• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 30 subscribers
  • Views 220 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

MSPM0G3507: UART Loopback mode

Eileen Hu
Prodigy 75 points
Part Number: MSPM0G3507
Other Parts Discussed in Thread: SYSCONFIG

Tool/software:

According to TRM, when Internal Loopback is enabled, data transmitted on the TX output is not propagated to the TX IO pin.

But when I use this function, there are still transmission signal in the TX IO pin can be tested by me.

I use the SDK routine 'uart_internal_loopback_standby_restore_LP_MSPM0G3507_nortos_ticlang', and I test the TX IO pin PB2 in BoosterPack of LP_MSPM0G3507 with a logic analyzer.

I would like to know why the actual situation doesn't match the TRM. Is there any misunderstanding?

  • +1
    TI__Expert 8260 points

    That may be the issue of SysConfig.

    In the code generated by SysConfig, IOs are still configured as UART TX/RX.

    You can try to remove these code manually. 

  • 0 in reply to Yuhao Zhao
    TI__Prodigy 75 points

    Hi Yuhao,

    After I remove code manually, no more signal on the TX IO pin. Thank you!

    But is there a way to configure this GPIO directly by SysConfig not to be UART but something else, or it just can be changed manually?

    Regards,

    Eileen

  • 0 in reply to Eileen Hu
    TI__Expert 8260 points

    Just out of curiosity, are you using the Loopback mode in your application? And what is it used for?

    Actually I usually only consider it as a testing mode.

    But if this is further needed, I think SysConfig should support to configure the IO seperately, and I will feedback to our team.

  • 0 in reply to Yuhao Zhao
    TI__Prodigy 75 points

    Hi Yuhao,

    I am just a beginner in M0 now and have this question here, and there is no practical application.

    Thank you for your solution.

    Regards,

    Eileen

  • 0 in reply to Eileen Hu
    TI__Prodigy 75 points

    By the way, when I learned the routine uart_rw_multibyte_fifo_poll, I referred to the MSPM0 Academy of SDK, which says the code example uses the M0 UART’s internal loopback mode so there are no LaunchPad jumpers to configure.

    But the routine's Sysconfig doesn't enable internal loopback so that it fails to function without LaunchPad jumpers. 

    It may need to be revised.