Extended Initialization and Configuration Functions. More...

Functions
HAL_StatusTypeDef	HAL_RS485Ex_Init (UART_HandleTypeDef *huart, uint32_t Polarity, uint32_t AssertionTime, uint32_t DeassertionTime)
	Initialize the RS485 Driver enable feature according to the specified parameters in the UART_InitTypeDef and creates the associated handle.

Detailed Description

Extended Initialization and Configuration Functions.

===============================================================================
            ##### Initialization and Configuration functions #####
 ===============================================================================
    [..]
    This subsection provides a set of functions allowing to initialize the USARTx or the UARTy
    in asynchronous mode.
      (+) For the asynchronous mode the parameters below can be configured:
        (++) Baud Rate
        (++) Word Length
        (++) Stop Bit
        (++) Parity: If the parity is enabled, then the MSB bit of the data written
             in the data register is transmitted but is changed by the parity bit.
        (++) Hardware flow control
        (++) Receiver/transmitter modes
        (++) Over Sampling Method
        (++) One-Bit Sampling Method
      (+) For the asynchronous mode, the following advanced features can be configured as well:
        (++) TX and/or RX pin level inversion
        (++) data logical level inversion
        (++) RX and TX pins swap
        (++) RX overrun detection disabling
        (++) DMA disabling on RX error
        (++) MSB first on communication line
        (++) auto Baud rate detection
    [..]
    The HAL_RS485Ex_Init() API follows the UART RS485 mode configuration
     procedures (details for the procedures are available in reference manual).

Depending on the frame length defined by the M1 and M0 bits (7-bit, 8-bit or 9-bit), the possible UART formats are listed in the following table.

Table 1. UART frame format. +-----------------------------------------------------------------------+ | M1 bit | M0 bit | PCE bit | UART frame | |---------|---------|-----------|---------------------------------------| | 0 | 0 | 0 | | SB | 8 bit data | STB | | |---------|---------|-----------|---------------------------------------| | 0 | 0 | 1 | | SB | 7 bit data | PB | STB | | |---------|---------|-----------|---------------------------------------| | 0 | 1 | 0 | | SB | 9 bit data | STB | | |---------|---------|-----------|---------------------------------------| | 0 | 1 | 1 | | SB | 8 bit data | PB | STB | | |---------|---------|-----------|---------------------------------------| | 1 | 0 | 0 | | SB | 7 bit data | STB | | |---------|---------|-----------|---------------------------------------| | 1 | 0 | 1 | | SB | 6 bit data | PB | STB | | +-----------------------------------------------------------------------+

Function Documentation

HAL_StatusTypeDef HAL_RS485Ex_Init	(	UART_HandleTypeDef *	huart,
		uint32_t	Polarity,
		uint32_t	AssertionTime,
		uint32_t	DeassertionTime
	)

Initialize the RS485 Driver enable feature according to the specified parameters in the UART_InitTypeDef and creates the associated handle.

Parameters:

huart	UART handle.
Polarity	Select the driver enable polarity. This parameter can be one of the following values: UART_DE_POLARITY_HIGH DE signal is active high UART_DE_POLARITY_LOW DE signal is active low
AssertionTime	Driver Enable assertion time: 5-bit value defining the time between the activation of the DE (Driver Enable) signal and the beginning of the start bit. It is expressed in sample time units (1/8 or 1/16 bit time, depending on the oversampling rate)
DeassertionTime	Driver Enable deassertion time: 5-bit value defining the time between the end of the last stop bit, in a transmitted message, and the de-activation of the DE (Driver Enable) signal. It is expressed in sample time units (1/8 or 1/16 bit time, depending on the oversampling rate).

Return values:

HAL status

Definition at line 170 of file stm32l4xx_hal_uart_ex.c.

References __HAL_UART_DISABLE, __HAL_UART_ENABLE, __UART_HandleTypeDef::AdvancedInit, UART_AdvFeatureInitTypeDef::AdvFeatureInit, assert_param, __UART_HandleTypeDef::gState, HAL_UART_MspInit(), HAL_UART_STATE_BUSY, HAL_UART_STATE_RESET, __UART_HandleTypeDef::Instance, IS_UART_ASSERTIONTIME, IS_UART_DE_POLARITY, IS_UART_DEASSERTIONTIME, __UART_HandleTypeDef::Lock, __UART_HandleTypeDef::MspInitCallback, UART_ADVFEATURE_NO_INIT, UART_AdvFeatureConfig(), UART_CheckIdleState(), UART_CR1_DEAT_ADDRESS_LSB_POS, UART_CR1_DEDT_ADDRESS_LSB_POS, UART_InitCallbacksToDefault(), and UART_SetConfig().