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XNFMERGE 5.0: About ERROR 221


Record #353

Problem Title:
XNFMERGE 5.0: About ERROR 221


Problem Description:




Solution 1:




With the XACT 5 release, it is not legal to have a hierarchical symbol with
an underlying schematic that contains a different symbol having the same
name. For example, the schematic for a symbol called FT should not contain
the Xilinx library part FT. If this is done, the following error would be
issued by xnfmerge:

     Read file ft.xnf
ERROR 221: Filename ft.xnf called recursively.
      Can't accept recursive designs

The simple solution is just to be sure not to name a user-created symbol with
the same name as one of the Xilinx library parts. However, Mentor users may
be using one of the Xilinx-supplied shadow libraries. Every part in the library has a recursively-named structure. Fortunately, there is a way to
circumvent this problem as well. If you are using a design done with the
Mentor shadow library, run edif2xnf manually without the -n (do not flatten
design) option. This option is always used by men2xnf8. When edif2xnf
is run without the -n option, it flattens the design into a single xnf file,
which resolves the recursive-naming problem before xnfmerge is ever run, as
the symbols in the netlist then have hierarchical names (in the above example,
we would have FT and FT/FT)





End of Record #353 - Last Modified: 04/01/97 07:42

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