVER8) == 0) */
+ {
+ /* Integer part computing in case Oversampling mode is 16 Samples */
+ integerdivider = ((25 * apbclock) / (4 * (USART_InitStruct->USART_BaudRate)));
+ }
+ tmpreg = (integerdivider / 100) << 4;
+
+ /* Determine the fractional part */
+ fractionaldivider = integerdivider - (100 * (tmpreg >> 4));
+
+ /* Implement the fractional part in the register */
+ if ((USARTx->CR1 & USART_CR1_OVER8) != 0)
+ {
+ tmpreg |= ((((fractionaldivider * 8) + 50) / 100)) & ((uint8_t)0x07);
+ }
+ else /* if ((USARTx->CR1 & USART_CR1_OVER8) == 0) */
+ {
+ tmpreg |= ((((fractionaldivider * 16) + 50) / 100)) & ((uint8_t)0x0F);
+ }
+
+ /* Write to USART BRR register */
+ USARTx->BRR = (uint16_t)tmpreg;
+}
+
+/**
+ * @brief Fills each USART_InitStruct member with its default value.
+ * @param USART_InitStruct: pointer to a USART_InitTypeDef structure which will
+ * be initialized.
+ * @retval None
+ */
+void USART_StructInit(USART_InitTypeDef* USART_InitStruct)
+{
+ /* USART_InitStruct members default value */
+ USART_InitStruct->USART_BaudRate = 9600;
+ USART_InitStruct->USART_WordLength = USART_WordLength_8b;
+ USART_InitStruct->USART_StopBits = USART_StopBits_1;
+ USART_InitStruct->USART_Parity = USART_Parity_No ;
+ USART_InitStruct->USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
+ USART_InitStruct->USART_HardwareFlowControl = USART_HardwareFlowControl_None;
+}
+
+/**
+ * @brief Initializes the USARTx peripheral Clock according to the
+ * specified parameters in the USART_ClockInitStruct .
+ * @param USARTx: where x can be 1, 2, 3 or 6 to select the USART peripheral.
+ * @param USART_ClockInitStruct: pointer to a USART_ClockInitTypeDef structure that
+ * contains the configuration information for the specified USART peripheral.
+ * @note The Smart Card and Synchronous modes are not available for UART4 and UART5.
+ * @retval None
+ */
+void USART_ClockInit(USART_TypeDef* USARTx, USART_ClockInitTypeDef* USART_ClockInitStruct)
+{
+ uint32_t tmpreg = 0x00;
+ /* Check the parameters */
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ assert_param(IS_USART_CLOCK(USART_ClockInitStruct->USART_Clock));
+ assert_param(IS_USART_CPOL(USART_ClockInitStruct->USART_CPOL));
+ assert_param(IS_USART_CPHA(USART_ClockInitStruct->USART_CPHA));
+ assert_param(IS_USART_LASTBIT(USART_ClockInitStruct->USART_LastBit));
+
+/*---------------------------- USART CR2 Configuration -----------------------*/
+ tmpreg = USARTx->CR2;
+ /* Clear CLKEN, CPOL, CPHA and LBCL bits */
+ tmpreg &= (uint32_t)~((uint32_t)CR2_CLOCK_CLEAR_MASK);
+ /* Configure the USART Clock, CPOL, CPHA and LastBit ------------*/
+ /* Set CLKEN bit according to USART_Clock value */
+ /* Set CPOL bit according to USART_CPOL value */
+ /* Set CPHA bit according to USART_CPHA value */
+ /* Set LBCL bit according to USART_LastBit value */
+ tmpreg |= (uint32_t)USART_ClockInitStruct->USART_Clock | USART_ClockInitStruct->USART_CPOL |
+ USART_ClockInitStruct->USART_CPHA | USART_ClockInitStruct->USART_LastBit;
+ /* Write to USART CR2 */
+ USARTx->CR2 = (uint16_t)tmpreg;
+}
+
+/**
+ * @brief Fills each USART_ClockInitStruct member with its default value.
+ * @param USART_ClockInitStruct: pointer to a USART_ClockInitTypeDef structure
+ * which will be initialized.
+ * @retval None
+ */
+void USART_ClockStructInit(USART_ClockInitTypeDef* USART_ClockInitStruct)
+{
+ /* USART_ClockInitStruct members default value */
+ USART_ClockInitStruct->USART_Clock = USART_Clock_Disable;
+ USART_ClockInitStruct->USART_CPOL = USART_CPOL_Low;
+ USART_ClockInitStruct->USART_CPHA = USART_CPHA_1Edge;
+ USART_ClockInitStruct->USART_LastBit = USART_LastBit_Disable;
+}
+
+/**
+ * @brief Enables or disables the specified USART peripheral.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USARTx peripheral.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_Cmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the selected USART by setting the UE bit in the CR1 register */
+ USARTx->CR1 |= USART_CR1_UE;
+ }
+ else
+ {
+ /* Disable the selected USART by clearing the UE bit in the CR1 register */
+ USARTx->CR1 &= (uint16_t)~((uint16_t)USART_CR1_UE);
+ }
+}
+
+/**
+ * @brief Sets the system clock prescaler.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_Prescaler: specifies the prescaler clock.
