TPS65988: How do we judge if the FW issue depends on TPS65988 or Intel TBT?

Hi Alan,

Do you test your new project on the customer's hardware or you test it on an EVM?

If you're testing your new firmware on customer's board and it's working then you need to check the firware configuration settings.

Do let me know if you have further questions.

Thanks,
Rahul

Hi Alan,

Any update on this?

Thanks,
Rahul

Hi Rahul ,

Sorry for reply late and thank you for your help.

The usb2.0/3.0 on customer's board is working, but TBT function is still failure with external screen connected through  type C. It seems HPD signal from tps65988 does not pass to TBT when cable plug in, what is the correct  settings related HPD functions in PD firmware ?

Alan

Hi Allan,

TPS65988 doesn't generate HPD signal, it comes as a message from the port partner and 88 gives this signal upon receiving this message.

Can you share the PD logs for me to analyze?

Thanks,
Rahul

Hi Rahul ,

There is pin30 and pin31 for HPD1 and HPD2 on TPS65988 which connect to Intel TBT port A HPD and port B HPD.

I don't have tools to dump out the Log (What kind of tool can output LOG?), I attached.pjt file If this helps to analyze the problem.TPS65988DH_F707_10_03_testing_FM_ver4.pjt

Hi Alan,

What I meant is, that these pins 30 & 31 toggles when they get a HPD message from the port partner. These pins will not toggle unless there's a HPD message on the Type-C bus.

You can use Power delivery analyzer from total phase (www.totalphase.com/.../), or Lecroy T2C (teledynelecroy.com/.../mercury-t2c-t2p).

Thanks,
Rahul

Hi Alan,

Any update on this?

Thanks,
Rahul