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.

  • Resolved

IWR6843: RS232 connectivity issue

Intellectual 260 points

Replies: 17

Views: 350

Part Number: IWR6843

Hello!

I have a trouble to activate our IWR6843 test module which is composed of IWR6843 boost B'd and RF module.

Basically, the circuit was reviewed and confirmed by TI. The only different point compared with TI's reference circuit is warmRst pull-up resistor is not connected in our module. [ SOP0, 1 are closed, SOP2 is open for a DCA B'd connection]

Is this root cause? The issue is a RS232 connectivity in mmwaveStudio.

And there is no oscillation of a 40MHz crystal on module board.

Each of 1v4_synth and vout_PA is 1.37V and 1.0V. And the 1v4_APLL and VBGAP output are 0V.

This case is very similar with "IWR1642: no crystal oscillation" that I have seen on E2E forum.

However, I couldn't notice the solution to resolve this issue.

Please let me know how to resolve it.

I'm looking forward to hearing from you.


Thank you!


Regards,

  • Hi,

    • Also will it be possible to share a picture of your setup?
    • Can you connect to the UART COM port using Teraterm or similar emulation software?
    • Is there any firmware running on the device? Can you confirm you have erased the flash before trying to run with DCA?

    Regards,

    Charles O

     

  • In reply to Charles Oladimeji:

    Hi,


    I can't upload the setup image because of security issues.


    Basically, the connection is same as DCA B'd connection. In my case, the RF and Booster B'd are combined by single module. So, only DCA connection is needed for data acqusition.


    It contains only one 60-pin connecter for DCA connection. [RF+XDS110 Chipset] <--60pin--> [DCA]


    I have tried to connect UART COM port using Teraterm. But there is no response.

    Is there any other things what I have to check?

    Please let me know that.

    Regards,

  • In reply to odors:

    Hi,

    1.  Were you able to debug the board via JTAG?
    2.  When you change the board to flashing mode, were you able to program it?
    3. lastly after programming it and changing the SOP back to functional mode, do you get any output on the UART terminal?

    Regards,

    Charles O

     

  • In reply to Charles Oladimeji:

    Hi,

    I have done the JTAG connection test.

    But Error is occurred as listed below.

    Please, comment to me for resolving problem.

    Regards,

    -----[An error has occurred and this utility has aborted]--------------------

    This error is generated by TI's USCIF driver or utilities.

    The value is '-233' (0xffffff17).
    The title is 'SC_ERR_PATH_BROKEN'.

    The explanation is:
    The JTAG IR and DR scan-paths cannot circulate bits, they may be broken.
    An attempt to scan the JTAG scan-path has failed.
    The target's JTAG scan-path appears to be broken
    with a stuck-at-ones or stuck-at-zero fault.

  • In reply to odors:

    is this a custom board or a TI evaluation module?  The issue with the reference post was with the reset RC constant needing more time to enable the SOP latch at the right state.

    BR,

    Charles O

     

  • In reply to Charles Oladimeji:

    Hi,

    That  is a our board not TI's one.

    However,  the RC value of our board is the same like reference circuit.

    I really want to know what I have to check or next step to resolve problem.

    Best Regards,

     

  • In reply to odors:

    Hi,

    Using an oscilloscope, can you confirm that SOP0, 1 and 2 gets to 3V3 before the reset line crosses 1.5V?

    Can you also send a snapshot of the CCS debug interface showing where the device is getting stuck?

    Regards,

    Charles O

     

  • In reply to Charles Oladimeji:

    Hi,

    What does that mean the reset line?

    Do you want to know settling time to get to 3.3V?

    Best Regards,

  • In reply to odors:

    Hi,

    There should be an RC timer connected to the IWR6843 IC. The SOP pins should settle at 3.3V before the reset RC voltage rises to 1.5V.

    Can you confirm that this is the case?

    Regards,

    Charles O

     

  • In reply to Charles Oladimeji:

    Hi,


    I have tested SOP settle time between Ref. B'd of TI and our customer B'd.


    But, I can't find the difference between them. (The rising time is so fast, I can't distinguish each of them.)


    The fundamental problem is that there is no oscillation of a crystal output.

    I 'd like to know whether this has somthing to do with settling time of SOP pins.

    Please advice to me to find the reason of this problem.


    Best Regards,

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.