+ * @note The function is used for IrDA mode with UART4 and UART5.
+ * @retval None
+ */
+void USART_SetPrescaler(USART_TypeDef* USARTx, uint8_t USART_Prescaler)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+
+ /* Clear the USART prescaler */
+ USARTx->GTPR &= USART_GTPR_GT;
+ /* Set the USART prescaler */
+ USARTx->GTPR |= USART_Prescaler;
+}
+
+/**
+ * @brief Enables or disables the USART's 8x oversampling mode.
+ * @note This function has to be called before calling USART_Init() function
+ * in order to have correct baudrate Divider value.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USART 8x oversampling mode.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_OverSampling8Cmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the 8x Oversampling mode by setting the OVER8 bit in the CR1 register */
+ USARTx->CR1 |= USART_CR1_OVER8;
+ }
+ else
+ {
+ /* Disable the 8x Oversampling mode by clearing the OVER8 bit in the CR1 register */
+ USARTx->CR1 &= (uint16_t)~((uint16_t)USART_CR1_OVER8);
+ }
+}
+
+/**
+ * @brief Enables or disables the USART's one bit sampling method.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USART one bit sampling method.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_OneBitMethodCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the one bit method by setting the ONEBITE bit in the CR3 register */
+ USARTx->CR3 |= USART_CR3_ONEBIT;
+ }
+ else
+ {
+ /* Disable the one bit method by clearing the ONEBITE bit in the CR3 register */
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_ONEBIT);
+ }
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group2 Data transfers functions
+ * @brief Data transfers functions
+ *
+@verbatim
+ ===============================================================================
+ Data transfers functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART data
+ transfers.
+
+ During an USART reception, data shifts in least significant bit first through
+ the RX pin. In this mode, the USART_DR register consists of a buffer (RDR)
+ between the internal bus and the received shift register.
+
+ When a transmission is taking place, a write instruction to the USART_DR register
+ stores the data in the TDR register and which is copied in the shift register
+ at the end of the current transmission.
+
+ The read access of the USART_DR register can be done using the USART_ReceiveData()
+ function and returns the RDR buffered value. Whereas a write access to the USART_DR
+ can be done using USART_SendData() function and stores the written data into
+ TDR buffer.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Transmits single data through the USARTx peripheral.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param Data: the data to transmit.
+ * @retval None
+ */
+void USART_SendData(USART_TypeDef* USARTx, uint16_t Data)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_DATA(Data));
+
+ /* Transmit Data */
+ USARTx->DR = (Data & (uint16_t)0x01FF);
+}
+
+/**
+ * @brief Returns the most recent received data by the USARTx peripheral.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @retval The received data.
+ */
+uint16_t USART_ReceiveData(USART_TypeDef* USARTx)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+
+ /* Receive Data */
+ return (uint16_t)(USARTx->DR & (uint16_t)0x01FF);
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group3 MultiProcessor Communication functions
+ * @brief Multi-Processor Communication functions
+ *
+@verbatim
+ ===============================================================================
+ Multi-Processor Communication functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART
+ multiprocessor communication.
+
+ For instance one of the USARTs can be the master, its TX output is connected to
+ the RX input of the other USART. The others are slaves, their respective TX outputs
+ are logically ANDed together and connected to the RX input of the master.
+
+ USART multiprocessor communication is possible through the following procedure:
+ 1. Program the Baud rate, Word length = 9 bits, Stop bits, Parity, Mode transmitter
+ or Mode receiver and hardware flow control values using the USART_Init()
+ function.
+ 2. Configures the USART address using the USART_SetAddress() function.
+ 3. Configures the wake up method (USART_WakeUp_IdleLine or USART_WakeUp_AddressMark)
+ using USART_WakeUpConfig() function only for the slaves.
+ 4. Enable the USART using the USART_Cmd() function.
+ 5. Enter the USART slaves in mute mode using USART_ReceiverWakeUpCmd() function.
+
+ The USART Slave exit from mute mode when receive the wake up condition.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Sets the address of the USART node.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_Address: Indicates the address of the USART node.
