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/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************

* File Name          : stm32f10x_usart.c

* Author             : MCD Application Team

* Date First Issued  : 09/29/2006

* Description        : This file provides all the USART firmware functions.

********************************************************************************

* History:

* 04/02/2007: V0.2

* 02/05/2007: V0.1

* 09/29/2006: V0.01

********************************************************************************

* THE PRESENT SOFTWARE 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 SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING

* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.

*******************************************************************************/

/* Includes ------------------------------------------------------------------*/

#include "stm32f10x_usart.h"

#include "stm32f10x_rcc.h"

/* Private typedef -----------------------------------------------------------*/

/* Private define ------------------------------------------------------------*/

/* USART RUN Mask */

#define CR1_RUN_Set               ((u16)0x2000)  /* USART Enable Mask */

#define CR1_RUN_Reset             ((u16)0xDFFF)  /* USART Disable Mask */

#define CR2_Address_Mask          ((u16)0xFFF0)  /* USART address Mask */

/* USART RWU Mask */

#define CR1_RWU_Set               ((u16)0x0002)  /* USART mute mode Enable Mask */

#define CR1_RWU_Reset             ((u16)0xFFFD)  /* USART mute mode Enable Mask */

#define USART_IT_Mask             ((u16)0x001F)  /* USART Interrupt Mask */

/* USART LIN Mask */

#define CR2_LINE_Set              ((u16)0x4000)  /* USART LIN Enable Mask */

#define CR2_LINE_Reset            ((u16)0xBFFF)  /* USART LIN Disable Mask */

#define CR1_SBK_Set               ((u16)0x0001)  /* USART Break Character send Mask */

/* USART SC Mask */

#define CR3_SCEN_Set              ((u16)0x0020)  /* USART SC Enable Mask */

#define CR3_SCEN_Reset            ((u16)0xFFDF)  /* USART SC Disable Mask */

/* USART SC NACK Mask */

#define CR3_NACK_Set              ((u16)0x0010)  /* USART SC NACK Enable Mask */

#define CR3_NACK_Reset            ((u16)0xFFEF)  /* USART SC NACK Disable Mask */

/* USART Half-Duplex Mask */

#define CR3_HDSEL_Set             ((u16)0x0008)  /* USART Half-Duplex Enable Mask */

#define CR3_HDSEL_Reset           ((u16)0xFFF7)  /* USART Half-Duplex Disable Mask */

/* USART IrDA Mask */

#define CR3_IRLP_Mask             ((u16)0xFFFB)  /* USART IrDA LowPower mode Mask */

/* USART LIN Break detection */

#define CR3_LBDL_Mask             ((u16)0xFFDF)  /* USART LIN Break detection Mask */

/* USART WakeUp Method  */

#define CR3_WAKE_Mask             ((u16)0xF7FF)  /* USART WakeUp Method Mask */

/* USART IrDA Mask */

#define CR3_IREN_Set              ((u16)0x0002)  /* USART IrDA Enable Mask */

#define CR3_IREN_Reset            ((u16)0xFFFD)  /* USART IrDA Disable Mask */

#define GTPR_LSB_Mask             ((u16)0x00FF)  /* Guard Time Register LSB Mask */

#define GTPR_MSB_Mask             ((u16)0xFF00)  /* Guard Time Register MSB Mask */

#define CR1_CLEAR_Mask            ((u16)0xE9F3)  /* USART CR1 Mask */

#define CR2_CLEAR_Mask            ((u16)0xC0FF)  /* USART CR2 Mask */

#define CR3_CLEAR_Mask            ((u16)0xFCFF)  /* USART CR3 Mask */

/* Private macro -------------------------------------------------------------*/

/* Private variables ---------------------------------------------------------*/

/* Private function prototypes -----------------------------------------------*/

/* Private functions ---------------------------------------------------------*/

/*******************************************************************************

* Function Name  : USART_DeInit

* Description    : Deinitializes the USARTx peripheral registers to their

*                  default reset values.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_DeInit(USART_TypeDef* USARTx)

{

  switch (*(u32*)&USARTx)

  {

    case USART1_BASE:

      RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART1, ENABLE);

      RCC_APB2PeriphResetCmd(RCC_APB2Periph_USART1, DISABLE);

      break;

    case USART2_BASE:

      RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART2, ENABLE);

      RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART2, DISABLE);

      break;

    case USART3_BASE:

      RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART3, ENABLE);

      RCC_APB1PeriphResetCmd(RCC_APB1Periph_USART3, DISABLE);

      break;

    default:

      break;

  }

}

/*******************************************************************************

* Function Name  : USART_Init

* Description    : Initializes the USARTx peripheral according to the specified

*                  parameters in the USART_InitStruct .

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART peripheral.

*                  - USART_InitStruct: pointer to a USART_InitTypeDef structure

*                    that contains the configuration information for the

*                    specified USART peripheral.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_Init(USART_TypeDef* USARTx, USART_InitTypeDef* USART_InitStruct)

{

  u32 tmpreg = 0x00, apbclock = 0x00;

  u32 integerdivider = 0x00;

  u32 fractionaldivider = 0x00;

  RCC_ClocksTypeDef RCC_ClocksStatus;

  /* Check the parameters */

  assert(IS_USART_WORD_LENGTH(USART_InitStruct->USART_WordLength));

  assert(IS_USART_STOPBITS(USART_InitStruct->USART_StopBits));

  assert(IS_USART_PARITY(USART_InitStruct->USART_Parity));

  assert(IS_USART_HARDWARE_FLOW_CONTROL(USART_InitStruct->USART_HardwareFlowControl));

  assert(IS_USART_MODE(USART_InitStruct->USART_Mode));

  assert(IS_USART_CLOCK(USART_InitStruct->USART_Clock));

  assert(IS_USART_CPOL(USART_InitStruct->USART_CPOL));

  assert(IS_USART_CPHA(USART_InitStruct->USART_CPHA));

  assert(IS_USART_LASTBIT(USART_InitStruct->USART_LastBit));

/*---------------------------- USART CR2 Configuration -----------------------*/

  tmpreg = USARTx->CR2;

  /* Clear STOP[13:12], CLKEN, CPOL, CPHA and LBCL bits */

  tmpreg &= CR2_CLEAR_Mask;

  /* Configure the USART Stop Bits, Clock, CPOL, CPHA and LastBit ------------*/

  /* Set STOP[13:12] bits according to USART_Mode 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 |= (u32)USART_InitStruct->USART_StopBits | USART_InitStruct->USART_Clock |

            USART_InitStruct->USART_CPOL | USART_InitStruct->USART_CPHA |

            USART_InitStruct->USART_LastBit;

  /* Write to USART CR2 */

  USARTx->CR2 = (u16)tmpreg;

/*---------------------------- USART CR1 Configuration -----------------------*/

  tmpreg = 0x00;

  tmpreg = USARTx->CR1;

  /* Clear M, PCE, PS, TE and RE bits */

  tmpreg &= 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 |= (u32)USART_InitStruct->USART_WordLength | USART_InitStruct->USART_Parity |

            USART_InitStruct->USART_Mode;

  /* Write to USART CR1 */

  USARTx->CR1 = (u16)tmpreg;

/*---------------------------- USART CR3 Configuration -----------------------*/

  tmpreg = 0x00;

  tmpreg = USARTx->CR3;

  /* Clear CTSE and RTSE bits */

  tmpreg &= 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 = (u16)tmpreg;

/*---------------------------- USART BRR Configuration -----------------------*/

  tmpreg = 0x00;

  /* Configure the USART Baud Rate -------------------------------------------*/

  RCC_GetClocksFreq(&RCC_ClocksStatus);

  if ((*(u32*)&USARTx) == USART1_BASE)

  {

    apbclock = RCC_ClocksStatus.PCLK2_Frequency;

  }

  else

  {

    apbclock = RCC_ClocksStatus.PCLK1_Frequency;

  }

  /* Determine the integer part */

  integerdivider = ((0x19 * apbclock) / (0x04 * (USART_InitStruct->USART_BaudRate)));

  tmpreg = (integerdivider / 0x64) << 0x04;

  /* Determine the fractional part */

  fractionaldivider = integerdivider - (0x64 * (tmpreg >> 0x04));

  tmpreg |= ((((fractionaldivider * 0x10) + 0x32) / 0x64)) & ((u8)0x0F);

  /* Write to USART BRR */

  USARTx->BRR = (u16)tmpreg;

}

/*******************************************************************************

* Function Name  : USART_StructInit

* Description    : Fills each USART_InitStruct member with its default value.

* Input          : - USART_InitStruct: pointer to a USART_InitTypeDef structure

*                    which will be initialized.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_StructInit(USART_InitTypeDef* USART_InitStruct)

{

  /* USART_InitStruct members default value */

  USART_InitStruct->USART_BaudRate = 0x2580; /* 9600 Baud */

  USART_InitStruct->USART_WordLength = USART_WordLength_8b;

  USART_InitStruct->USART_StopBits = USART_StopBits_1;

  USART_InitStruct->USART_Parity = USART_Parity_No ;

  USART_InitStruct->USART_HardwareFlowControl = USART_HardwareFlowControl_None;

  USART_InitStruct->USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

  USART_InitStruct->USART_Clock = USART_Clock_Disable;

  USART_InitStruct->USART_CPOL = USART_CPOL_Low;

  USART_InitStruct->USART_CPHA = USART_CPHA_1Edge;

  USART_InitStruct->USART_LastBit = USART_LastBit_Disable;

}

/*******************************************************************************

* Function Name  : USART_Cmd

* Description    : Enables or disables the specified USART peripheral.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                : - NewState: new state of the USARTx peripheral.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_Cmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the selected USART by setting the RUN bit in the CR1 register */

    USARTx->CR1 |= CR1_RUN_Set;

  }

  else

  {

    /* Disable the selected USART by clearing the RUN bit in the CR1 register */

    USARTx->CR1 &= CR1_RUN_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_ITConfig

* Description    : Enables or disables the specified USART interrupts.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_IT: specifies the USART interrupt sources to be

*                    enabled or disabled.

*                    This parameter can be one of the following values:

*                       - USART_IT_PE

*                       - USART_IT_TXE

*                       - USART_IT_TC

*                       - USART_IT_RXNE

*                       - USART_IT_IDLE

*                       - USART_IT_LBD

*                       - USART_IT_CTS

*                       - USART_IT_ERR

*                  - NewState: new state of the specified USARTx interrupts.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_ITConfig(USART_TypeDef* USARTx, u16 USART_IT, FunctionalState NewState)

{

  u32 usartreg = 0x00, itpos = 0x00, itmask = 0x00;

  u32 address = 0x00;

  /* Check the parameters */

  assert(IS_USART_CONFIG_IT(USART_IT));

  assert(IS_FUNCTIONAL_STATE(NewState));

  /* Get the USART register index */

  usartreg = (((u8)USART_IT) >> 0x05);

  /* Get the interrupt position */

  itpos = USART_IT & USART_IT_Mask;

  itmask = (((u32)0x01) << itpos);

  address = *(u32*)&(USARTx);

  if (usartreg == 0x01) /* The IT  is in CR1 register */

  {

    address += 0x0C;

  }

  else if (usartreg == 0x02) /* The IT  is in CR2 register */

  {

    address += 0x10;

  }

  else /* The IT  is in CR3 register */

  {

    address += 0x14;

  }

  if (NewState != DISABLE)

  {

    *(u32*)address  |= itmask;

  }

  else

  {

    *(u32*)address &= ~itmask;

  }

}

/*******************************************************************************

* Function Name  : USART_DMACmd

* Description    : Enables or disables the USART’s DMA interface.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_DMAReq: specifies the DMA request.

*                    This parameter can be any combination of the following values:

*                       - USART_DMAReq_Tx

*                       - USART_DMAReq_Rx

*                  - NewState: new state of the DMA Request sources.

*                   This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_DMACmd(USART_TypeDef* USARTx, u16 USART_DMAReq, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_USART_DMAREQ(USART_DMAReq));

  assert(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 &= (u16)~USART_DMAReq;

  }

}

/*******************************************************************************

* Function Name  : USART_SetAddress

* Description    : Sets the address of the USART node.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_Address: Indicates the address of the USART node.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SetAddress(USART_TypeDef* USARTx, u8 USART_Address)

{

  /* Check the parameters */

  assert(IS_USART_ADDRESS(USART_Address));

  /* Clear the USART address */

  USARTx->CR2 &= CR2_Address_Mask;

  /* Set the USART address node */

  USARTx->CR2 |= USART_Address;

}

/*******************************************************************************

* Function Name  : USART_WakeUpConfig

* Description    : Selects the USART WakeUp method.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_WakeUp: specifies the USART wakeup method.

*                    This parameter can be one of the following values:

*                        - USART_WakeUp_IdleLine

*                        - USART_WakeUp_AddressMark

* Output         : None

* Return         : None

*******************************************************************************/

void USART_WakeUpConfig(USART_TypeDef* USARTx, u16 USART_WakeUp)

{

  /* Check the parameters */

  assert(IS_USART_WAKEUP(USART_WakeUp));

  USARTx->CR1 &= CR3_WAKE_Mask;

  USARTx->CR1 |= USART_WakeUp;

}

/*******************************************************************************

* Function Name  : USART_ReceiverWakeUpCmd

* Description    : Determines if the USART is in mute mode or not.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the USART mode.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_ReceiverWakeUpCmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the mute mode USART by setting the RWU bit in the CR1 register */

    USARTx->CR1 |= CR1_RWU_Set;

  }

  else

  {

    /* Disable the mute mode USART by clearing the RWU bit in the CR1 register */

    USARTx->CR1 &= CR1_RWU_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_LINBreakDetectLengthConfig

* Description    : Sets the USART LIN Break detection length.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_LINBreakDetectLength: specifies the LIN break

*                    detection length.

