> From: > Íhlund Magnus[SMTP:[log in to unmask]]
> Reply To: Íhlund Magnus
> Sent: Tuesday, September 28, 1999 12:58 PM
> To: [log in to unmask]
> Subject: Real time problem
> I am struggling with the following problem:
> After Object ACC has received event RELEASE, then object ACC shall activate
> CONSENT and then wait for 800 ms and then deactivate CONSENT.
> This is a requirement in my specification. I am using Ada in a large project
> and can't find out how I am supposed to assure that the time requirement
> above is fulfilled. This is a safety critical system.
> I am looking in the Annex D (Real Time) but can't seem to find a secure
Section D.2.2 and D.3 should help here. Apply these pragmas to order the ready queue by priorities.
> Maybe the delay until statement is a part of the solution, but how can I be
> sure that the ACC will deactivate CONSENT directly after those 800 ms ?
Make sure that ACC is a higher priority than CONSENT. Following the delay expiration, ACC will be at the head of the ready queue and preempt CONSENT. A simple delay statement should be adequate unless you need better resolution, or are executing cyclically.
> Maybe interrupts is an alternative solution ??
> Magnus Íhlund
> Celsius Aerotech
> [log in to unmask]