LVDS SERDES Transmitter / Receiver IP Cores User Guide

ID 683062
Date 12/15/2017
Document Table of Contents Obtaining the RSKM Report

For LVDS receivers, the Intel® Quartus® Prime software provides the RSKM report showing SW, TUI or LVDS period, and RSKM values for non-DPA mode. You can generate the RSKM report by executing the report_rskm command in the TimeQuest Timing Analyzer.

To obtain the RSKM report, follow these steps:

  1. In the Intel® Quartus® Prime software, under the Tools menu, click TimeQuest Timing Analyzer.
  2. From the TimeQuest Timing Analyzer, under Reports, select Device Specific and click Report RSKM.

In the TimeQuest timing analyzer tool, the report_TCCS and report_rskm commands are not available when you are using SERDES in LEs. The commands are only available for transmitter and receiver with dedicated SERDES.

The Intel® Quartus® Prime software automatically places the SERDES logic at the best location to meet timing requirements. Therefore, you are not required to perform placement constraints on the ALTLVDS IP core logic. However, you are recommended to perform timing budget evaluation for the overall LVDS interface in your system to ensure the sampling window specifications are met.

The LVDS transmitter and receiver functions with the ALTLVDS IP core are characterized and guaranteed to function correctly within the LVDS system specification (meeting TCCS and SW parameters). Therefore, timing constraints are not required for the SERDES logic using the ALTLVDS IP core. However, if the timing result does not fulfill the requirement or the design needs to be fine-tuned to improve the margin, timing constraints may be necessary.

The setup time (TSU) and hold time (TH) for the LVDS channels as reported in the Intel® Quartus® Prime timing report are based on the compiled design and served as a timing reference. You must not use these parameters in the timing report for the sampling window estimation. For sampling window specification, refer to the device datasheet for more information.