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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Build language with weak typing,
 then add scaffolding later to strengthen it?
Date: Fri, 29 May 2015 10:27:53 +0100
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Date: 2015-05-29T10:27:53+01:00
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jan.de.kruyf@gmail.com writes:

> In the thread about the shortest path through a task Simon came up
> with some number for interrupt latency in Ravenscar that horrifies
> me. Surely the object of the exercise of having interrupts at all is
> defeated by now, At least in my application. (High speed motion
> control)

To me, 6 us didn't seem too bad. You have to pay for using high-level
constructs (high-ish, in the case of Ravenscar, of course).

But then, I remember the manual-guide-torpedo-by-wire system where the
team were pleased they'd got the feedback loop time (move joystick to
response from torpedo on screen) down from 50 s to 15 s. When asked
whether he found it a problem, the CPO said that submariners are used to
taking things slowly :-)

I should add, the RTS that I timed is based on FreeRTOS. Guess I should
do the same timing with AdaCore's RTS.