Hello,
The RTS/CTS hardware functionality is supported by the Init_UART komponent or fsl_uart_hal component:
Init_UART component properties:
fsl_uart_hal functions:
/*!
* @brief Enables the UART receiver request-to-send functionality.
*
* This function allows the user to enable the UART receiver request-to-send (RTS) functionality.
* By enabling, it allows the RTS output to control the CTS input of the transmitting device to
* prevent receiver overrun. RTS is deasserted if the number of characters in the receiver data
* register (FIFO) is equal to or greater than RWFIFO[RXWATER]. RTS is asserted when the
* number of characters in the receiver data register (FIFO) is less than RWFIFO[RXWATER].
* Do not set both RXRTSE and TXRTSE.
*
* @param base UART module base pointer.
* @param enable Enable or disable receiver rts.
*/
static inline void UART_HAL_SetReceiverRtsCmd(UART_Type * base, bool enable)
{
UART_BWR_MODEM_RXRTSE(base, enable);
}
/*!
* @brief Enables the UART transmitter request-to-send functionality.
*
* This function allows the user to enable the UART transmitter request-to-send (RTS) functionality.
* When enabled, it allows the UART to control the RTS assertion before and after a transmission
* such that when a character is placed into an empty transmitter data buffer, RTS
* asserts one bit time before the start bit is transmitted. RTS deasserts one bit time after all
* characters in the transmitter data buffer and shift register are completely sent, including
* the last stop bit.
*
* @param base UART module base pointer.
* @param enable Enable or disable transmitter RTS.
*/
static inline void UART_HAL_SetTransmitterRtsCmd(UART_Type * base, bool enable)
{
UART_BWR_MODEM_TXRTSE(base, enable);
}
/*!
* @brief Configures the UART transmitter RTS polarity.
*
* This function allows the user configure the transmitter RTS polarity to be either active low
* or active high.
*
* @param base UART module base pointer.
* @param polarity The UART transmitter RTS polarity setting (false - active low,
* true - active high).
*/
static inline void UART_HAL_SetTransmitterRtsPolarityMode(UART_Type * base, bool polarity)
{
UART_BWR_MODEM_TXRTSPOL(base, polarity);
}
/*!
* @brief Enables the UART transmitter clear-to-send functionality.
*
* This function allows the user to enable the UART transmitter clear-to-send (CTS) functionality.
* When enabled, the transmitter checks the state of CTS each time it is ready to send a character.
* If CTS is asserted, the character is sent. If CTS is deasserted, the signal TXD remains in
* the mark state and transmission is delayed until CTS is asserted. Changes in CTS as a
* character is being sent do not affect its transmission.
*
* @param base UART module base pointer.
* @param enable Enable or disable transmitter CTS.
*/
static inline void UART_HAL_SetTransmitterCtsCmd(UART_Type * base, bool enable)
{
UART_BWR_MODEM_TXCTSE(base, enable);
}
The fsl_uart component does not support the RTS/CTS functionality. You can use this component together with fsl_uart_hal and enable RTS/CTS by using of RTS/CTS functions (see the list above).
Best Regards,
Marek Neuzil
