Minutes from the meeting of the European WG on VHDL_A
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The two day meeting of the Analogue VHDL WG was held at CNET in Grenoble on
21st and 22nd of January 1993. The following persons attended the meeting:

Mart Altmae (IM)    			Jean-Michel Berge (CNET/CNS)
Helene Durantis (Thomson CSF)  		Claude le Faou (CNRS)
Jorg-Olivier Fischer-Binder (R.Bosch)	Serge Garcia-Sabiro (ANACAD)
J.J. Mayol (ANACAD)			Jean Mermet (ECIP Office)
Dominique Rodriguez (ANACAD)    	Jacques Rouillard (IMT)
Denis Rouquier (CNET/CNS)   		Wojciech Sakowski (ECIP Office)
Hazem El-Tahawy (ANACAD)         	Alain Vachoux (EPFL)

Alain Vachoux presented the version 1.0 of the Design Objectives Document,
that includes 52 design objectives (DOs) based on requirements collected
and verified during the requirement analysis phase. 

The DOD document should be available soon at the ECIP VHDL electronic 
repository (see below) as a postscript file or at least as a plain text
(there are some difficulties in handling the postscript version at
the moment).

Jean-Michel Berge proposed a standard template for "Language Extension
Specification (LES)". It should allow for structuring the work during
language design. 

Helene Durantis presented some specific requirements from
the user point of view (including small signal analysis and non-linear
spectral analysis), what resulted in introducing the notion of
"interpretation domain". 

The presentation of the "equation-unknowns" by Serge Garcia-Sabiro 
was followed by proposals concerning equation statements (by J.M. Berge). 

Denis Rouquier explained the notion of "analogue boxes" (renamed afterwards 
to "equation sets") as well as possible A/D and D/A conversion mechanisms. 

Finally Serge Garcia-Sabiro presented proposals for dimensional analysis.

The discussion during the second day of the meeting resulted in renaming
and structuring the objects and mechanisms that are needed to model
analogue circuits and thus will constitute the basis for VHDL-A. They
include: 
- float, complex and "analogue" types, 
- analogue quantities, equation
- statement and equation sets, 
- "coupling" of analogue model substructures,
- natures (e.g. electrical, mechanical - including the notions of through and
	access values), 
- pins and nodes (being analogue counterparts of ports and signals),
- an analogue event,
- a simulation cycle (for transient analysis),
- interpretation domain and 
- dimensional analysis. 

It was decided to define an intermediate document ("Glossary") that will
contain the definitions of all these notions (objects, structures,
mechanisms etc.) as well as cross-references to the DOs, which they address
and to these LESs, which are aimed to implement them. This document will be
prepared for presentation during the DASS meeting in the second half of
February. 

Alain Vachoux (EPFL-Lausanne, phone: +41 21 693 69 84, fax: +41 21 693 46 63, 
e-mail: vachoux@ legsun1.epfl.ch) and Jean-Michel Berge (CNET-Grenoble, phone:
(+33) 76 76 43 35, fax: (+33) 76 90 34 43, e-mail: berge@cns.cnet.fr) are
European co-chairs for a language design phase. 
__________________________________________________________________________
The VHDL technical documents repository was established on imag.fr server
at Pole Europeen de Grenoble in December. The repository will gather
technical documents, that are not copyrighted as well as working documents
resulting from different activities related to VHDL standard (minutes from
the WG meetings, technical requirements and design objectives documents,
related to different new initiatives etc., interesting e-mail debate
contributions etc.). 

The contents is available to everybody. In order to access the repository
it is necessary to connect to imag.fr by means of ftp, login as anonymous
(providing one's own address as a password) and change the directory to
PUB/VHDL/. There is a readme file inside that summarises the current
contents of the repository. The contributions should be sent via e-mail to
sakowski@imag.fr.