UPGRADE YOUR BROWSER

We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

AR# 14606

Virtex-II Pro RocketIO - How do I perform clock correction on a multiple comma sequence (rather than a single comma)?

Description

The dedicated hardware for comma alignment will align only when a single comma is used. How do I set up the transceiver so that it aligns on a particular series of commas?

Solution

Here is a simple example scheme: connect RXCOMMADET to ENPCOMMAALIGN and ENMCOMMAALIGN.  

 

In this case, realignment will occur only in the presence of a burst of commas, with the first comma causing ENPCOMMAALIGN and ENMCOMMAALIGN to be asserted, and subsequent commas causing realignment. A single comma should not cause realignment in this case. 

 

Some experimentation may be needed to determine how long a burst of commas must be in order for realignment to occur reliably, but it is probable that four or more commas will be required.

AR# 14606
Date Created 08/29/2007
Last Updated 05/14/2014
Status Archive
Type General Article