*                    This parameter can be one of the following values:

*                       - USART_LINBreakDetectLength_10b

*                       - USART_LINBreakDetectLength_11b

* Output         : None

* Return         : None

*******************************************************************************/

void USART_LINBreakDetectLengthConfig(USART_TypeDef* USARTx, u16 USART_LINBreakDetectLength)

{

  /* Check the parameters */

  assert(IS_USART_LIN_BREAK_DETECT_LENGTH(USART_LINBreakDetectLength));

  USARTx->CR2 &= CR3_LBDL_Mask;

  USARTx->CR2 |= USART_LINBreakDetectLength;

}

/*******************************************************************************

* Function Name  : USART_LINCmd

* Description    : Enables or disables the USART’s LIN mode.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the USART LIN mode.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_LINCmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the LIN mode by setting the LINE bit in the CR2 register */

    USARTx->CR2 |= CR2_LINE_Set;

  }

  else

  {

    /* Disable the LIN mode by clearing the LINE bit in the CR2 register */

    USARTx->CR2 &= CR2_LINE_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_SendData

* Description    : Transmits signle data through the USARTx peripheral.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - Data: the data to transmit.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SendData(USART_TypeDef* USARTx, u16 Data)

{

  /* Check the parameters */

  assert(IS_USART_DATA(Data));

  /* Transmit Data */

  USARTx->DR = (Data & (u16)0x01FF);

}

/*******************************************************************************

* Function Name  : USART_ReceiveData

* Description    : Returns the most recent received data by the USARTx peripheral.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

* Output         : None

* Return         : The received data.

*******************************************************************************/

u16 USART_ReceiveData(USART_TypeDef* USARTx)

{

  /* Receive Data */

  return (u16)(USARTx->DR & (u16)0x01FF);

}

/*******************************************************************************

* Function Name  : USART_SendBreak

* Description    : Transmits break characters.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SendBreak(USART_TypeDef* USARTx)

{

  /* Send break characters */

  USARTx->CR1 |= CR1_SBK_Set;

}

/*******************************************************************************

* Function Name  : USART_SetGuardTime

* Description    : Sets the specified USART guard time.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_GuardTime: specifies the guard time.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SetGuardTime(USART_TypeDef* USARTx, u8 USART_GuardTime)

{

  /* Clear the USART Guard time */

  USARTx->GTPR &= GTPR_LSB_Mask;

  /* Set the USART guard time */

  USARTx->GTPR |= (u16)((u16)USART_GuardTime << 0x08);

}

/*******************************************************************************

* Function Name  : USART_SetPrescaler

* Description    : Sets the system clock prescaler.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_Prescaler: specifies the prescaler clock.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SetPrescaler(USART_TypeDef* USARTx, u8 USART_Prescaler)

{

  /* Clear the USART prescaler */

  USARTx->GTPR &= GTPR_MSB_Mask;

  /* Set the USART prescaler */

  USARTx->GTPR |= USART_Prescaler;

}

/*******************************************************************************

* Function Name  : USART_SmartCardCmd

* Description    : Enables or disables the USART’s Smart Card mode.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the Smart Card mode.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SmartCardCmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the SC mode by setting the SCEN bit in the CR3 register */

    USARTx->CR3 |= CR3_SCEN_Set;

  }

  else

  {

    /* Disable the SC mode by clearing the SCEN bit in the CR3 register */

    USARTx->CR3 &= CR3_SCEN_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_SmartCardNACKCmd

* Description    : Enables or disables NACK transmission.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the NACK transmission.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_SmartCardNACKCmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the NACK transmission by setting the NACK bit in the CR3 register */

    USARTx->CR3 |= CR3_NACK_Set;

  }

  else

  {

    /* Disable the NACK transmission by clearing the NACK bit in the CR3 register */

    USARTx->CR3 &= CR3_NACK_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_HalfDuplexCmd

* Description    : Enables or disables the USART’s Half Duplex communication.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the USART Communication.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_HalfDuplexCmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the Half-Duplex mode by setting the HDSEL bit in the CR3 register */

    USARTx->CR3 |= CR3_HDSEL_Set;

  }

  else

  {

    /* Disable the Half-Duplex mode by clearing the HDSEL bit in the CR3 register */

    USARTx->CR3 &= CR3_HDSEL_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_IrDAConfig

* Description    : Configures the USART’s IrDA interface.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_IrDAMode: specifies the IrDA mode.

