Xilinx Answer #581 : PROTEL 2.2: Use of carry logic causes XNFPREP ERROR 3626

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PROTEL 2.2: Use of carry logic causes XNFPREP ERROR 3626

Record #581
Problem Title:
PROTEL 2.2: Use of carry logic causes XNFPREP ERROR 3626

Problem Description:

Solution 1:

PROGRAM: Protel

VERSION: 2.2

PLATFORM(s): PC

SHORT DESCRIPTION:

XNFPREP error 3626 issued on designs containing xc4000 carry logic symbols.

ERROR MESSAGE:

     XNFPREP Errors
     --------------
     XNFPREP: ERROR 3626:
       The carry mode symbol `U1/U69' (type = CY4_18, C1 signal =
       U1/N00057) does not have a CYMODE parameter.

       This is probably caused by an error in the library or the translator
       that generated the XNF file. Please contact the vendor that provided
       the XNF interface.

LONG DESCRIPTION:


PROBLEM:

While running XNFPREP on any Protel designs that contain any CY4_xx symbols,
this error is reported back. This includes user created carry logic and
Protel supplied macros that use carry logic.

CAUSE:

Current Protel Libraries don't have the attribute CYMODE=<cymode> on the
CY4_xx symbols. XNFPREP requires that this attribute be attached.

SOLUTION:

Add the attribute CYMODE=<cymode> to the CY4_xx symbols in the 4k library.
For example CY4_18 should have CYMODE=INC-FG-CI attribute.

End of Record #581 - Last Modified: 03/07/97 08:20

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