+ * @retval None
+ */
+void USART_SetAddress(USART_TypeDef* USARTx, uint8_t USART_Address)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_ADDRESS(USART_Address));
+
+ /* Clear the USART address */
+ USARTx->CR2 &= (uint16_t)~((uint16_t)USART_CR2_ADD);
+ /* Set the USART address node */
+ USARTx->CR2 |= USART_Address;
+}
+
+/**
+ * @brief Determines if the USART is in mute mode or not.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USART mute mode.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_ReceiverWakeUpCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the USART mute mode by setting the RWU bit in the CR1 register */
+ USARTx->CR1 |= USART_CR1_RWU;
+ }
+ else
+ {
+ /* Disable the USART mute mode by clearing the RWU bit in the CR1 register */
+ USARTx->CR1 &= (uint16_t)~((uint16_t)USART_CR1_RWU);
+ }
+}
+/**
+ * @brief Selects the USART WakeUp method.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_WakeUp: specifies the USART wakeup method.
+ * This parameter can be one of the following values:
+ * @arg USART_WakeUp_IdleLine: WakeUp by an idle line detection
+ * @arg USART_WakeUp_AddressMark: WakeUp by an address mark
+ * @retval None
+ */
+void USART_WakeUpConfig(USART_TypeDef* USARTx, uint16_t USART_WakeUp)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_WAKEUP(USART_WakeUp));
+
+ USARTx->CR1 &= (uint16_t)~((uint16_t)USART_CR1_WAKE);
+ USARTx->CR1 |= USART_WakeUp;
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group4 LIN mode functions
+ * @brief LIN mode functions
+ *
+@verbatim
+ ===============================================================================
+ LIN mode functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART LIN
+ Mode communication.
+
+ In LIN mode, 8-bit data format with 1 stop bit is required in accordance with
+ the LIN standard.
+
+ Only this LIN Feature is supported by the USART IP:
+ - LIN Master Synchronous Break send capability and LIN slave break detection
+ capability : 13-bit break generation and 10/11 bit break detection
+
+
+ USART LIN Master transmitter communication is possible through the following procedure:
+ 1. Program the Baud rate, Word length = 8bits, Stop bits = 1bit, Parity,
+ Mode transmitter or Mode receiver and hardware flow control values using
+ the USART_Init() function.
+ 2. Enable the USART using the USART_Cmd() function.
+ 3. Enable the LIN mode using the USART_LINCmd() function.
+ 4. Send the break character using USART_SendBreak() function.
+
+ USART LIN Master receiver communication is possible through the following procedure:
+ 1. Program the Baud rate, Word length = 8bits, Stop bits = 1bit, Parity,
+ Mode transmitter or Mode receiver and hardware flow control values using
+ the USART_Init() function.
+ 2. Enable the USART using the USART_Cmd() function.
+ 3. Configures the break detection length using the USART_LINBreakDetectLengthConfig()
+ function.
+ 4. Enable the LIN mode using the USART_LINCmd() function.
+
+
+@note In LIN mode, the following bits must be kept cleared:
+ - CLKEN in the USART_CR2 register,
+ - STOP[1:0], SCEN, HDSEL and IREN in the USART_CR3 register.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Sets the USART LIN Break detection length.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_LINBreakDetectLength: specifies the LIN break detection length.
+ * This parameter can be one of the following values:
+ * @arg USART_LINBreakDetectLength_10b: 10-bit break detection
+ * @arg USART_LINBreakDetectLength_11b: 11-bit break detection
+ * @retval None
+ */
+void USART_LINBreakDetectLengthConfig(USART_TypeDef* USARTx, uint16_t USART_LINBreakDetectLength)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_LIN_BREAK_DETECT_LENGTH(USART_LINBreakDetectLength));
+
+ USARTx->CR2 &= (uint16_t)~((uint16_t)USART_CR2_LBDL);
+ USARTx->CR2 |= USART_LINBreakDetectLength;
+}
+
+/**
+ * @brief Enables or disables the USART's LIN mode.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USART LIN mode.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_LINCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the LIN mode by setting the LINEN bit in the CR2 register */
+ USARTx->CR2 |= USART_CR2_LINEN;
+ }
+ else
+ {
+ /* Disable the LIN mode by clearing the LINEN bit in the CR2 register */
+ USARTx->CR2 &= (uint16_t)~((uint16_t)USART_CR2_LINEN);
+ }
+}
+
+/**
+ * @brief Transmits break characters.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @retval None
+ */
+void USART_SendBreak(USART_TypeDef* USARTx)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+
+ /* Send break characters */
+ USARTx->CR1 |= USART_CR1_SBK;
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group5 Halfduplex mode function
+ * @brief Half-duplex mode function
+ *
+@verbatim
+ ===============================================================================
+ Half-duplex mode function
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART
+ Half-duplex communication.
