DP83867IS: how to choose the RGMII TX CLOCK SKEW and RGMII RX CLOCK SKEW

Tess Chen

Part Number: DP83867IS

Dear team,

From the table 6 4-Level Strap Pins of datasheet, RGMII RX CLOCK SKEW and RGMII TX CLOCK SKEW are configured with different mode. And with specified mode, result with different delays in table and 9. I would like to know how to determine the RGMII TX CLOCK SKEW and RGMII RX CLOCK SKEW time delay from CPU to PHY in table 8 and 9. What are the related factors which I need consider? Thanks.

over 4 years ago

0 Nikhil Menon over 4 years ago

TI__Genius 11725 points

Hi Tess,

We are looking into your questions and will provide additional feedback by Thursday latest.

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).

0 Nikhil Menon over 4 years ago in reply to Nikhil Menon

TI__Genius 11725 points

Hi Tess,

Table 8 and Table 9 show the skew values between the data and the respective clock (for example, the delay between RX_CLK and RX_D[3:0]). If you wish to measure the delay between the PHY and CPU, one suggestion I have is to measure the signal very close to the PHY and very close to the CPU and measure the delay between the signals.

Please let me know if you have any further questions. Else, I will be closing this thread.

Thank you,

Nikhil

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DP83867IS: how to choose the RGMII TX CLOCK SKEW and RGMII RX CLOCK SKEW