Regarding stm32h750 USART IDLE

[martin_xu]

Hello,

     BIT4 IDLE Bit of USART interrupt and status register (USART_ISR) 

    

        Could you please explain what is  condition about  "an idle Line is detected"?

        How long time for the  UART RX Pin on idle state? 

        the idle is high level?

Thanks,

Martin 

[KDJEM.1]

Hello @martin_xu ,

 

The Idle line is detected when there is no data transmission on the communication line.

Setting the TE bit drives the USART to send an idle frame before the first data frame.

If the USART is activated while the line is IDLE, the idle state is detected after the duration of one IDLE frame (not only after the reception of one character frame)

For more explanation I advise you to refer to Reference manual and precisely  Figure 571 Figure 571. Word length programming.

Please let me know if my reply answer your request.

Thank you.

Kaouthar