Answers Database
NGDAnno: What's GSUH
Record #6893
Product Family: Software
Product Line: FPGA Implementation
Product Part: ngdanno
Product Version: 2.1i
Problem Title:
NGDAnno: What's GSUH
Problem Description:
Urgency: Standard
Problem Description:
What's the GSUH check in NGDAnno2.1i.
Solution 1:
In addition to the setup and hold checks already performed during back annotation, NGDAnno
runs a Guaranteed Setup and Hold Check(GSUH) on IOB registers for each data pin and clock
pin that's added. The GSUH values calculated are a conservative measure of device performance,
which match closely with the values represented in the Programmable Logic Data Book.
The GSUH_setup_value is measured with the fastest clock path and slowest data path.
The GSUH_hold_value is measured with the slowest clock path and fastest data path.
Tgsu = Tdmax - Tckmin + Tsu
Tgh = Tckmax - Tdmin +Th
The new external GSUH check allows you to see a setup violation at the device pins
by incorporating clock and data delays to the IOB register into a setup check at the
edge of the device.
Note: Guaranteed Setup and Hold Checks may not be supported for some devices.
For more information, please refer to NGDAnno chapter of
the Development System Reference Guide
End of Record #6893 - Last Modified: 01/14/00 14:57 |
