Interrupts and flags management functions. More...

Collaboration diagram for Interrupts and flags management functions:

Functions
void	USART_ClearFlag (USART_TypeDef *USARTx, uint16_t USART_FLAG)
	Clears the USARTx's pending flags. More...

void	USART_ClearITPendingBit (USART_TypeDef *USARTx, uint16_t USART_IT)
	Clears the USARTx's interrupt pending bits. More...

FlagStatus	USART_GetFlagStatus (USART_TypeDef *USARTx, uint16_t USART_FLAG)
	Checks whether the specified USART flag is set or not. More...

ITStatus	USART_GetITStatus (USART_TypeDef *USARTx, uint16_t USART_IT)
	Checks whether the specified USART interrupt has occurred or not. More...

void	USART_IrDACmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's IrDA interface. More...

void	USART_IrDAConfig (USART_TypeDef *USARTx, uint32_t USART_IrDAMode)
	Configures the USART's IrDA interface. More...

void	USART_ITConfig (USART_TypeDef *USARTx, uint16_t USART_IT, FunctionalState NewState)
	Enables or disables the specified USART interrupts. More...

Detailed Description

Interrupts and flags management functions.

IrDA mode functions.

 ===============================================================================
            ##### 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:
      (#) USART_FLAG_TXE : to indicate the status of the transmit buffer register
      (#) USART_FLAG_RXNE : to indicate the status of the receive buffer register
      (#) USART_FLAG_TC : to indicate the status of the transmit operation
      (#) USART_FLAG_IDLE : to indicate the status of the Idle Line             
      (#) USART_FLAG_CTS : to indicate the status of the nCTS input
      (#) USART_FLAG_LBD : to indicate the status of the LIN break detection
      (#) USART_FLAG_NE : to indicate if a noise error occur
      (#) USART_FLAG_FE : to indicate if a frame error occur
      (#) USART_FLAG_PE : to indicate if a parity error occur
      (#) 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:

        (##) USART_IT_TXE : to indicate the status of the transmit buffer register
        (##) USART_IT_RXNE : to indicate the status of the receive buffer register
        (##) USART_IT_TC : to indicate the status of the transmit operation
        (##) USART_IT_IDLE : to indicate the status of the Idle Line             
        (##) USART_IT_CTS : to indicate the status of the nCTS input
        (##) USART_IT_LBD : to indicate the status of the LIN break detection
        (##) USART_IT_NE : to indicate if a noise error occur
        (##) USART_IT_FE : to indicate if a frame error occur
        (##) USART_IT_PE : to indicate if a parity error occur
        (##) USART_IT_ORE : to indicate if an Overrun error occur

      (#) Interrupt Source:

        (##) USART_IT_TXE : specifies the interrupt source for the Tx buffer empty 
                            interrupt. 
        (##) USART_IT_RXNE : specifies the interrupt source for the Rx buffer not 
                             empty interrupt.
        (##) USART_IT_TC : specifies the interrupt source for the Transmit complete 
                           interrupt. 
        (##) USART_IT_IDLE : specifies the interrupt source for the Idle Line interrupt.             
        (##) USART_IT_CTS : specifies the interrupt source for the CTS interrupt. 
        (##) USART_IT_LBD : specifies the interrupt source for the LIN break detection
                            interrupt. 
        (##) USART_IT_PE : specifies the interrupt source for the parity error interrupt. 
        (##) USART_IT_ERR :  specifies the interrupt source for the errors interrupt.

      -@@- 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:
      (#) USART_DMAReq_Tx: specifies the Tx buffer DMA transfer request
      (#) 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);

 ===============================================================================
                        ##### 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:
         (#) Program the Baud rate, Word length = 8 bits, Stop bits, Parity, 
             Transmitter/Receiver modes and hardware flow control values using 
             the USART_Init() function.
         (#) Configures the IrDA pulse width by configuring the prescaler using  
             the USART_SetPrescaler() function.
         (#) Configures the IrDA  USART_IrDAMode_LowPower or USART_IrDAMode_Normal 
             mode using the USART_IrDAConfig() function.
         (#) Enable the IrDA using the USART_IrDACmd() function.
         (#) Enable the USART using the USART_Cmd() function.         
    [..]
    (@) A pulse of width less than two and greater than one PSC period(s) may or 
        may not be rejected.
    (@) 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).
    (@) 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.

Function Documentation

void USART_ClearFlag	(	USART_TypeDef *	USARTx,
		uint16_t	USART_FLAG
	)

Clears the USARTx's pending flags.

Parameters

USARTx	where x can be 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or UART peripheral.
USART_FLAG	specifies the flag to clear. This parameter can be any combination of the following values: USART_FLAG_CTS: CTS Change flag (not available for UART4 and UART5). USART_FLAG_LBD: LIN Break detection flag. USART_FLAG_TC: Transmission Complete flag. 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()).; RXNE flag can be also cleared by a read to the USART_DR register (USART_ReceiveData()).; 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()).; TXE flag is cleared only by a write to the USART_DR register (USART_SendData()).

