Answers Database

M1 : How to specify SAVESIG ("S"), "KEEP", or "X" constraints on nets using a UCF file.


Record #2570

Product Family:  Software

Product Line:  Merged Core

Problem Title:
M1 : How to specify SAVESIG ("S"), "KEEP", or "X" constraints on nets
using a UCF file.



Problem Description:
Keywords:  savesig, S, X, Keep, constraint, property

Urgency: standard

General Description:
In the M1 release it is possible to specify the SAVESIG ("S"),
"KEEP", and "X" constraints on nets using the .UCF file.


Solution 1:

The syntax is documented in the Xilinx Libraries Guide
in the UCF syntax section of the  "Attributes and Carry Logic"
chapter.

Syntax:  net "<net_name>"  <net_property>;

Example:  net "mynet" "S";



End of Record #2570