Answers Database


M1: NOCLIP, S, NOMERGE, X and KEEP properties


Record #2501

Product Family: Software

Product Line: FPGA Implementation

Product Part: map

Problem Title:
M1: NOCLIP, S, NOMERGE, X and KEEP properties


Problem Description:
Urgency: hot

General Description:
In M1, there may be some confusion on these properties:
NOCLIP, S, NOMERGE, X and KEEP. These are different ways
of specifying that signals not be trimmed or that they not
be merged into CLB function generators.


Solution 1:


The chart below explains the relationship between
these property names:

XACT	      Foundry	     M1        function
-----------   -----------   ---------  -----------------------
S (savesig)   NOCLIP	    S	       prevents loadless and
				       sourceless nets from
				       being trimmed; NOTE:
				       does not prevent
				       trimming of
				       nets attached to
				       disabled logic.

X NOMERGE KEEP prevents a net from
                            being merged into a CLB




End of Record #2501 - Last Modified: 07/23/97 20:37

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