USART
[STM32F4xx_StdPeriph_Driver]

USART driver modules. More...

Data Structures
struct	USART_InitTypeDef
	USART Init Structure definition. More...
struct	USART_ClockInitTypeDef
	USART Clock Init Structure definition. More...
Modules
	USART_Exported_Constants
	USART_Private_Functions
Defines
#define	CR1_CLEAR_MASK
#define	CR2_CLOCK_CLEAR_MASK
#define	CR3_CLEAR_MASK ((uint16_t)(USART_CR3_RTSE \| USART_CR3_CTSE))
#define	IT_MASK ((uint16_t)0x001F)
Functions
void	USART_DeInit (USART_TypeDef *USARTx)
	Deinitializes the USARTx peripheral registers to their default reset values.
void	USART_Init (USART_TypeDef USARTx, USART_InitTypeDef USART_InitStruct)
	Initializes the USARTx peripheral according to the specified parameters in the USART_InitStruct .
void	USART_StructInit (USART_InitTypeDef *USART_InitStruct)
	Fills each USART_InitStruct member with its default value.
void	USART_ClockInit (USART_TypeDef USARTx, USART_ClockInitTypeDef USART_ClockInitStruct)
	Initializes the USARTx peripheral Clock according to the specified parameters in the USART_ClockInitStruct .
void	USART_ClockStructInit (USART_ClockInitTypeDef *USART_ClockInitStruct)
	Fills each USART_ClockInitStruct member with its default value.
void	USART_Cmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the specified USART peripheral.
void	USART_SetPrescaler (USART_TypeDef *USARTx, uint8_t USART_Prescaler)
	Sets the system clock prescaler.
void	USART_OverSampling8Cmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's 8x oversampling mode.
void	USART_OneBitMethodCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's one bit sampling method.
void	USART_SendData (USART_TypeDef *USARTx, uint16_t Data)
	Transmits single data through the USARTx peripheral.
uint16_t	USART_ReceiveData (USART_TypeDef *USARTx)
	Returns the most recent received data by the USARTx peripheral.
void	USART_SetAddress (USART_TypeDef *USARTx, uint8_t USART_Address)
	Sets the address of the USART node.
void	USART_WakeUpConfig (USART_TypeDef *USARTx, uint16_t USART_WakeUp)
	Selects the USART WakeUp method.
void	USART_ReceiverWakeUpCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Determines if the USART is in mute mode or not.
void	USART_LINBreakDetectLengthConfig (USART_TypeDef *USARTx, uint16_t USART_LINBreakDetectLength)
	Sets the USART LIN Break detection length.
void	USART_LINCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's LIN mode.
void	USART_SendBreak (USART_TypeDef *USARTx)
	Transmits break characters.
void	USART_HalfDuplexCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's Half Duplex communication.
void	USART_SmartCardCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's Smart Card mode.
void	USART_SmartCardNACKCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables NACK transmission.
void	USART_SetGuardTime (USART_TypeDef *USARTx, uint8_t USART_GuardTime)
	Sets the specified USART guard time.
void	USART_IrDAConfig (USART_TypeDef *USARTx, uint16_t USART_IrDAMode)
	Configures the USART's IrDA interface.
void	USART_IrDACmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's IrDA interface.
void	USART_DMACmd (USART_TypeDef *USARTx, uint16_t USART_DMAReq, FunctionalState NewState)
	Enables or disables the USART's DMA interface.
void	USART_ITConfig (USART_TypeDef *USARTx, uint16_t USART_IT, FunctionalState NewState)
	Enables or disables the specified USART interrupts.
FlagStatus	USART_GetFlagStatus (USART_TypeDef *USARTx, uint16_t USART_FLAG)
	Checks whether the specified USART flag is set or not.
void	USART_ClearFlag (USART_TypeDef *USARTx, uint16_t USART_FLAG)
	Clears the USARTx's pending flags.
ITStatus	USART_GetITStatus (USART_TypeDef *USARTx, uint16_t USART_IT)
	Checks whether the specified USART interrupt has occurred or not.
void	USART_ClearITPendingBit (USART_TypeDef *USARTx, uint16_t USART_IT)
	Clears the USARTx's interrupt pending bits.

Detailed Description

USART driver modules.

Define Documentation

#define CR1_CLEAR_MASK

Value:

((uint16_t)(USART_CR1_M | USART_CR1_PCE | \
                                              USART_CR1_PS | USART_CR1_TE | \
                                              USART_CR1_RE))

< USART CR1 register clear Mask ((~(uint16_t)0xE9F3)) USART CR2 register clock bits clear Mask ((~(uint16_t)0xF0FF))

#define CR2_CLOCK_CLEAR_MASK

Value:

((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

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 or 6 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

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 or 6 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

void USART_ClockInit	(	USART_TypeDef *	USARTx,
		USART_ClockInitTypeDef *	USART_ClockInitStruct
	)

Initializes the USARTx peripheral Clock according to the specified parameters in the USART_ClockInitStruct .

Parameters:

	USARTx,:	where x can be 1, 2, 3 or 6 to select the USART peripheral.
	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.

Return values:

None

void USART_ClockStructInit ( USART_ClockInitTypeDef * USART_ClockInitStruct )

Fills each USART_ClockInitStruct member with its default value.

Parameters:

USART_ClockInitStruct,:

pointer to a USART_ClockInitTypeDef structure which will be initialized.

