Path: utzoo!attcan!uunet!husc6!bloom-beacon!gatech!sbmsg1!scbhq!uahcs1!madhat!alvitar
From: alvitar@madhat.UUCP (Phil Harbison)
Newsgroups: comp.arch
Subject: Re: Split I and D caches and IBM lawyers
Keywords: IBM, patents, SUN
Message-ID: <278@madhat.UUCP>
Date: 6 Aug 88 22:58:59 GMT
References: <62370@sun.uucp>
Organization: DataVision, Huntsville AL
Lines: 35

In article <62370@sun.uucp>, dre%ember@Sun.COM (David Emberson) writes:
>                                      ^^^
> Now that IBM has supposedly "invented" Harvard architecture with cache
> memories ...
> 
> If ever there was a case which proved the need for more vigilance on the
> part of the patent office and the legal profession, this is it....
>
> Common subexpression elimination?  Gimme a break!  Single cycle mask and 
> rotate instructions?  Come on!  Where will this end?
> 
> We need a patent system that 1) prevents trivial claims, 2) is inexpensive,
> and 3) provides protection for small companies and entrepreneurs.
> 

Is it  just me  or do  others see  the irony in this statement?  Here we
have  a  guy  complaining  about  IBM's ability to patent such "obvious"
things  as  separate  I&D caches, common subexpression elemination, etc.
However,  a quick glance at the authors signature line tells me he works
for  SUN  Microsystems,  the  same  company which was able to patent the
"revolutionary"  concept  of  using the least significant bits of an ad-
dress  as  the row addresses for a bank of DRAMs.  Is this not a case of
the pot calling the kettle black? 

Of  course  I am referring to the patent SUN has on using the bits which
bypass  the  MMU  as  row  addresses, thereby allowing the row access to
overlap  with  the MMU translation time.  Never mind the fact that it is
convention to use the LSBs as the row address anyway, and that the over-
lap  potential  should  be  obvious to anyone skilled in digital circuit
design.   In  my  opinion, SUN is just a little IBM that just happens to
have better tastes in processors and operating systems.  :-)

By the way, this is not meant as a personal attack on Mr.  Emberson.  My
complaints  are with the SUN coorporation, not its individual employees,
who for the most part are very nice people. 

----
Live: Phil Harbison
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