Re: How to get Ada to ?cross the chasm??

[Dennis Lee Bieber <wlfraed@ix.netcom.com>]

On Sun, 13 May 2018 10:03:18 -0700, Paul Rubin <no.email@nospam.invalid>
declaimed the following:


>Well I've never worked on such an application in real life (I arrived at
>this subject through being interested in logic and proofs as topics in
>math) so you know way more than I do about how they actually work.  But
>I imagine the app being something like an engine controller in a car.
>
>So there might be some variables counting how many anomalies of a
>given type had occurred, or maybe even a log of the past N such events
>for some small fixed N, and there'd be no persistent memory so you'd
>have to connect the ECU up to an analyzer before powering it off, or
>maybe even run your diagnostics with the analyzer connected.
>
>Maybe in todays cars the ECU could send log data to some centralized
>logging computer constantly but the other receiving end would be
>non-critical.
>

	OBD-II defines a set of available error codes, and the ECU likely has
an array defined for each code supported (not all standard codes need to be
used by all vehicles). For each slot/code, a time-stamp of last occurrence,
a count of repeats (and a count of non-repeats -- some codes will clear
after a number of success cycles).

	IOWs; the log is bounded -- it is not something like a Linux syslog
file that just grows based upon the amount of logged activity until some
operation may rotate files...



-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
	wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/