TMS570LC4357: TMS5770HDK with external PHY

Hi Abhi,

In below FAQ, you can find several examples related to LwIP in TMS570LC4357 HDK board

(+) [FAQ] TMS570LC4357: Examples and Demos available for Hercules Controllers (E.g. TMS570x, RM57x and RM46x etc) - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

And all these examples are built using DP83640 as PHY, so the pinmux settings also according to the DP83640. My suggestion would be comparing the pin configuration of this PHY with DP83811, if they are pin to pin compatible then we no need to do any other pin mux modifications. If they have any pin differences then we can do the corresponding modifications.

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Thanks & regards,
Jagadish.

Hi Jagadish,

Thanks for the prompt reply.

I am able to get IP with internal PHY I have used LWIP example of this.

When I try the same example with external PHY using dp83tc811, software is not able to communicate with the device. 

We have created harness for MII and MDIO lines to the external PHY, all looks good but the software is unable to detect the PHY. Hence the question regarding Mux.

I have also included wiring diagram with the external PHY.

Regards,

Abhi

The wiring picture diagram may be in png format so can't be able to see the pin names properly.

Can you please re-upload the diagram.

HDK_PHY_Connection Diagram.pdf

Attached PDF of wiring diagram

One more thing, I have also modified PHY board to MII interface. By default it came with RMII, we followed the datasheet and modified it to MII mode.

Hi Jagadish,

Do I have any update on this?

Regards,

Abhi

Hi Abhi,

Apologies for the delay, today i got a chance to verify your connections.

I want to know the following things:

Did you make the connections in green highlighted boxes? looks like they are DNP (Do Not Place) that means there is no connections between TX_P and TX3_P, TX_N and TX3_N similarly for RX pins. So, we should need to make sure to connect these pins.

And also, it would better to remove the capacitors (red highlighted box) maybe they are placed for RMII mode. If we are going for MII mode may be these capacitors are not required.

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Thanks & regards,
Jagadish.

Hi Jagadish,

Thanks for the reply, I can confirm following on the PHY board.

For MII mode, we have done the changes you have mentioned. In DNP (R18, R19, R21 and R22), have a zero ohm resistor populated.

We have also removed C12, C14, C 15 and C16.

With regards to software, do I need to modify Mux settings for external PHY. Or existing Mux settings for internal PHY is okay?

I have used TI LWIP example for this project.

Do you have any example with external PHY which I can try?

Regards,

Abhi

Hi Abhi,

If you are using HDK demo's then there won't be any further mux settings required. Make sure you are using HDK example instead of Launchpad.

Also refer my HDK example projects below, here i gave detailed procedure in step by step on how to execute the demo projects on HDK boards.

(+) [FAQ] TMS570LC4357: Examples and Demos available for Hercules Controllers (E.g. TMS570x, RM57x and RM46x etc) - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

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Thanks & regards,
Jagadish.

Hi Jagadish,

Thanks for the reply, yes I am using HDK demo and I have followed your instructions.

I will repeat all that again with new PHY board and come back to you next week.

Is it possible to provide example with external TI PHY we are using, this will eliminate wiring issues?

If it doesn't work with your example then we can look into our wiring harness.

Regards,

Abhi

Abhi said:

I will repeat all that again with new PHY board and come back to you next week.

Sure Abhi.

Abhi said:

Is it possible to provide example with external TI PHY we are using, this will eliminate wiring issues?

We don't have any examples with external PHY that you are using.

That's really helpful, that's for your support.

Regards,

Abhi 

Thanks (Thats typo)