+
+ The USART can be configured to follow a single-wire half-duplex protocol where
+ the TX and RX lines are internally connected.
+
+ USART Half duplex communication is possible through the following procedure:
+ 1. Program the Baud rate, Word length, Stop bits, Parity, Mode transmitter
+ or Mode receiver and hardware flow control values using the USART_Init()
+ function.
+ 2. Configures the USART address using the USART_SetAddress() function.
+ 3. Enable the USART using the USART_Cmd() function.
+ 4. Enable the half duplex mode using USART_HalfDuplexCmd() function.
+
+
+@note The RX pin is no longer used
+@note In Half-duplex mode the following bits must be kept cleared:
+ - LINEN and CLKEN bits in the USART_CR2 register.
+ - SCEN and IREN bits in the USART_CR3 register.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Enables or disables the USART's Half Duplex communication.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the USART Communication.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_HalfDuplexCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the Half-Duplex mode by setting the HDSEL bit in the CR3 register */
+ USARTx->CR3 |= USART_CR3_HDSEL;
+ }
+ else
+ {
+ /* Disable the Half-Duplex mode by clearing the HDSEL bit in the CR3 register */
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_HDSEL);
+ }
+}
+
+/**
+ * @}
+ */
+
+
+/** @defgroup USART_Group6 Smartcard mode functions
+ * @brief Smartcard mode functions
+ *
+@verbatim
+ ===============================================================================
+ Smartcard mode functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART
+ Smartcard communication.
+
+ The Smartcard interface is designed to support asynchronous protocol Smartcards as
+ defined in the ISO 7816-3 standard.
+
+ The USART can provide a clock to the smartcard through the SCLK output.
+ In smartcard mode, SCLK is not associated to the communication but is simply derived
+ from the internal peripheral input clock through a 5-bit prescaler.
+
+ Smartcard communication is possible through the following procedure:
+ 1. Configures the Smartcard Prescaler using the USART_SetPrescaler() function.
+ 2. Configures the Smartcard Guard Time using the USART_SetGuardTime() function.
+ 3. Program the USART clock using the USART_ClockInit() function as following:
+ - USART Clock enabled
+ - USART CPOL Low
+ - USART CPHA on first edge
+ - USART Last Bit Clock Enabled
+ 4. Program the Smartcard interface using the USART_Init() function as following:
+ - Word Length = 9 Bits
+ - 1.5 Stop Bit
+ - Even parity
+ - BaudRate = 12096 baud
+ - Hardware flow control disabled (RTS and CTS signals)
+ - Tx and Rx enabled
+ 5. Optionally you can enable the parity error interrupt using the USART_ITConfig()
+ function
+ 6. Enable the USART using the USART_Cmd() function.
+ 7. Enable the Smartcard NACK using the USART_SmartCardNACKCmd() function.
+ 8. Enable the Smartcard interface using the USART_SmartCardCmd() function.
+
+ Please refer to the ISO 7816-3 specification for more details.
+
+
+@note It is also possible to choose 0.5 stop bit for receiving but it is recommended
+ to use 1.5 stop bits for both transmitting and receiving to avoid switching
+ between the two configurations.
+@note In smartcard mode, the following bits must be kept cleared:
+ - LINEN bit in the USART_CR2 register.
+ - HDSEL and IREN bits in the USART_CR3 register.
+@note Smartcard mode is available on USART peripherals only (not available on UART4
+ and UART5 peripherals).
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Sets the specified USART guard time.
+ * @param USARTx: where x can be 1, 2, 3 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_GuardTime: specifies the guard time.
+ * @retval None
+ */
+void USART_SetGuardTime(USART_TypeDef* USARTx, uint8_t USART_GuardTime)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+
+ /* Clear the USART Guard time */
+ USARTx->GTPR &= USART_GTPR_PSC;
+ /* Set the USART guard time */
+ USARTx->GTPR |= (uint16_t)((uint16_t)USART_GuardTime << 0x08);
+}
+
+/**
+ * @brief Enables or disables the USART's Smart Card mode.
+ * @param USARTx: where x can be 1, 2, 3 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the Smart Card mode.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_SmartCardCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+ if (NewState != DISABLE)
+ {
+ /* Enable the SC mode by setting the SCEN bit in the CR3 register */
+ USARTx->CR3 |= USART_CR3_SCEN;
+ }
+ else
+ {
+ /* Disable the SC mode by clearing the SCEN bit in the CR3 register */
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_SCEN);
+ }
+}
+
+/**
+ * @brief Enables or disables NACK transmission.