*                    This parameter can be one of the following values:

*                       - USART_IrDAMode_LowPower

*                       - USART_IrDAMode_Normal

* Output         : None

* Return         : None

*******************************************************************************/

void USART_IrDAConfig(USART_TypeDef* USARTx, u16 USART_IrDAMode)

{

  /* Check the parameters */

  assert(IS_USART_IRDA_MODE(USART_IrDAMode));

  USARTx->CR3 &= CR3_IRLP_Mask;

  USARTx->CR3 |= USART_IrDAMode;

}

/*******************************************************************************

* Function Name  : USART_IrDACmd

* Description    : Enables or disables the USART’s IrDA interface.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - NewState: new state of the IrDA mode.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void USART_IrDACmd(USART_TypeDef* USARTx, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the IrDA mode by setting the IREN bit in the CR3 register */

    USARTx->CR3 |= CR3_IREN_Set;

  }

  else

  {

    /* Disable the IrDA mode by clearing the IREN bit in the CR3 register */

    USARTx->CR3 &= CR3_IREN_Reset;

  }

}

/*******************************************************************************

* Function Name  : USART_GetFlagStatus

* Description    : Checks whether the specified USART flag is set or not.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_FLAG: specifies the flag to check.

*                    This parameter can be one of the following values:

*                       - USART_FLAG_CTS

*                       - USART_FLAG_LBD

*                       - USART_FLAG_TXE

*                       - USART_FLAG_TC

*                       - USART_FLAG_RXNE

*                       - USART_FLAG_IDLE

*                       - USART_FLAG_ORE

*                       - USART_FLAG_NE

*                       - USART_FLAG_FE

*                       - USART_FLAG_PE

* Output         : None

* Return         : The new state of USART_FLAG (SET or RESET).

*******************************************************************************/

FlagStatus USART_GetFlagStatus(USART_TypeDef* USARTx, u16 USART_FLAG)

{

  FlagStatus bitstatus = RESET;

  /* Check the parameters */

  assert(IS_USART_FLAG(USART_FLAG));

  if ((USARTx->SR & USART_FLAG) != (u16)RESET)

  {

    bitstatus = SET;

  }

  else

  {

    bitstatus = RESET;

  }

  return bitstatus;

}

/*******************************************************************************

* Function Name  : USART_ClearFlag

* Description    : Clears the USARTx's pending flags.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_FLAG: specifies the flag to clear.

*                    This parameter can be any combination of the following values:

*                       - USART_FLAG_CTS

*                       - USART_FLAG_LBD

*                       - USART_FLAG_TXE

*                       - USART_FLAG_TC

*                       - USART_FLAG_RXNE

*                       - USART_FLAG_IDLE

*                       - USART_FLAG_ORE

*                       - USART_FLAG_NE

*                       - USART_FLAG_FE

*                       - USART_FLAG_PE

* Output         : None

* Return         : None

*******************************************************************************/

void USART_ClearFlag(USART_TypeDef* USARTx, u16 USART_FLAG)

{

  /* Check the parameters */

  assert(IS_USART_CLEAR_FLAG(USART_FLAG));

  USARTx->SR &= (u16)~USART_FLAG;

}

/*******************************************************************************

* Function Name  : USART_GetITStatus

* Description    : Checks whether the specified USART interrupt has occurred or not.

* Input          : - USARTx: where x can be 1, 2 or 3 to select the USART

*                    peripheral.

*                  - USART_IT: specifies the USART interrupt source to check.

*                    This parameter can be one of the following values:

*                       - USART_IT_PE

*                       - USART_IT_TXE

*                       - USART_IT_TC

*                       - USART_IT_RXNE

*                       - USART_IT_IDLE

*                       - USART_IT_LBD

*                       - USART_IT_CTS

*                       - USART_IT_ORE

*                       - USART_IT_NE

*                       - USART_IT_FE

* Output         : None

* Return         : The new state of USART_IT (SET or RESET).

*******************************************************************************/

ITStatus USART_GetITStatus(USART_TypeDef* USARTx, u16 USART_IT)

{

  u32 bitpos = 0x00, itmask = 0x00, usartreg = 0;

  ITStatus bitstatus = RESET;

  /* Check the parameters */

  assert(IS_USART_IT(USART_IT));

  /* Get the USART register index */

  usartreg = (((u8)USART_IT) >> 0x05);

  /* Get the interrupt position */

  itmask = USART_IT & USART_IT_Mask;

  itmask = (u32)0x01 << itmask;