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From: raveling@vaxb.isi.edu (Paul Raveling)
Newsgroups: comp.arch,comp.software-eng
Subject: Re: using (ugh!  yetch!) assembler
Message-ID: <6132@venera.isi.edu>
Date: 23 Aug 88 16:17:59 GMT
References: <60859@sun.uucp% <474@m3.mfci.UUCP% <2926@utastro.UUCP% <37014@linus.UUCP% <9763@eddie.MIT.EDU% <37247@linus.UUCP% <1148@anasaz.UUCP> <3008@ttidca.TTI.COM> <2689@jpl-devvax.JPL.NASA.GOV>
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In article <2689@jpl-devvax.JPL.NASA.GOV> leem@jplpro.JPL.NASA.GOV (Lee Mellinger) writes:
>
>...Shuttle onboard software for the four AP-101 computers (not the backup
>machine), and have been for the life of the project.  The shuttle code
>is written on a mainframe computer in HAL/S and machine code ...

	I had an impression, but don't recall with certainty, that
	the backup computer's software was assembly language.  This
	impression was from a software engineer who worked on it and
	moved from Rockwell to my group at FutureData late in 1980.

	Another avionics example is the B1-B Central Air Data Computer,
	which was about 50% assembly language, 50% PLM/86 when I
	worked on it.  This, along with all the other avionics software
	I've seen, needed hand-optimized assembly code to meet its
	real time requirements.


---------------------
Paul Raveling
Raveling@vaxb.isi.edu