+ * @param USARTx: where x can be 1, 2, 3 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the NACK transmission.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_SmartCardNACKCmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+ if (NewState != DISABLE)
+ {
+ /* Enable the NACK transmission by setting the NACK bit in the CR3 register */
+ USARTx->CR3 |= USART_CR3_NACK;
+ }
+ else
+ {
+ /* Disable the NACK transmission by clearing the NACK bit in the CR3 register */
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_NACK);
+ }
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group7 IrDA mode functions
+ * @brief IrDA mode functions
+ *
+@verbatim
+ ===============================================================================
+ IrDA mode functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to manage the USART
+ IrDA communication.
+
+ IrDA is a half duplex communication protocol. If the Transmitter is busy, any data
+ on the IrDA receive line will be ignored by the IrDA decoder and if the Receiver
+ is busy, data on the TX from the USART to IrDA will not be encoded by IrDA.
+ While receiving data, transmission should be avoided as the data to be transmitted
+ could be corrupted.
+
+ IrDA communication is possible through the following procedure:
+ 1. Program the Baud rate, Word length = 8 bits, Stop bits, Parity, Transmitter/Receiver
+ modes and hardware flow control values using the USART_Init() function.
+ 2. Enable the USART using the USART_Cmd() function.
+ 3. Configures the IrDA pulse width by configuring the prescaler using
+ the USART_SetPrescaler() function.
+ 4. Configures the IrDA USART_IrDAMode_LowPower or USART_IrDAMode_Normal mode
+ using the USART_IrDAConfig() function.
+ 5. Enable the IrDA using the USART_IrDACmd() function.
+
+@note A pulse of width less than two and greater than one PSC period(s) may or may
+ not be rejected.
+@note The receiver set up time should be managed by software. The IrDA physical layer
+ specification specifies a minimum of 10 ms delay between transmission and
+ reception (IrDA is a half duplex protocol).
+@note In IrDA mode, the following bits must be kept cleared:
+ - LINEN, STOP and CLKEN bits in the USART_CR2 register.
+ - SCEN and HDSEL bits in the USART_CR3 register.
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Configures the USART's IrDA interface.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_IrDAMode: specifies the IrDA mode.
+ * This parameter can be one of the following values:
+ * @arg USART_IrDAMode_LowPower
+ * @arg USART_IrDAMode_Normal
+ * @retval None
+ */
+void USART_IrDAConfig(USART_TypeDef* USARTx, uint16_t USART_IrDAMode)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_IRDA_MODE(USART_IrDAMode));
+
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_IRLP);
+ USARTx->CR3 |= USART_IrDAMode;
+}
+
+/**
+ * @brief Enables or disables the USART's IrDA interface.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param NewState: new state of the IrDA mode.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_IrDACmd(USART_TypeDef* USARTx, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the IrDA mode by setting the IREN bit in the CR3 register */
+ USARTx->CR3 |= USART_CR3_IREN;
+ }
+ else
+ {
+ /* Disable the IrDA mode by clearing the IREN bit in the CR3 register */
+ USARTx->CR3 &= (uint16_t)~((uint16_t)USART_CR3_IREN);
+ }
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group8 DMA transfers management functions
+ * @brief DMA transfers management functions
+ *
+@verbatim
+ ===============================================================================
+ DMA transfers management functions
+ ===============================================================================
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Enables or disables the USART's DMA interface.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_DMAReq: specifies the DMA request.
+ * This parameter can be any combination of the following values:
+ * @arg USART_DMAReq_Tx: USART DMA transmit request
+ * @arg USART_DMAReq_Rx: USART DMA receive request
+ * @param NewState: new state of the DMA Request sources.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_DMACmd(USART_TypeDef* USARTx, uint16_t USART_DMAReq, FunctionalState NewState)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_DMAREQ(USART_DMAReq));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ if (NewState != DISABLE)
+ {
+ /* Enable the DMA transfer for selected requests by setting the DMAT and/or
+ DMAR bits in the USART CR3 register */
+ USARTx->CR3 |= USART_DMAReq;
+ }
+ else
+ {
+ /* Disable the DMA transfer for selected requests by clearing the DMAT and/or
+ DMAR bits in the USART CR3 register */
+ USARTx->CR3 &= (uint16_t)~USART_DMAReq;
+ }
+}
+
+/**
+ * @}
+ */
+
+/** @defgroup USART_Group9 Interrupts and flags management functions
+ * @brief Interrupts and flags management functions
+ *
+@verbatim
+ ===============================================================================
+ Interrupts and flags management functions
+ ===============================================================================
+
+ This subsection provides a set of functions allowing to configure the USART
+ Interrupts sources, DMA channels requests and check or clear the flags or
+ pending bits status.
+ The user should identify which mode will be used in his application to manage
+ the communication: Polling mode, Interrupt mode or DMA mode.
