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AR# 4766

F1.5F2.1i ABEL - Abl2edif creates an incorrect netlist when the underscore character is used at the end of a signal name: give based:24 error in translate


Keywords: F1.5/F2.1i, ABEL, netlist, underscore, invert, negative, _, edif2ngd, duplicate instance

Urgency: Standard

General Description:
Translate (edif2ngd) give the following warning when processing a design created in ABEL:

ERROR:based:24 - On or above line <xx> in file
"<project directory>/<project>.edn":
Duplicate instance, "FF_xxxxxx", in cell "<abel file name>". This likely means that
the EDIF netlist was improperly written. Please contact the vendor of the
program that produced this EDIF file.


This Duplicate Instance error is caused by assigning two signals the
same name with an underscore at the end of one signal name. This is
often done to show inversion.

Example: mysig and mysig_

The mysig_ is not being differentiated properly because abl2edif adds an
'_' to most signal names. Therefore mysig also becomes mysig_ .

One of the names needs to be changed in the .ABL code

Instead of:

mysig PIN;
mysig_ PIN ISTYPE 'reg';

mysig_ = !mysig;

Do this:


mysig PIN;
mysig_N PIN ISTYPE 'reg';

mysig_N = !mysig;
AR# 4766
Date Created 10/07/1998
Last Updated 06/10/2002
Status Archive
Type General Article