TLK10034: use USB-2-MDIO to communicate with TLK10034; Tool detects all PHY IDs and returns FFFF

Duo Xu

Prodigy 10 points

Part Number: TLK10034
Other Parts Discussed in Thread: MSP430F5529

I am trying to use USB-2MDIO GUI to talk to TLK10034. The LaunchPad I use is MSP430F5529.

I connect external 1.8V to the MSP430F5529.

When I try to read or write through GUI, it always returns FFFF.

Plus, when I run the "Find PHY ID" command, it tells that it found on all IDs a working PHY, which is not the case.

Also, one strange thing is that when it runs read/white function and FInd PHY ID, the voltage increases from 1.8V to 2.2V, which not meet the voltage spec for TLK10034(1.8V)

Any help will be appreciated.

Thank you very much!

Duo

11 months ago

0 Evan Mayhew 11 months ago

TI__Genius 14792 points

Hi Duo,

Can you share a schematic showing the TLK <-> MSP connections, and a waveform of the MDC/MDIO transaction during your R/W attempts?

Thank you,

Evan

0 Duo Xu 11 months ago

Prodigy 10 points

Hi Evan, thanks for the reply.

Here is the setup:

Remove 3V3, SBW TDIO and SBW TCK jumper in order to feed 1.8V power on launchpad side.
Use p4.1 and p4.2 pin for MDIO communication bus.
Connect external 1.8V power and Ground at J10.

Here is the plot of read: https://imgur.com/a/uEf3ohT

Here is the plot of write: https://imgur.com/a/cig7Imc

Since I found when it is doing read/white, the voltage jump from 1.8V to 2.2V~, but when I feed a fix 1.8V from the voltage regulator from our board, the read/write won't work. Any way to make it work under 1.8V?

0 Evan Mayhew 11 months ago in reply to Duo Xu

TI__Genius 14792 points

Hi Duo,

I don't expect this to work with a fixed 1.8V fed into J10 - the minimum logic domain in this case is ≈2.2V.

This is a quirk of the MSP devkit design. Aside from feeding a higher voltage on this pin, there is no workaround.

Thank you,

Evan

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TLK10034: use USB-2-MDIO to communicate with TLK10034; Tool detects all PHY IDs and returns FFFF