delorie.com/archives/browse.cgi   search  
Mail Archives: geda-user/2016/01/04/17:19:15

X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f
X-Recipient: geda-user AT delorie DOT com
X-TCPREMOTEIP: 63.119.35.194
X-Authenticated-UID: jpd AT noqsi DOT com
Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\))
Subject: Re: [geda-user] Project leadership
X-Pgp-Agent: GPGMail 2.5.2
From: John Doty <jpd AT noqsi DOT com>
In-Reply-To: <CAJXU7q_H54n7-iyephsGF8DnSvu2f1zv_jqkFsthDwVCVa7BnQ@mail.gmail.com>
Date: Mon, 4 Jan 2016 17:18:45 -0500
Message-Id: <2B07BB75-1CF0-4A30-985C-893E8DCAEE54@noqsi.com>
References: <5AC3D5C5-144F-41AE-9562-47BC34D9047F AT noqsi DOT com> <CAJXU7q_GnuGNMtUWkB-xgBiKgY5R5W4ZCjtnz5EJizG+46dm1w AT mail DOT gmail DOT com> <C7FDF8B6-B335-46C3-8A25-F95ACECF4B79 AT noqsi DOT com> <CAJXU7q_3XwthnN_8mp7B+-ShHeK+=7J=54ZavKBUG3S3bSKp2A AT mail DOT gmail DOT com> <20151222193859 DOT 26898 DOT qmail AT stuge DOT se> <20151223202851 DOT 637d5b1f AT jive DOT levalinux DOT org> <20151223195846 DOT 8392 DOT qmail AT stuge DOT se> <CAM2RGhS2bg=Rjuq6oEeOacV7PfUENy_jq7dxag=vWsUbdH6pAQ AT mail DOT gmail DOT com> <20151229155647 DOT GA3752 AT localhost DOT localdomain> <CAM2RGhSLND5+JSSj=1cUPUhzkTCK6d7NZ61QL-eViZRccY5LqA AT mail DOT gmail DOT com> <20151229175222 DOT GD3752 AT localhost DOT localdomain> <alpine DOT DEB DOT 2 DOT 11 DOT 1512311656190 DOT 1475 AT newt> <96A12FC1-E09C-4D63-8346-5A62FDAB4228 AT sbcglobal DOT net> <alpine DOT DEB DOT 2 DOT 11 DOT 1512311916190 DOT 12724 AT newt> <2F0AFAE8-ADAB-4DE0-A79C-DD87077E66B5 AT sbcglobal DOT net> <alpine DOT DEB DOT 2 DOT 11 DOT 1601010135550 DOT 2280 AT newt> <CAJXU7q_H54n7-iyephsGF8DnSvu2f1zv_jqkFsthDwVCVa7BnQ AT mail DOT gmail DOT com>
To: geda-user AT delorie DOT com
X-Mailer: Apple Mail (2.1878.6)
Reply-To: geda-user AT delorie DOT com
Errors-To: nobody AT delorie DOT com
X-Mailing-List: geda-user AT delorie DOT com
X-Unsubscribes-To: listserv AT delorie DOT com

--Apple-Mail=_31857315-E68F-4DE0-B306-33C89DC5F977
Content-Type: multipart/alternative;
	boundary="Apple-Mail=_FE4E2689-36EB-4F3D-8419-164B07B049C6"


--Apple-Mail=_FE4E2689-36EB-4F3D-8419-164B07B049C6
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain;
	charset=windows-1252

Peter, have you looked at https://github.com/noqsi/gnet-spice-noqsi?

On Jan 4, 2016, at 7:12 AM, Peter Clifton =
(petercjclifton AT googlemail DOT com) [via geda-user AT delorie DOT com] =
<geda-user AT delorie DOT com> wrote:

>=20
> On 4 Jan 2016 14:00, "Roland Lutz" <rlutz AT hedmen DOT org> wrote:
>=20
> > Thinking about it, I'm not even sure if this behavior (treating the =
slots of a package as individual SPICE objects) is even necessary.  The =
other SPICE backends don't seem to be using it.
>=20
The history of this is complicated. There was a time years ago when a =
broken libgeda wound up in distribution because of a failed attempt to =
make slotting work =93right=94 for both layout and SPICE. But what=92s =
right for SPICE depends on context. Can you ignore crosstalk within a =
package (maybe it=92s the most important thing you=92re modeling)? If =
you can, and the SPICE model you have is for one slot (a very common =
scenario), you may want to accommodate that. Otherwise, you probably =
want to have one object per package.

This issue was my most important motivation for writing =
gnet-spice-noqsi, which allows the user to control the connections of =
model instances to nets through the spice-prototype attribute. This =
works at the symbol level, or even the instance level, with defaults =
that imitate gnet-spice-sdb.

Is the current behavior of gnet-spice-sdb for slotted devices documented =
anywhere?
> An alternative option would be to have a (schematic or netlist based) =
sub-model which maps the connections of the actual part, to 'n' internal =
instances of the cell model.
>=20
>=20

Gnet-spice-noqsi makes this a user choice.
> It really depends on whether you are viewing the schematic and spice =
simulation as that of the design with actual parts, or at a more =
abstracted level where actual embodiment of the opamp cells means =
picking what chip they go in.
>=20
>=20

Yes. And in the process of turning an idea into a finished design, you =
may go through intermediate states that mix abstract and concrete. Even =
when you have a finished design, the SPICE =93test fixture=94 is usually =
a rather abstract piece of circuitry. That=92s why the back end needs to =
allow the user to control the expression of a device in the SPICE =
netlist. It also needs good defaults, of course, so you don=92t need to =
hold its hand about every resistor.

