Subject: Re: Clarification on NOW and BREAK
From: Tom Kazmierski (tjk@ecs.soton.ac.uk)
Date: Thu Oct 11 2001 - 08:28:41 PDT
At 15:10 11/10/2001, Craig Winters wrote:
1. Definition of NOW and Tc
| (...)
| when the analog solver resumes at time Tc it simultaneously
| resets Tn to a new value Tn' and determines a sequence of times
| Ti in the interval [Tc , Tn']. Tn' is the lesser of Tn and the
| least value in the interval [Tc , Tn] at which any signal
| Q'Above(E) becomes contradictory. The times Ti must include Tn'.
| At each time Ti the following steps occur:
| ...
| [none of these steps updates Tc]
I believe you are right. The steps listed in section 12.6.6 should include
an update of Tc=Ti in each cycle. This looks like a genuine omission so
I would like to invite more comments from 1076.1 WG members.
2. Can a break occur in a simultaneous statement?
You suggest further, that the LRM does not prevent a break from
occurring in a procedural simultaneous statement. This is incorrect,
as section 15.4 of the LRM quite specific:
"(...) It is also an error if a wait statement, a break statement,
or a signal assignment statement occurs in the procedural
statement part."
Regards
Tom Kazmierski
P1076.1 Chair
--- Department of Electronics and Computer Science,
--- University of Southampton, Southampton, Hampshire, SO17 1BJ,
--- UNITED KINGDOM
--- tjk@ecs.soton.ac.uk tel. +44 2380 593520 fax. +44 2380 592901
--- http://www.syssim.ecs.soton.ac.uk/
This archive was generated by hypermail 2b28 : Thu Oct 11 2001 - 08:47:27 PDT