Chips that changed the world

Warren Wolfe lists at databasics.us
Sun May 3 19:32:14 CDT 2009


Ray Arachelian wrote:

    Keep in mind that there are things such as deadlines to consider, so
    quick and dirty tricks like those, look nasty in hindsight, and
    certainly take a lot of time to clean up afterwards, but they do get the
    job done for the moment. How many programming teams consider the
    long run versus "just get it out the door"? Or I should say, how many
    programmer's managers consider the long run? :-)
    Individuals almost always care about their work and want to do a job
    that will last, despite deadlines or pressure to cut corners. But
    managerial pressure to do the wrong thing usually prevails.

Yes, Ray, that's vitally important.  Good call.

A company I was with, Systems Research, Inc., made a Burroughs TD-830 
Emulator terminal.  When they were done with that, they had about 1 K 
(Yes, 1 K) of ROM space, and wanted to know if the machine could ALSO be 
programmed to be a regular ANSI terminal as well.

As it turns out, yes, it could.-- sort of.  The first job was to take 
the 31-K TD-830 code, and make it more efficient.  That got about 
another 4 K, and was politically very difficult, as the TD-830 people 
were in a different group, and got huffy at us improving their code.  
Then the TTY code was written with an INCREDIBLE number of "dirty 
tricks."  Of course, we called routines already written for the TD-830 
whenever possible, and, truth be told, sometimes when it was NOT 
possible.  at one point, we hopped into a text message which terminated 
(as did they all) with a byte of 00H, which is a NOP for the Z80, and 
then fell into another routine.  ASCII characters tend to be 
register-to-register moves, we just loaded different registers with 
input values, and used some of the effects to save a dozen or so bytes 
of code.  When all was said and done, it worked, an we had 5 extra 
bytes, so we wrote a "LIFE" program.  (Just kidding.)  Anyway, the 
project manager later said that we had used everything but the top half 
of the blue bytes.

Also, by comparison, note that AT&T was prohibited from selling or 
licensing Unix as a commercial product until about 1984, though thy DID 
place it in universities.  The point is that they did NOT have "market 
pressures" for new releases, and because of that, produced a huge, 
complex, quite possibly bug-free product that is a joy to use.  And I'm 
not sorry to sound like an evangelist -- Unix is the best software ever 
written by humans.  It was also originally conceived in the 1960s, and 
made it into reasonable use in the early 1970s, so its OLD software, for 
purposes of OT discussion.  The Mac world has recently made a massive 
improvement by going to an O/S based upon a flavor of Unix.  Now, we 
need to do that for the PC world, and normal progress can resume.  
There's no need to be chipping new wheel designs out of stone when we 
have an independent suspension chassis available, and can bolt on any 
body we want.  Let the programmers develop gee-gaws and new user 
interfaces for it, but the core, the user and process handling and the 
file system of Unix are WAY better than any other attempt so far.  Linux 
is a variant, and free.  So....  "Not Invented Here" is the only reason 
to use another base O/S, at least until something better comes along.

</sermon>

Peace,

Warren



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