Return values

None

Definition at line 1344 of file stm32f4xx_usart.c.

void USART_ClearITPendingBit	(	USART_TypeDef *	USARTx,
		uint16_t	USART_IT
	)

Clears the USARTx's interrupt pending bits.

Parameters

USARTx	where x can be 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or UART peripheral.
USART_IT	specifies the interrupt pending bit to clear. This parameter can be one of the following values: USART_IT_CTS: CTS change interrupt (not available for UART4 and UART5) USART_IT_LBD: LIN Break detection interrupt USART_IT_TC: Transmission complete interrupt. 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()).; RXNE pending bit can be also cleared by a read to the USART_DR register (USART_ReceiveData()).; 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()).; TXE pending bit is cleared only by a write to the USART_DR register (USART_SendData()).

Return values

None

Definition at line 1452 of file stm32f4xx_usart.c.

FlagStatus USART_GetFlagStatus	(	USART_TypeDef *	USARTx,
		uint16_t	USART_FLAG
	)

Checks whether the specified USART flag is set or not.

Parameters

USARTx where x can be 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or UART peripheral.

USART_FLAG

specifies the flag to check. This parameter can be one of the following values:

USART_FLAG_CTS: CTS Change flag (not available for UART4 and UART5)
USART_FLAG_LBD: LIN Break detection flag
USART_FLAG_TXE: Transmit data register empty flag
USART_FLAG_TC: Transmission Complete flag
USART_FLAG_RXNE: Receive data register not empty flag
USART_FLAG_IDLE: Idle Line detection flag
USART_FLAG_ORE: OverRun Error flag
USART_FLAG_NE: Noise Error flag
USART_FLAG_FE: Framing Error flag
USART_FLAG_PE: Parity Error flag

Return values

The	new state of USART_FLAG (SET or RESET).

Definition at line 1295 of file stm32f4xx_usart.c.

ITStatus USART_GetITStatus	(	USART_TypeDef *	USARTx,
		uint16_t	USART_IT
	)

Checks whether the specified USART interrupt has occurred or not.

Parameters

USARTx where x can be 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or UART peripheral.

USART_IT

specifies the USART interrupt source to check. This parameter can be one of the following values:

USART_IT_CTS: CTS change interrupt (not available for UART4 and UART5)
USART_IT_LBD: LIN Break detection interrupt
USART_IT_TXE: Transmit Data Register empty interrupt
USART_IT_TC: Transmission complete interrupt
USART_IT_RXNE: Receive Data register not empty interrupt
USART_IT_IDLE: Idle line detection interrupt
USART_IT_ORE_RX : OverRun Error interrupt if the RXNEIE bit is set
USART_IT_ORE_ER : OverRun Error interrupt if the EIE bit is set
USART_IT_NE: Noise Error interrupt
USART_IT_FE: Framing Error interrupt
USART_IT_PE: Parity Error interrupt

Return values

The	new state of USART_IT (SET or RESET).

Definition at line 1378 of file stm32f4xx_usart.c.

void USART_IrDACmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's IrDA interface.

Parameters

USARTx	Select the USART peripheral. This parameter can be one of the following values: USART1 or USART2 or USART3 or UART4 or UART5.
NewState	new state of the IrDA mode. This parameter can be: ENABLE or DISABLE.

Return values

None

Definition at line 1437 of file stm32f30x_usart.c.

void USART_IrDAConfig	(	USART_TypeDef *	USARTx,
		uint32_t	USART_IrDAMode
	)

Configures the USART's IrDA interface.

Parameters

USARTx	Select the USART peripheral. This parameter can be one of the following values: USART1 or USART2 or USART3 or UART4 or UART5.
USART_IrDAMode	specifies the IrDA mode. This parameter can be one of the following values: USART_IrDAMode_LowPower USART_IrDAMode_Normal

Return values

None

Definition at line 1419 of file stm32f30x_usart.c.

void USART_ITConfig	(	USART_TypeDef *	USARTx,
		uint16_t	USART_IT,
		FunctionalState	NewState
	)

Enables or disables the specified USART interrupts.

Parameters

USARTx	where x can be 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or UART peripheral.
USART_IT	specifies the USART interrupt sources to be enabled or disabled. This parameter can be one of the following values: USART_IT_CTS: CTS change interrupt USART_IT_LBD: LIN Break detection interrupt USART_IT_TXE: Transmit Data Register empty interrupt USART_IT_TC: Transmission complete interrupt USART_IT_RXNE: Receive Data register not empty interrupt USART_IT_IDLE: Idle line detection interrupt USART_IT_PE: Parity Error interrupt USART_IT_ERR: Error interrupt(Frame error, noise error, overrun error)
NewState	new state of the specified USARTx interrupts. This parameter can be: ENABLE or DISABLE.

Return values

None

Definition at line 1231 of file stm32f4xx_usart.c.

Functions

Detailed Description

Function Documentation