Paul wrote:

The processor we use to control the throttles is a Motorola MC68HC16Z1
running at 16.77 MHZ.  The control software is written in Assembly.
Dr. Moller

Thank you for answering that. That is about what I would do as
the 68HCxxx processor has a definitive time for executing instructions unlike
the more powerful Intell PC processors. Assembly language gives the
programer precise control over execution times unlike most higher
level languages.

Ummm... I have extensive experience in programming microprocessors,
including several years as a systems programmer writing assembly
language for embedded micros.

IMHO, writing any significant amount of software in assembly language is
anachronistic. Processors nowadays are so fast and compilers so good
that it's just not necessary in most cases. Nowadays, the average C
programmer produces faster code than the average assembly language
programmer. And, of course, it's much less buggy and takes less time to
produce.

What's more, managing something real-time like engine throttles just
doesn't take much computer horsepower. Assuming an engine is running at
6,000RPM, a 16.77MHz processor could execute up to 2,800 instructions
for each *revolution*. I'd guess that that would be about enough power
to manage the throttle, so it could be adjusted every single revolution.

Frank.

What sort of real time systems did you program Frank?

Paul Lamar
 
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