Return values:

None

void USART_Cmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the specified USART peripheral.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USARTx peripheral. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_DeInit ( USART_TypeDef * USARTx )

Deinitializes the USARTx peripheral registers to their default reset values.

Parameters:

USARTx,:

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

Return values:

None

void USART_DMACmd	(	USART_TypeDef *	USARTx,
		uint16_t	USART_DMAReq,
		FunctionalState	NewState
	)

Enables or disables the USART's DMA interface.

Parameters:

USARTx,:

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

USART_DMAReq,:

specifies the DMA request. This parameter can be any combination of the following values:

USART_DMAReq_Tx: USART DMA transmit request
USART_DMAReq_Rx: USART DMA receive request

NewState,:

new state of the DMA Request sources. This parameter can be: ENABLE or DISABLE.

Return values:

None

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 or 6 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).

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 or 6 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).

void USART_HalfDuplexCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's Half Duplex communication.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USART Communication. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_Init	(	USART_TypeDef *	USARTx,
		USART_InitTypeDef *	USART_InitStruct
	)

Initializes the USARTx peripheral according to the specified parameters in the USART_InitStruct .

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	USART_InitStruct,:	pointer to a USART_InitTypeDef structure that contains the configuration information for the specified USART peripheral.

Return values:

None

void USART_IrDACmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's IrDA interface.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the IrDA mode. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_IrDAConfig	(	USART_TypeDef *	USARTx,
		uint16_t	USART_IrDAMode
	)

Configures the USART's IrDA interface.

Parameters:

USARTx,:

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

USART_IrDAMode,:

specifies the IrDA mode. This parameter can be one of the following values:

USART_IrDAMode_LowPower
USART_IrDAMode_Normal

Return values:

None

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 or 6 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

void USART_LINBreakDetectLengthConfig	(	USART_TypeDef *	USARTx,
		uint16_t	USART_LINBreakDetectLength
	)

Sets the USART LIN Break detection length.

Parameters:

USARTx,:

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

USART_LINBreakDetectLength,:

specifies the LIN break detection length. This parameter can be one of the following values:

USART_LINBreakDetectLength_10b: 10-bit break detection
USART_LINBreakDetectLength_11b: 11-bit break detection

Return values:

None

void USART_LINCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's LIN mode.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USART LIN mode. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_OneBitMethodCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's one bit sampling method.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USART one bit sampling method. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_OverSampling8Cmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

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.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USART 8x oversampling mode. This parameter can be: ENABLE or DISABLE.

Return values:

None

uint16_t USART_ReceiveData ( USART_TypeDef * USARTx )

Returns the most recent received data by the USARTx peripheral.

Parameters:

USARTx,:

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

Return values:

The

received data.

void USART_ReceiverWakeUpCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Determines if the USART is in mute mode or not.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the USART mute mode. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_SendBreak ( USART_TypeDef * USARTx )

Transmits break characters.

Parameters:

USARTx,:

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

Return values:

None

void USART_SendData	(	USART_TypeDef *	USARTx,
		uint16_t	Data
	)

Transmits single data through the USARTx peripheral.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	Data,:	the data to transmit.

Return values:

None

void USART_SetAddress	(	USART_TypeDef *	USARTx,
		uint8_t	USART_Address
	)

Sets the address of the USART node.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	USART_Address,:	Indicates the address of the USART node.

Return values:

None

void USART_SetGuardTime	(	USART_TypeDef *	USARTx,
		uint8_t	USART_GuardTime
	)

Sets the specified USART guard time.

Parameters:

	USARTx,:	where x can be 1, 2, 3 or 6 to select the USART or UART peripheral.
	USART_GuardTime,:	specifies the guard time.

Return values:

None

void USART_SetPrescaler	(	USART_TypeDef *	USARTx,
		uint8_t	USART_Prescaler
	)

Sets the system clock prescaler.

Parameters:

	USARTx,:	where x can be 1, 2, 3, 4, 5 or 6 to select the USART or UART peripheral.
	USART_Prescaler,:	specifies the prescaler clock.

Note:: The function is used for IrDA mode with UART4 and UART5.

Return values:

None

void USART_SmartCardCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables the USART's Smart Card mode.

Parameters:

	USARTx,:	where x can be 1, 2, 3 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the Smart Card mode. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_SmartCardNACKCmd	(	USART_TypeDef *	USARTx,
		FunctionalState	NewState
	)

Enables or disables NACK transmission.

Parameters:

	USARTx,:	where x can be 1, 2, 3 or 6 to select the USART or UART peripheral.
	NewState,:	new state of the NACK transmission. This parameter can be: ENABLE or DISABLE.

Return values:

None

void USART_StructInit ( USART_InitTypeDef * USART_InitStruct )

Fills each USART_InitStruct member with its default value.

Parameters:

USART_InitStruct,:

pointer to a USART_InitTypeDef structure which will be initialized.

Return values:

None

void USART_WakeUpConfig	(	USART_TypeDef *	USARTx,
		uint16_t	USART_WakeUp
	)

Selects the USART WakeUp method.

Parameters:

USARTx,:

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

USART_WakeUp,:

specifies the USART wakeup method. This parameter can be one of the following values:

USART_WakeUp_IdleLine: WakeUp by an idle line detection
USART_WakeUp_AddressMark: WakeUp by an address mark

Return values:

None

USART [STM32F4xx_StdPeriph_Driver]

Data Structures

Modules

Defines

Functions

Detailed Description

Define Documentation

Function Documentation

USART
[STM32F4xx_StdPeriph_Driver]