Synthesizing fixed_pkg in ISE 9.2

Aug 08, 2007 10 Replies

Hi,



I'm trying to synthesize a design with the fixed_pkg package in Xilinx ISE 9.2. I'm using the version adapted for Xilinx from

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Compilation works fine, but after that I get the following, not exactly helpful error message:



=========================================================================



  • Design Hierarchy Analysis
  • ========================================================================= ERROR:Xst:2683 - Unexpected error found while building hierarchy.
This happens both with the synthesis test from the website above and with my own trivial example (attached at the end of the post). You can get the complete test project from http://www.mikrocontroller.net/attachment/25445/fixpt-test.zip. Has anyone found a workaround to use fixed_pkg with ISE? Thanks, Andreas Attachment: architecture rtl of top is signal x, y : sfixed (3 downto -3); begin x

I haven't even tried since the author of the package reported:

"After fixing everything, it gave me the error:

INTERNAL_ERROR:Xst:cmain.c:3111:1.8.6.1 - To resolve this error, please consult the Answers Database and other online resources at

formatting link

This is a "use at your own risk" one I guess. I would recommend Synplicity, which seems to work much better."

I am the author.

Xilinx said that they were going to fix this in 9.3. I have not had a chance to check it out yet, but I would try that first.

Thanks for the info. 9.3 isn't released yet, do you have any idea when it will be?

Andreas

I'd use Synplicity. I've been using 8.803 with these packages.

There is no ISE 9.3. Maybe they meant ISE 9.2.03i (service pack 3) which is scheduled to release September 14.

Steve

There is a nice fixed-point package from Doulos which I successfully used in the past. Look it up on their website.

Manny,

thanks for the free publicity, but please DON'T use it... there are a few rather significant bugs with signed arithmetic, and it's not as complete as the IEEE packages.

I wish I had worked more closely with David Bishop on this, because I believe my (Doulos) package has a few features that are worth having; but it's far too late now, the IEEE package is far better developed, and it has a test suite - something I should have done in the first place, but never had time to do.

I PROMISE to take the packages down from our website before the end of the week, and instead leave a pointer to the IEEE set!

cheers

Jonathan Bromley, Consultant DOULOS - Developing Design Know-how VHDL * Verilog * SystemC * e * Perl * Tcl/Tk * Project Services Doulos Ltd., 22 Market Place, Ringwood, BH24 1AW, UK jonathan.bromley@MYCOMPANY.com http://www.MYCOMPANY.com The contents of this message may contain personal views which are not the views of Doulos Ltd., unless specifically stated.

Hello,

Regardless, I got this error while synthesizing a Verilog project. The problem was that I adopted a project from ISE 7.1.04. After starting a fresh project on ISE 9.2, handpicking the HDL files and UCFs (and so on) the synthesis went smoothly.

Maybe this will do the trick for you too.

Eli

I had the problem with a fresh 9.2 VHDL-only project. Which version of fixed_pkg did you use? The Xilinx-adapted from

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or the original package from the VHDL200x website?

Thanks, Andreas

I installed the ISE service pack 2, and the error message became more specific: ERROR:Xst:2744 - "C:/Dokumente und Einstellungen/A/Eigene Dateien/FPGA/ fixpt-test/vhdl200x/fixed_pkg_c.vhdl" line 1026: alias of a function is not supported. ERROR:Xst:2683 - Unexpected error found while building hierarchy.

So I commented out the function aliases cleaned up the project files (otherwise I would get "ERROR:HDLParsers:333 - Binary file "xst/ ieee_proposed/sub00/vhpl02" is corrupted. Recompile unit fixed_pkg.fixed_pkg."), and everything compiles just fine.

Only division does not work: ERROR:Xst:769 - "C:/Dokumente und Einstellungen/A/Eigene Dateien/FPGA/ fixpt-test/vhdl200x/fixed_pkg_c.vhdl" line 2599: Operator must have constant operands or first operand must be power of 2

Andreas

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