[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Spock@SAMSON.cadr.dialnet.symbolics.com: IFU]
Snail Mail Address: American Microsystems Inc. (A wholly owned
subsidiary of Gould Inc.) CAD Research Lab. P.O.
Box 967 Twain Harte, CA 95383
Phone Number: (209)586-7422
Date: Thu, 1 Dec 88 13:51 PST
From: Mabry Tyson <TYSON@AI.SRI.COM>
Yes, there are problems in the IFU. We have probably 25 or so IFU
machines. *Most* of them work fine most of the time. We've had a
couple of problematic machines. For some reason, the problems like you
described appear to occur on particular machines (even with different board
sets). My particular machine was plagued by the RPLACD errors. They seemed
to come in bunches. Another machine here was plagued with CALL-1 errors.
At least some people within Symbolics know there are problems. I seriously
doubt that anything will be done about it (I don't like it, but that may
just be life). It's sorta like the decision not to put an Ivory card out
to fit in the L-Bus machines. Not enough manpower nor enough market.
This is alright with me as long as there are viable alternatives.
Here is some code that I wrote to *try* to catch and prevent the CALL-1 errors.
This code should be considered somewhat untrusted as I've never seen it
correct the error. However, the machine it was put into was getting the errors
almost daily but it has been running with this code for about 2 weeks without
having the error occur. Notice that it tries to fix both a CALL-1 error and
an error on +. I haven't had the RPLACD problem since I wrote this code so
I haven't tried to incorporate it. Maybe you can... (This code is based on
an idea from someone inside Symbolics (who had his own code but flushed it
before I asked for it) but all coding mistakes are my own.)
And, yes, it usually does help to replace the IFU. But you may get the problem
Thanks for the code. I will probably use it as a band-aid until I can
get my MC board back. I like the performance boost of the IFU but it
doesn't seem worth it to me. I can't use the machine for long
unattended runs (which I need to do a *lot*) because it always seems to
bomb out *right* after I leave and 9 times out of 10 it's the IFU
problem. I'm not too fond of software fixes for hardware problems, but
I *sure* *appreciate* your help and I can put your code to good use.