Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!pacbell!att!shuxd!attdso!rolls!mtuxo!lzfmd!rtw
From: rtw@lzfmd.att.com (R. T. Wurth)
Newsgroups: comp.sys.apollo
Subject: Re: Mystery Error (unable to unwind stack)
Summary: Mentor Graphics tools:  Bad JEDEC format for PLDs?
Message-ID: <961@lzfmd.att.com>
Date: 27 Apr 89 12:21:16 GMT
References: <42d82721.8b6c@apollo.COM> <15546@elroy.Jpl.Nasa.Gov> <633@idacom.UUCP>
Organization: AT&T Bell Labs
Lines: 47

In article <633@idacom.UUCP>, danny@idacom.UUCP (Danny Wilson) writes:
> In article <15546@elroy.Jpl.Nasa.Gov>, dave@jplopto.uucp (Dave Hayes) writes:
> > 
> > That would explain the errors that my users keep getting, tho. We are 
> > using Mentor Graphics tools, and their EXPAND tool is the only one that they
> > see this error in. I guess I should take that up with them.
> 
> A stack frame error *may* happen if the sheets that are being compiled
> into the design file have buggy BLM's (Behavior language models).
> That is, if your people are writing their own BLM code and it is
> not quite up to snuff. Another possibility is if you use third-party
> models (like Logic Automation or Quadtree) and there are bugs in them.
> 
> I have *never* seen a stack frame error during Expand in over 
> 5 years of using expand... I would expect it more during a simulation
> run with QuickSim.
> Danny Wilson
 ...
> IDACOM Electronics		danny@idacom.uucp
> Edmonton, Alberta		alberta!idacom!danny
> C A N A D A

One particularly bad problem that burns us every time is that the
supplied models for programmable logic (PALs, (PAL is a trademark of
MMI/AMD) in particular) blow up when confronted with "skinny" JEDEC
formatted fuse information.  "Fat JEDEC" explicitly specifies every
fuse.  "Skinny JEDEC" uses a special operator at the start of the
JEDEC file to specify a default state and then includes only those
lines of a "fat JEDEC" file containing at least one fuse not in the
default state.

The versions of PALASM (PALASM is a trademark of MMI/AMD) that we
use (on a PC and on our VAX host running the UNIX\*(Rg System V
operating system (UNIX is a trademark of AT&T)) all produce skinny
JEDEC.  Someone hacked up the PALASM source code from a very old
PALASM release to produce "fat" JEDEC on our workstations, but it is a
very old version that doesn't support all devices.  Our current
workaround is to download the "skinny" JEDEC to our programmer, and
then upload it from the programmer, since the programmer (DATA I/O)
alwasy puts out "fat" JEDEC.

I don't recall which tool blows up, but when it does, it produce no
error message, it just faults back to the shell.

	Rich Wurth / lzfmd!rtw OR rtw@lzfmd.ATT.COM
	AT&T-Bell Labs / LZ 1H-303 / 201 576 6332
	307 Middletown-Lincroft Rd. / Lincroft, NJ  07738