+
+ Polling Mode
+ =============
+ In Polling Mode, the SPI communication can be managed by 10 flags:
+ 1. USART_FLAG_TXE : to indicate the status of the transmit buffer register
+ 2. USART_FLAG_RXNE : to indicate the status of the receive buffer register
+ 3. USART_FLAG_TC : to indicate the status of the transmit operation
+ 4. USART_FLAG_IDLE : to indicate the status of the Idle Line
+ 5. USART_FLAG_CTS : to indicate the status of the nCTS input
+ 6. USART_FLAG_LBD : to indicate the status of the LIN break detection
+ 7. USART_FLAG_NE : to indicate if a noise error occur
+ 8. USART_FLAG_FE : to indicate if a frame error occur
+ 9. USART_FLAG_PE : to indicate if a parity error occur
+ 10. USART_FLAG_ORE : to indicate if an Overrun error occur
+
+ In this Mode it is advised to use the following functions:
+ - FlagStatus USART_GetFlagStatus(USART_TypeDef* USARTx, uint16_t USART_FLAG);
+ - void USART_ClearFlag(USART_TypeDef* USARTx, uint16_t USART_FLAG);
+
+ Interrupt Mode
+ ===============
+ In Interrupt Mode, the USART communication can be managed by 8 interrupt sources
+ and 10 pending bits:
+
+ Pending Bits:
+ -------------
+ 1. USART_IT_TXE : to indicate the status of the transmit buffer register
+ 2. USART_IT_RXNE : to indicate the status of the receive buffer register
+ 3. USART_IT_TC : to indicate the status of the transmit operation
+ 4. USART_IT_IDLE : to indicate the status of the Idle Line
+ 5. USART_IT_CTS : to indicate the status of the nCTS input
+ 6. USART_IT_LBD : to indicate the status of the LIN break detection
+ 7. USART_IT_NE : to indicate if a noise error occur
+ 8. USART_IT_FE : to indicate if a frame error occur
+ 9. USART_IT_PE : to indicate if a parity error occur
+ 10. USART_IT_ORE : to indicate if an Overrun error occur
+
+ Interrupt Source:
+ -----------------
+ 1. USART_IT_TXE : specifies the interrupt source for the Tx buffer empty
+ interrupt.
+ 2. USART_IT_RXNE : specifies the interrupt source for the Rx buffer not
+ empty interrupt.
+ 3. USART_IT_TC : specifies the interrupt source for the Transmit complete
+ interrupt.
+ 4. USART_IT_IDLE : specifies the interrupt source for the Idle Line interrupt.
+ 5. USART_IT_CTS : specifies the interrupt source for the CTS interrupt.
+ 6. USART_IT_LBD : specifies the interrupt source for the LIN break detection
+ interrupt.
+ 7. USART_IT_PE : specifies the interrupt source for the parity error interrupt.
+ 8. USART_IT_ERR : specifies the interrupt source for the errors interrupt.
+
+@note Some parameters are coded in order to use them as interrupt source or as pending bits.
+
+ In this Mode it is advised to use the following functions:
+ - void USART_ITConfig(USART_TypeDef* USARTx, uint16_t USART_IT, FunctionalState NewState);
+ - ITStatus USART_GetITStatus(USART_TypeDef* USARTx, uint16_t USART_IT);
+ - void USART_ClearITPendingBit(USART_TypeDef* USARTx, uint16_t USART_IT);
+
+ DMA Mode
+ ========
+ In DMA Mode, the USART communication can be managed by 2 DMA Channel requests:
+ 1. USART_DMAReq_Tx: specifies the Tx buffer DMA transfer request
+ 2. USART_DMAReq_Rx: specifies the Rx buffer DMA transfer request
+
+ In this Mode it is advised to use the following function:
+ - void USART_DMACmd(USART_TypeDef* USARTx, uint16_t USART_DMAReq, FunctionalState NewState);
+
+@endverbatim
+ * @{
+ */
+
+/**
+ * @brief Enables or disables the specified USART interrupts.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_IT: specifies the USART interrupt sources to be enabled or disabled.
+ * This parameter can be one of the following values:
+ * @arg USART_IT_CTS: CTS change interrupt
+ * @arg USART_IT_LBD: LIN Break detection interrupt
+ * @arg USART_IT_TXE: Transmit Data Register empty interrupt
+ * @arg USART_IT_TC: Transmission complete interrupt
+ * @arg USART_IT_RXNE: Receive Data register not empty interrupt
+ * @arg USART_IT_IDLE: Idle line detection interrupt
+ * @arg USART_IT_PE: Parity Error interrupt
+ * @arg USART_IT_ERR: Error interrupt(Frame error, noise error, overrun error)
+ * @param NewState: new state of the specified USARTx interrupts.
+ * This parameter can be: ENABLE or DISABLE.
