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TPS65982-EVM: TPS65982-EVM DR_Swap Sequence lead to unexpected process

Prodigy 50 points

Replies: 7

Views: 199

art Number: TPS65982-EVM


I make the TPS65982-EVM as a DRP and connected with adapters, so the TPS65982-EVM must be a sink on my test.

I saw TPS65982-EVM sent the DR_Swap and lead to unexpected Soft reset or Hard reset sequence after connecting with adapter. 

The process is just like following figures.

Figure 1 DR_Swap lead to Hardreset Sequence

Figure 1 DR_Swap lead to Softreset Sequence

This issue is always appeared at DR_Swap sequence, but it is not easy to be reappeared.

Is it a known issue?

  • Hello Otto,

    I've assigned your question to the respected to expert. He is currently out of office on business travel, so expect a delay in his response.


    Adam McGaffin

  • In reply to Adam Mc Gaffin:

    HI Otto,

    Can you please post the firmware version and Application Config GUI version you are using? Have you made any changes to the default project, if yes, please post the pjt file you are using.

    Do you only see this issue with the particular adapter? Which one is causing problems in the test?



  • In reply to Scott T:

    Hello Scott

    The firmware is "tps65981_2_3b_6_v00066.bin".

    I only made one change to Tx sink cap(0x33) that is just like following figure.

    I have two adapters both can make this issue be observed, and these two are individually collocated with two different model of PD controller.

    By the way, I also made the source reply an accept later in response to the DR_Swap, and the unexpected Soft reset and Hard reset sequence seemed to cannot be observed again.

    But, there are still occasionally an extra DR_Swap message to be sent  from TPS65982-EVM before source reply accept . It is just like following figure.

    So, I think this issue is maybe related to what the time source reply an accept in response to DR_Swap.

    If you have more appropriate firmware, please provide it to me and I will do the test again. 

    Or you need more information please let me know.

    Thanks you very much.

  • In reply to Otto Yang:

    Hi Otto,

    Can you download the most recent TPS659xx Configuration tool and update the device firmware?




  • In reply to Scott T:

    Hi Scott

    The previous issue is solved after upgrading Tps65982-EVM with the V0001.12.09 firmware via the most recent TPS659xx Configuration tool.

    But another issue was observed with V0001.12.09 firmware that showed as bellow.


    It's still not easy to be reappeared.

    The following file is the project that I used in my test.

    0825 issue.zip

    By the way, this new issue is not  only observed with particular adapter.

    Could you help us to fix this new issue, Please!

    Thanks you very much.

  • In reply to Otto Yang:

    Hi Otto,

    What I observe in each case is that the Sink:UFP fails to send GoodCRC in response to a message. The Source:DFP makes 3 attempts, then attempts Soft_Reset and finally Hard_Reset. After Hard_Reset it appears that the partners resume PD communication. Is there an issue with PD communication after the Hard Reset?

    From the trace, there is not necessarily an issue. We need more information to understand what is going on. Have you checked a scope trace of Vbus and CC to look for an attempt to send GoodCRC?



  • In reply to Scott T:

    Hi Scott

    It  is OK with PD communication after the Hard Reset.

    In my opinion, there is an issue with Sink fails to send GoodCRC in response to the message(Accept or PS_RDY) because of it lead to the Hard Reset and output voltage hiccup. 

    However, I am currently handling another project, so I will check the scope trace of the CC waveform if I am free.