Newsgroups: comp.robotics,comp.realtime
Path: cantaloupe.srv.cs.cmu.edu!das-news2.harvard.edu!das-news.harvard.edu!news2.near.net!MathWorks.Com!europa.eng.gtefsd.com!howland.reston.ans.net!agate!dog.ee.lbl.gov!ihnp4.ucsd.edu!pacbell.com!amdahl!netcomsv!ix.netcom.com!netcom.com!fliptron
From: fliptron@netcom.com (Philip Freidin)
Subject: Re: Math chip for Embedded systems?
Message-ID: <fliptronCxCEIM.17z@netcom.com>
Keywords: math embedded chip
Organization: Netcom Online Communications Services (408-241-9760 login: guest)
References: <pauljoCx7L4E.FHw@netcom.com>
Date: Sat, 8 Oct 1994 07:08:45 GMT
Lines: 37
Xref: glinda.oz.cs.cmu.edu comp.robotics:14173 comp.realtime:7056

In article <pauljoCx7L4E.FHw@netcom.com> pauljo@netcom.com (Paul Johnson) writes:
>I am looking for a math chip which can be used with embedded systems.  
>I would prefer a buss oriented chip, where the host computer communicates 
>via an 8 or 16 bit data buss.  In my fantasy, I imagine a chip which uses 
>the IEEE floating point format used by Intel 80x87's and accepts one 
>number at a time followed by a command.
>
>Does anyone know of math chips of this, or any other design which can be 
>used with Intel 80c196KC/KD chips?
>
>Thank in advance,
>-- 
>Paul Johnson                | "It aint what you don't know that'll hurt
>pauljo@netcom.com           |  you, it's what you DO know that's wrong."
>75470.1721@compuserve.com   | - Attribution uncertain.

AMD used to make (and maybe still does) an IEEE floating point processor
that interfaced to ANY 8 bit micro, as a peripheral. PN# AM9512. It has
a stack, and you send data to it and commands 8 bits at a time. It was
quite fast for its time (1979). Handles single and double precission FP.
Clock rate was about 3 MHz, and +,- took max 512 cycles. *,/ took 256
clocks. Double precision took much longer.

There was also a non IEEE format version that came out in 1977, AM9511
that did +,- in 360 clocks, and *,/ in 180 clocks. The AM9511 also
did Integer +,-,*,/ on 32 bit integers, conversions, and trancendentals!

Intel also made them under the part numbers 8231 and 8232 (9511 & 9512)


By todays standards these are not very fast FPUs, but in their day, they
were the best game in town. All number above are from my memory, which
is as old as the chips :-)

All the Best
		Philip