+ * @retval None
+ */
+void USART_ITConfig(USART_TypeDef* USARTx, uint16_t USART_IT, FunctionalState NewState)
+{
+ uint32_t usartreg = 0x00, itpos = 0x00, itmask = 0x00;
+ uint32_t usartxbase = 0x00;
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_CONFIG_IT(USART_IT));
+ assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+ /* The CTS interrupt is not available for UART4 and UART5 */
+ if (USART_IT == USART_IT_CTS)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+ usartxbase = (uint32_t)USARTx;
+
+ /* Get the USART register index */
+ usartreg = (((uint8_t)USART_IT) >> 0x05);
+
+ /* Get the interrupt position */
+ itpos = USART_IT & IT_MASK;
+ itmask = (((uint32_t)0x01) << itpos);
+
+ if (usartreg == 0x01) /* The IT is in CR1 register */
+ {
+ usartxbase += 0x0C;
+ }
+ else if (usartreg == 0x02) /* The IT is in CR2 register */
+ {
+ usartxbase += 0x10;
+ }
+ else /* The IT is in CR3 register */
+ {
+ usartxbase += 0x14;
+ }
+ if (NewState != DISABLE)
+ {
+ *(__IO uint32_t*)usartxbase |= itmask;
+ }
+ else
+ {
+ *(__IO uint32_t*)usartxbase &= ~itmask;
+ }
+}
+
+/**
+ * @brief Checks whether the specified USART flag is set or not.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_FLAG: specifies the flag to check.
+ * This parameter can be one of the following values:
+ * @arg USART_FLAG_CTS: CTS Change flag (not available for UART4 and UART5)
+ * @arg USART_FLAG_LBD: LIN Break detection flag
+ * @arg USART_FLAG_TXE: Transmit data register empty flag
+ * @arg USART_FLAG_TC: Transmission Complete flag
+ * @arg USART_FLAG_RXNE: Receive data register not empty flag
+ * @arg USART_FLAG_IDLE: Idle Line detection flag
+ * @arg USART_FLAG_ORE: OverRun Error flag
+ * @arg USART_FLAG_NE: Noise Error flag
+ * @arg USART_FLAG_FE: Framing Error flag
+ * @arg USART_FLAG_PE: Parity Error flag
+ * @retval The new state of USART_FLAG (SET or RESET).
+ */
+FlagStatus USART_GetFlagStatus(USART_TypeDef* USARTx, uint16_t USART_FLAG)
+{
+ FlagStatus bitstatus = RESET;
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_FLAG(USART_FLAG));
+
+ /* The CTS flag is not available for UART4 and UART5 */
+ if (USART_FLAG == USART_FLAG_CTS)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+ if ((USARTx->SR & USART_FLAG) != (uint16_t)RESET)
+ {
+ bitstatus = SET;
+ }
+ else
+ {
+ bitstatus = RESET;
+ }
+ return bitstatus;
+}
+
+/**
+ * @brief Clears the USARTx's pending flags.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_FLAG: specifies the flag to clear.
+ * This parameter can be any combination of the following values:
+ * @arg USART_FLAG_CTS: CTS Change flag (not available for UART4 and UART5).
+ * @arg USART_FLAG_LBD: LIN Break detection flag.
+ * @arg USART_FLAG_TC: Transmission Complete flag.
+ * @arg USART_FLAG_RXNE: Receive data register not empty flag.
+ *
+ * @note PE (Parity error), FE (Framing error), NE (Noise error), ORE (OverRun
+ * error) and IDLE (Idle line detected) flags are cleared by software
+ * sequence: a read operation to USART_SR register (USART_GetFlagStatus())
+ * followed by a read operation to USART_DR register (USART_ReceiveData()).
+ * @note RXNE flag can be also cleared by a read to the USART_DR register
+ * (USART_ReceiveData()).
+ * @note TC flag can be also cleared by software sequence: a read operation to
+ * USART_SR register (USART_GetFlagStatus()) followed by a write operation
+ * to USART_DR register (USART_SendData()).
+ * @note TXE flag is cleared only by a write to the USART_DR register
+ * (USART_SendData()).
+ *
+ * @retval None
+ */
+void USART_ClearFlag(USART_TypeDef* USARTx, uint16_t USART_FLAG)
+{
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_CLEAR_FLAG(USART_FLAG));
+
+ /* The CTS flag is not available for UART4 and UART5 */
+ if ((USART_FLAG & USART_FLAG_CTS) == USART_FLAG_CTS)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+ USARTx->SR = (uint16_t)~USART_FLAG;
+}
+
+/**
+ * @brief Checks whether the specified USART interrupt has occurred or not.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_IT: specifies the USART interrupt source to check.
