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NGDBUILD: "logical block" of type 'DFFRSE' is unexpanded with a Synplify netlist


Record #3611

Product Family: Software

Product Line: Synplicity

Product Part: Synplify

Product Version: 3.0

Problem Title:
NGDBUILD: "logical block" of type 'DFFRSE' is unexpanded with a Synplify netlist


Problem Description:
Urgency: Standard

Problem description: Ngdbuild issues a warning on a behaviorally
described asynchronous set/reset regesiter with clock enable

warning basnu:93-logical block 'rebk1' of type 'DFFRSE' is unexpanded.


Solution 1:

Synplify will infer a DFFRSE to describe an asynchronous set/reset
register with clock enable. However, the DFFRSE is not a valid
Xilinx primitive. Earier versions of Synplify have this problem.
Version 3.0c1 and above correct the problem by inferring a DFFRS.

The generic DFFRSE is no longer generated for 9500 series devices.

The DFFRS is also not a Xilinx primitive. See (Xilinx Solution 3486)
However, Synplicity provides the XNF netlist of the DFFRS. Make sure
you either source the directory with '-sd' option in Ngdbuild, or copy
the appropriate XNF file to your project directory so M1 could see the
files. These XNF netlists are located in the C:\synplcty\lib\xilinx
directory on the PC, and $SYNPLICITY/lib/xilinx on the WS.

You will need to upgrade to a more recent version of Synplify from
Synplicity:

http://www.synplicity.com/support.htmlInternet Link




End of Record #3611 - Last Modified: 01/05/99 15:49

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