John Doty              Noqsi Aerospace, Ltd.
http://www.noqsi.com/
jpd AT noqsi DOT com



--Apple-Mail=_FE4E2689-36EB-4F3D-8419-164B07B049C6
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html;
	charset=windows-1252

<html><head><meta http-equiv=3D"Content-Type" content=3D"text/html =
charset=3Dwindows-1252"><meta http-equiv=3D"Content-Type" =
content=3D"text/html charset=3Dwindows-1252"><meta =
http-equiv=3D"Content-Type" content=3D"text/html =
charset=3Dwindows-1252"></head><body style=3D"word-wrap: break-word; =
-webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">Peter, =
have you looked at&nbsp;<a =
href=3D"https://github.com/noqsi/gnet-spice-noqsi">https://github.com/noqs=
i/gnet-spice-noqsi</a>?<div><br><div><div>On Jan 4, 2016, at 7:12 AM, =
Peter Clifton (<a =
href=3D"mailto:petercjclifton AT googlemail DOT com">petercjclifton AT googlemail DOT co=
m</a>) [via <a =
href=3D"mailto:geda-user AT delorie DOT com">geda-user AT delorie DOT com</a>] &lt;<a =
href=3D"mailto:geda-user AT delorie DOT com">geda-user AT delorie DOT com</a>&gt; =
wrote:</div><br class=3D"Apple-interchange-newline"><blockquote =
type=3D"cite"><p dir=3D"ltr"><br>
On 4 Jan 2016 14:00, "Roland Lutz" &lt;<a =
href=3D"mailto:rlutz AT hedmen DOT org">rlutz AT hedmen DOT org</a>&gt; wrote:</p><p =
dir=3D"ltr">&gt; Thinking about it, I'm not even sure if this behavior =
(treating the slots of a package as individual SPICE objects) is even =
necessary.&nbsp; The other SPICE backends don't seem to be using =
it.<br></p></blockquote><div>The history of this is complicated. There =
was a time years ago when a broken libgeda wound up in distribution =
because of a failed attempt to make slotting work =93right=94 for both =
layout and SPICE. But what=92s right for SPICE depends on context. Can =
you ignore crosstalk within a package (maybe it=92s the most important =
thing you=92re modeling)? If you can, and the SPICE model you have is =
for one slot (a very common scenario), you may want to accommodate that. =
Otherwise, you probably want to have one object per package.<br><br>This =
issue was my most important motivation for writing gnet-spice-noqsi, =
which allows the user to control the connections of model instances to =
nets through the spice-prototype attribute. This works at the symbol =
level, or even the instance level, with defaults that imitate =
gnet-spice-sdb.<br><br>Is the current behavior of gnet-spice-sdb for =
slotted devices documented anywhere?<br></div><blockquote type=3D"cite"><p=
 dir=3D"ltr">An alternative option would be to have a (schematic or =
netlist based) sub-model which maps the connections of the actual part, =
to 'n' internal instances of the cell =
model.</p><div><br></div></blockquote><div><br></div>Gnet-spice-noqsi =
makes this a user choice.<br><blockquote type=3D"cite"><p dir=3D"ltr">It =
really depends on whether you are viewing the schematic and spice =
simulation as that of the design with actual parts, or at a more =
abstracted level where actual embodiment of the opamp cells means =
picking what chip they go =
in.</p><div><br></div></blockquote><div><br></div>Yes. And in the =
process of turning an idea into a finished design, you may go through =
intermediate states that mix abstract and concrete. Even when you have a =
finished design, the SPICE =93test fixture=94 is usually a rather =
abstract piece of circuitry. That=92s why the back end needs to allow =
the user to control the expression of a device in the SPICE netlist. It =
also needs good defaults, of course, so you don=92t need to hold its =
hand about every resistor.<br></div><br><div =
apple-content-edited=3D"true">
<span class=3D"Apple-style-span" style=3D"border-collapse: separate; =
border-spacing: 0px;"><p style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><font =
face=3D"Helvetica" size=3D"3" style=3D"font: 12.0px Helvetica">John =
Doty<span class=3D"Apple-converted-space">&nbsp; &nbsp; &nbsp; &nbsp; =
&nbsp;<span class=3D"Apple-converted-space">&nbsp;</span><span =
class=3D"Apple-converted-tab">&nbsp; &nbsp;<span =
class=3D"Apple-converted-space">&nbsp;</span></span></span>Noqsi =
Aerospace, Ltd.</font></p><p style=3D"margin: 0.0px 0.0px 0.0px =
0.0px"><a href=3D"http://www.noqsi.com/">http://www.noqsi.com/</a></p><p =
style=3D"margin: 0.0px 0.0px 0.0px 0.0px"><font face=3D"Helvetica" =
size=3D"3" style=3D"font: 12.0px Helvetica"><a =
href=3D"mailto:jpd AT noqsi DOT com">jpd AT noqsi DOT com</a></font></p><br =
class=3D"Apple-interchange-newline"></span>
</div>
<br></div></body></html>=

--Apple-Mail=_FE4E2689-36EB-4F3D-8419-164B07B049C6--

--Apple-Mail=_31857315-E68F-4DE0-B306-33C89DC5F977
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
	filename=signature.asc
Content-Type: application/pgp-signature;
	name=signature.asc
Content-Description: Message signed with OpenPGP using GPGMail

-----BEGIN PGP SIGNATURE-----
Comment: GPGTools - https://gpgtools.org
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=mxZ5
-----END PGP SIGNATURE-----

--Apple-Mail=_31857315-E68F-4DE0-B306-33C89DC5F977--

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019