stm32f0xx_usart.c

来自「stm32f0固件库」· C语言 代码 · 共 1,641 行 · 第 1/5 页

  /* Check the parameters */
  assert_param(IS_USART_ALL_PERIPH(USARTx));
  assert_param(IS_USART_MUTEMODE_WAKEUP(USART_WakeUp));

  USARTx->CR1 &= (uint32_t)~((uint32_t)USART_CR1_WAKE);
  USARTx->CR1 |= USART_WakeUp;
}

/**
  * @brief  Configure the the USART Address detection length.
  * @param  USARTx: where x can be 1 or 2 to select the USART peripheral.
  * @param  USART_AddressLength: specifies the USART address length detection.
  *   This parameter can be one of the following values:
  *     @arg USART_AddressLength_4b: 4-bit address length detection 
  *     @arg USART_AddressLength_7b: 7-bit address length detection 
  * @retval None
  */
void USART_AddressDetectionConfig(USART_TypeDef* USARTx, uint32_t USART_AddressLength)
{
  /* Check the parameters */
  assert_param(IS_USART_ALL_PERIPH(USARTx));
  assert_param(IS_USART_ADDRESS_DETECTION(USART_AddressLength));

  USARTx->CR2 &= (uint32_t)~((uint32_t)USART_CR2_ADDM7);
  USARTx->CR2 |= USART_AddressLength;
}

/**
  * @}
  */

/** @defgroup USART_Group6 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:
         (#) 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.
         (#) Enable the LIN mode using the USART_LINCmd() function.
         (#) Enable the USART using the USART_Cmd() function.
         (#) Send the break character using USART_SendBreak() function.
    [..] USART LIN Master receiver communication is possible through the 
         following procedure:
         (#) 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.
         (#) Configures the break detection length 
             using the USART_LINBreakDetectLengthConfig() function.
         (#) Enable the LIN mode using the USART_LINCmd() function.
         -@- 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.
         (#) Enable the USART using the USART_Cmd() function.

@endverbatim
  * @{
  */

/**
  * @brief  Sets the USART LIN Break detection length.
  * @param  USARTx: where x can be 1 to select the USART 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, uint32_t USART_LINBreakDetectLength)
{
  /* Check the parameters */
  assert_param(IS_USART_1_PERIPH(USARTx));
  assert_param(IS_USART_LIN_BREAK_DETECT_LENGTH(USART_LINBreakDetectLength));

  USARTx->CR2 &= (uint32_t)~((uint32_t)USART_CR2_LBDL);
  USARTx->CR2 |= USART_LINBreakDetectLength;  
}

/**
  * @brief  Enables or disables the USART's LIN mode.
  * @param  USARTx: where x can be 1 to select the USART 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_1_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 &= (uint32_t)~((uint32_t)USART_CR2_LINEN);
  }
}

/**
  * @}
  */

/** @defgroup USART_Group7 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:
         (#) Program the Baud rate, Word length, Stop bits, Parity, Mode transmitter 
             or Mode receiver and hardware flow control values using the USART_Init()
            function.
         (#) Configures the USART address using the USART_SetAddress() function.
         (#) Enable the half duplex mode using USART_HalfDuplexCmd() function.
         (#) Enable the USART using the USART_Cmd() function.
         -@- The RX pin is no longer used.
         -@- 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 or 2 to select the USART 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 &= (uint32_t)~((uint32_t)USART_CR3_HDSEL);
  }
}

/**
  * @}
  */


/** @defgroup USART_Group8 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:
         (#) Configures the Smartcard Prsecaler using the USART_SetPrescaler() 
             function.
         (#) Configures the Smartcard Guard Time using the USART_SetGuardTime() 
             function.
         (#) 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.
         (#) 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
         (#) Optionally you can enable the parity error interrupt using 
             the USART_ITConfig() function.
         (#) Enable the Smartcard NACK using the USART_SmartCardNACKCmd() function.
         (#) Enable the Smartcard interface using the USART_SmartCardCmd() function.
         (#) Enable the USART using the USART_Cmd() function.
    [..] 
  Please refer to the ISO 7816-3 specification for more details.
    [..] 
         (@) 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.
         (@) 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.

@endverbatim
  * @{
  */

/**
  * @brief  Sets the specified USART guard time.
  * @param  USARTx: where x can be 1 to select the USART 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_1_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 to select the USART 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_1_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 &= (uint32_t)~((uint32_t)USART_CR3_SCEN);
  }
}

/**
  * @brief  Enables or disables NACK transmission.
  * @param  USARTx: where x can be 1 to select the USART 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_1_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 &= (uint32_t)~((uint32_t)USART_CR3_NACK);
  }
}

/**
  * @brief  Sets the Smart Card number of retries in transmit and receive.
  * @param  USARTx: where x can be 1 to select the USART peripheral.
  * @param  USART_AutoCount: specifies the Smart Card auto retry count.
  * @retval None
  */
void USART_SetAutoRetryCount(USART_TypeDef* USARTx, uint8_t USART_AutoCount)
{    
  /* Check the parameters */
  assert_param(IS_USART_1_PERIPH(USARTx));
  assert_param(IS_USART_AUTO_RETRY_COUNTER(USART_AutoCount));
  /* Clear the USART auto retry count */
  USARTx->CR3 &= (uint32_t)~((uint32_t)USART_CR3_SCARCNT);
  /* Set the USART auto retry count*/
  USARTx->CR3 |= (uint32_t)((uint32_t)USART_AutoCount << 0x11);
}

/**
  * @brief  Sets the Smart Card Block length.
  * @param  USARTx: where x can be 1 to select the USART peripheral.
  * @param  USART_BlockLength: specifies the Smart Card block length.
  * @retval None
  */
void USART_SetBlockLength(USART_TypeDef* USARTx, uint8_t USART_BlockLength)
{    
  /* Check the parameters */
  assert_param(IS_USART_1_PERIPH(USARTx));

  /* Clear the Smart card block length */
  USARTx->RTOR &= (uint32_t)~((uint32_t)USART_RTOR_BLEN);
  /* Set the Smart Card block length */
  USARTx->RTOR |= (uint32_t)((uint32_t)USART_BlockLength << 0x18);
}

/**
  * @}
  */