On Jan 5, 2011, at 9:56 AM, Stephan Boettcher wrote:
> John Doty <j...@noqsi.com> writes:
>
>> I'd prefer a spice-prototype attribute, which would allow us to avoid many
>> of the difficulties without a confusing proliferation of attributes. For the
>> symbol nmos-3.sym, a suitable prototype might be:
>>
>> M? #D #G #S #S $model-name L= W= AS= AD= PS= PD= M=
>>
>> We can yell at each other about syntax, but I think the basic idea is sound.
>> Right now, spice-sdb is essentially reduced to guessing what the symbol
>> represents. It can't always tell reliably (it's been know to decide my
>> flip-flops are diodes!). There isn't generally one right answer: with a
>> different kind of model (subcircuit), the prototype for nmos-3.sym might be:
>>
>> X? #D #G #S $model-name
>>
>> Suggested syntax:
>>
>> First characters up to the "?" are the device prefix.
>>
>> #x means the net attached to pinnumber x.
>> %x means the net attached to pinseq x.
>> `x means the net attached to pinlabel x.
>> $x means the value of attribute x.
>> x= means an optional x=value string to be emitted only if the x attribute is
>> present.
>
> Same overloading, just sperad out, I don't like that.
Well, it's not quite the same, because the semantics are in the user's control
here. The alternative is a confusing proliferation of extra attributes. I don't
know that there's a perfect answer.
>
> Is this too verbose?
>
> M? #{pinlabel=D} #{pinlabel=G} #{pinlabel=S} #{pinlabel=S} ${model-name}
> L={length} W={width} AS= AD= PS= PD= M=
Yes, I think it is. Also note that we've for many years had l=, w=, m=, etc. as
special attributes in both SPICE back ends. Unfortunately, it isn't documented,
and the case sensitivity always trips me up (as it did above).
---
John Doty Noqsi Aerospace, Ltd.
This message contains technical discussion involving difficult issues. No
personal disrespect or malice is intended. If you perceive such, your
perception is simply wrong. I'm a busy person, and in my business "go along to
get along" causes mission failures and sometimes kills people, so I tend to be
a bit blunt.
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