Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: Clause 51 (XSBI) questions : PMA_TXSRC_CLK

Hello Henning,

Agreed on the need to use  the PMA_TXCLK_SRC as a reference for
the PCS. In that light I would modify (not REMOVE) section 51.3.1 line46 to 
emphasize this need. new line to read

"The PMA_TXCLK_SRC is used by the PCS to derive the PMA_TX_CLK." 

This comment was  previously mentioned on page 202 line 46/47 but I think
it is very worthwhile to repeat it again here.

We can take the details of the wording off line if the concept is agreed. 


In a message dated 10/13/00 8:18:09 AM Pacific Daylight Time, 
henning.lysdal@xxxxxxxxx writes:

>  Justin, Erik,
>  Much as we agree on must issues Justin, I have to disagree when you state
>  that "It is not required that one uses the PMA_TXCLK_SRC".
>  It is not required that the PCS use a specific edge of the PMA_TXCLK_SRC.
>  However, PMA_TXCLK_SRC is the primary clock source for the PCS (remember
>  that the reference clock for the PMA is not specified). Furthermore, if the
>  PCS does not use the PMA_TXCLK_SRC, you open the loop thereby ruling out a
>  PLL based timing control.
>  Regards,
>  Henning

Justin Chang
Quake Technologies, Inc.
50 Airport Parkway, San Jose, CA. 95110
Tel: 408-437-7723       email: justin@xxxxxxxxxxxxx
Fax: 408-437-4923       internet: