AR# 8923: Virtex-E 2.1i PAR: pad report does not include the pads for LVDS/LVPECL N side inputs
Virtex-E 2.1i PAR: pad report does not include the pads for LVDS/LVPECL N side inputs
Keywords: Virtex, Virtex-E, LVDS, PAR
Pad report from par doesn't have any of the N-side input pads listed. But they are used in the hardware. Some of the board level simulation tools may need to have the pad report that has all the pin information, including the N-side input pads. How to create a pad report that includes the N-side input pads?
Designing with LVDS/LVPECL requires you to lock down all the IO pins before running the implementation process. Therefore, The pad report created will always have the same pin locations. To create a report with the N-side inputs, users must add them in the pad report manually. Since all the pins have the same location, the pad report from each implemenation will always be the same, which means the users only need to add the N-side pads in the pad report once, save it in a different area, and use it over and over again.
Here is an example on how to add the N-side input pins in the pad report.
the differential pair has the name, data_p for the P-side, and data_n for the N-side, the pad report only shows the P-side as:
data_p INPUT A20
To add the N-side, add the additional line in the pad report: