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AR# 4995

4.1i Licensing - When does FPGA Express check out a floating license?


Keywords: 1.5, 2.1i, 3.1i, 4.1i, Foundation, FPGA Express, security, license, floating

Urgency: Standard

General Description:
I cannot obtain a license for FPGA Express, even though there are not any users performing synthesis.
NOTE: This issue applies ONLY if you use floating licenses. If you use node-locked licenses, you should not experience this problem.


FPGA Express licenses are checked out in the following instances:

- When you open up a top-level HDL project, the following licenses are checked out:

- When you want to synthesize, and another license is checked out, the following license is used:
fpga-express-XXXX-optimizer (enter your target family for XXXX)

(When synthesis is completed, the optimizer license is checked back in.)

- When you open a top-level schematic project, NO license is checked out. A license is checked out only during synthesis (create/update macro). However, at that time, all three licenses are checked out:

At the end of synthesis, all three licenses are immediately checked back in.

To summarize, if you open a top-level HDL project, you are "reserving" a license that only you can use for synthesis. You should always close top-level HDL projects when the projects are not in use.
AR# 4995
Date Created 11/06/1998
Last Updated 08/11/2003
Status Archive
Type General Article