DP83822I: How to generate random packets from Link-partner for 10Base-Te compliance test.

Nikhil-san,

Thank you for your information.

How about DP83822 setting to generate PRBS data?   For generating PRBS data for DP883822, Set "PRBS Generation Enable" bit on 0x0016 BIST control resister.  Is it correct?  Please let us know.

Thanks and best regards,
M.HATTORI

Nikhil-san,

I have one more question.   My customer wants to generate PRBS data for 16ms only.  Do you have any solution?  Please advise us.

Thanks and best regards,
M.HATTORI

Hi HATTORI-san,

This is a very tight window to generate PRBS data. The PRBS feature is usually used for general debug purposes, we have not intended this feature to be enabled/disabled in such a short time period.

What is the current method customer is using to program PHY registers? If a processor is connected and can be programmed to adjust the PRBS registers within this interval that may be an option.  

What is driving customer need for enabling PRBS packets for such a short time period?

Thank you,

Nikhil Menon

All information in this correspondence and in any related correspondence is provided “as is” and “with all faults”, and it is subject to TI’s Important Notice (http://www.ti.com/corp/docs/legal/important-notice.shtml).

Nikhil-san,

According to "10 Base-T Difference Voltage Test" on Tektronix manual, period of Random packet output is less than 16ms, because this test may be failed on long random packet period.

Anyway, I have one question.  On this test, Tektronix recommends the following both cases.

1. Link-partner outputs random packet.
2. DUT(DP83867) outputs random packet.

But According to the application note [snla239a], TI suggests link-partner only.  Does TI also recommend DUT (DP83867) outputs random packet?   Please advise us.

Thanks and best regards,
M.HATTORI

Hi HATTORI-san,

We are looking into this issue and will provide additional feedback tomorrow.

Thank you,

Nikhil

All information in this correspondence and in any related correspondence is provided “as is” and “with all faults”, and it is subject to TI’s Important Notice (http://www.ti.com/corp/docs/legal/important-notice.shtml).

Hi HATTORI-san,

Can you provide the document and explicit requirement for the 16 ms signal length? We are not familiar with this requirement. 

Thank you,

Nikhil

Hi, Nikhil-san,

At first, could you please let us know the following?

Does TI also recommend DUT (DP83867) outputs random packet without link-partner?

Thanks and best regards,
M.HATTORI.

Hi HATTORI-san,

Per SNLA239, for the 10Base-Te testing, TI recommends using link partner for packet generation.

Thank you,

Nikhil

All information in this correspondence and in any related correspondence is provided “as is” and “with all faults”, and it is subject to TI’s Important Notice (http://www.ti.com/corp/docs/legal/important-notice.shtml).