Smartcard mode functions

Smartcard mode functions. More...

Collaboration diagram for Smartcard mode functions:

Functions
void	USART_SetGuardTime (USART_TypeDef *USARTx, uint8_t USART_GuardTime)
	Sets the specified USART guard time. More...
void	USART_SmartCardCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables the USART's Smart Card mode. More...
void	USART_SmartCardNACKCmd (USART_TypeDef *USARTx, FunctionalState NewState)
	Enables or disables NACK transmission. More...

Detailed Description

Smartcard mode functions.

 ===============================================================================
                              ##### 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 Prescaler 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
      (#) POptionally you can enable the parity error interrupt using the USART_ITConfig()
          function
      (#) PEnable the USART using the USART_Cmd() function.
      (#) PEnable the Smartcard NACK using the USART_SmartCardNACKCmd() function.
      (#) PEnable the Smartcard interface using the USART_SmartCardCmd() 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.
      -@- Smartcard mode is available on USART peripherals only (not available on UART4 
          and UART5 peripherals).

Function Documentation

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

Definition at line 920 of file stm32f4xx_usart.c.

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

Definition at line 939 of file stm32f4xx_usart.c.

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

Definition at line 964 of file stm32f4xx_usart.c.