Switching lpuart baudrate issue for RT1052

[danielsu]

Hi Sir,

  We are developing product with RT1052 (MCUXpresso and SDK) and have the requirement to switch UART uart baudrate while running. However we found such issue to switch to some specific baudrates as below:

             initial baud after boot up               switched baudrate                           issue

                        9600                                     1200/2400                      transmit OK,but receive nothing

                        1200                                         1200                               no issue

                       9600                                     baudrate >=4800                   no issue

         We have tried the method of call LPUART_SetBaudRate and Deinit &init . Both can not work on switch to such low baudrate. We even try to change the clock source of uart module form pll to osc, but no effect.

        Can you help to explain this?

[jay_heng · Accepted solution]

If initial baudrate is 1200/2400, does it work properly on your side?

[danielsu]

Hi  Jay，

  Solved. The issue is caused by upper layer bytes timeout based on baudrate setting. Lower baudrate should have larger timeout value. 

   Thanks for your support.