TPS65982: Single-Wire Debugger Interface

The SWD interface is typically reserved for internal debug. If you would like to communicate with the PD controller, I would recommend using the I2C interface. There is plenty of documentation readily available on how to interact with the PD controller using the I2C channel 

Thank you for your response.

I am aware of the i2c interface, but still would like to use the available and user exposed SWD, even if its use is "atypical". No publicaly available documentation mentions that SWD is an internal-only interface, quite the opposite (see the excerpt in the head post).

My question is not when or wheter to use the SWD, but how.

Yes I understand your request. What I am saying is that you will have a difficult time implementing this functionality since there is no documentation explaining how to use it. The I2C interface is well documented and should make your design implementation much simpler. 

Lack of documentation is not the reason to abadon a promised interface. It is a reason to release missing documentation.

Is there a specific reason why you are wanting to use SWD as opposed to I2C? They both require two wires, and you actually get more functionality from an I2C interface with the use if the IRQ line. 

SWD is muxed out in debug accessory mode, i2c is not.

Here is an excerpt from a previous E2E thread (link below)

The muxing of SWD onto SBU pins is a TI internal FW debug feature, but does exist in firmware 1.12.07 as you suggest. We do not recommend using this mode, which was put into the device for internal development and debugging purposes, but if you do use the mode we are unable to alter its functionality. 

https://e2e.ti.com/support/interface/f/138/t/701315#pi320995filter=all&pi320995scroll=false 

The muxing functionality is not recommend, so if that is your reason for picking the SWD communication over I2C, then I would recommend using I2C since I2C gives you more control and features such as the IRQ functionality. 

Thank you again for your recommendation.

Once again, though, I am not looking for any further recommendations against (or even for) using SWD interface. I fully understand that it is "atypical" and "not recommended." What I AM looking for is documentation on HOW to use it, especially since the interface is stated to be available and accessible (even if "not recommended," which is by the way not mentioned in the oficial documentation).

There is currently no document outlining how to use the SWD interface excluding what is already mentioned in the datasheet. Figure 9 in the datasheet shows the messaging sequence for the SWD interface, highlighting the timing variables described in table 7.25. 

Refer to the host interface technical reference manual to know what registers and values to write/read

https://www.ti.com/lit/ug/slvuan1a/slvuan1a.pdf?ts=1591126463876

What is the cpu architecture of the digital core, if any?