+ * This parameter can be one of the following values:
+ * @arg USART_IT_CTS: CTS change interrupt (not available for UART4 and UART5)
+ * @arg USART_IT_LBD: LIN Break detection interrupt
+ * @arg USART_IT_TXE: Transmit Data Register empty interrupt
+ * @arg USART_IT_TC: Transmission complete interrupt
+ * @arg USART_IT_RXNE: Receive Data register not empty interrupt
+ * @arg USART_IT_IDLE: Idle line detection interrupt
+ * @arg USART_IT_ORE: OverRun Error interrupt
+ * @arg USART_IT_NE: Noise Error interrupt
+ * @arg USART_IT_FE: Framing Error interrupt
+ * @arg USART_IT_PE: Parity Error interrupt
+ * @retval The new state of USART_IT (SET or RESET).
+ */
+ITStatus USART_GetITStatus(USART_TypeDef* USARTx, uint16_t USART_IT)
+{
+ uint32_t bitpos = 0x00, itmask = 0x00, usartreg = 0x00;
+ ITStatus bitstatus = RESET;
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_GET_IT(USART_IT));
+
+ /* The CTS interrupt is not available for UART4 and UART5 */
+ if (USART_IT == USART_IT_CTS)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+ /* Get the USART register index */
+ usartreg = (((uint8_t)USART_IT) >> 0x05);
+ /* Get the interrupt position */
+ itmask = USART_IT & IT_MASK;
+ itmask = (uint32_t)0x01 << itmask;
+
+ if (usartreg == 0x01) /* The IT is in CR1 register */
+ {
+ itmask &= USARTx->CR1;
+ }
+ else if (usartreg == 0x02) /* The IT is in CR2 register */
+ {
+ itmask &= USARTx->CR2;
+ }
+ else /* The IT is in CR3 register */
+ {
+ itmask &= USARTx->CR3;
+ }
+
+ bitpos = USART_IT >> 0x08;
+ bitpos = (uint32_t)0x01 << bitpos;
+ bitpos &= USARTx->SR;
+ if ((itmask != (uint16_t)RESET)&&(bitpos != (uint16_t)RESET))
+ {
+ bitstatus = SET;
+ }
+ else
+ {
+ bitstatus = RESET;
+ }
+
+ return bitstatus;
+}
+
+/**
+ * @brief Clears the USARTx's interrupt pending bits.
+ * @param USARTx: where x can be 1, 2, 3, 4, 5 or 6 to select the USART or
+ * UART peripheral.
+ * @param USART_IT: specifies the interrupt pending bit to clear.
+ * This parameter can be one of the following values:
+ * @arg USART_IT_CTS: CTS change interrupt (not available for UART4 and UART5)
+ * @arg USART_IT_LBD: LIN Break detection interrupt
+ * @arg USART_IT_TC: Transmission complete interrupt.
+ * @arg USART_IT_RXNE: Receive Data register not empty interrupt.
+ *
+ * @note PE (Parity error), FE (Framing error), NE (Noise error), ORE (OverRun
+ * error) and IDLE (Idle line detected) pending bits are cleared by
+ * software sequence: a read operation to USART_SR register
+ * (USART_GetITStatus()) followed by a read operation to USART_DR register
+ * (USART_ReceiveData()).
+ * @note RXNE pending bit can be also cleared by a read to the USART_DR register
+ * (USART_ReceiveData()).
+ * @note TC pending bit can be also cleared by software sequence: a read
+ * operation to USART_SR register (USART_GetITStatus()) followed by a write
+ * operation to USART_DR register (USART_SendData()).
+ * @note TXE pending bit is cleared only by a write to the USART_DR register
+ * (USART_SendData()).
+ *
+ * @retval None
+ */
+void USART_ClearITPendingBit(USART_TypeDef* USARTx, uint16_t USART_IT)
+{
+ uint16_t bitpos = 0x00, itmask = 0x00;
+ /* Check the parameters */
+ assert_param(IS_USART_ALL_PERIPH(USARTx));
+ assert_param(IS_USART_CLEAR_IT(USART_IT));
+
+ /* The CTS interrupt is not available for UART4 and UART5 */
+ if (USART_IT == USART_IT_CTS)
+ {
+ assert_param(IS_USART_1236_PERIPH(USARTx));
+ }
+
+ bitpos = USART_IT >> 0x08;
+ itmask = ((uint16_t)0x01 << (uint16_t)bitpos);
+ USARTx->SR = (uint16_t)~itmask;
+}
+
+/**
+ * @}
+ */
+
+/**
+ * @}
+ */
+
+/**
+ * @}
+ */
+
+/**
+ * @}
+ */
+
+/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/
projects / fw / stlink / blobdiff