[gta02-core] Values and units in schematics

Rene Harder rehar at saweb.de
Tue Jun 30 18:00:13 CEST 2009

Werner Almesberger wrote:
> I think we should continue following the multiplier-as-decimal-point
> convention, because it's just too easy to overlook a decimal point.
> Also bringing in the unit as a decimal point seems reasonable. (Only
> relevant for R, V, and maybe A.)

I agree, this notation is commonly used and I'd go for it as well.

> I'd lean slightly towards always capitalizing multipliers, also
> because the font size in schematics tends to be chosen such that
> upper case is readable, but with less regard to lower case.
> I don't think we have any milliohms anywhere, so we can avoid that
> problem :)

Well, but we might have millihenry somewhere in the schematics and then
we use M=Mega for resistors and M=milli for inductors?
That will lead to inconsistency and confusion, although i believe that
most people will know that 1M2 for an inductor actually means 1.2mH and
not 1.2MH.

So I'd rather go for the official writing style to prevent any upcoming

> I'm not sure whether to include units in general (as a reminder) or
> to omit them. Perhaps it's best to omit them for simple components
> (resistor, cap, inductor, etc.), and to include them for anything
> more complex, e.g., varistors.
> I'm undecided about the space. I tend to use a space in text (mails,
> comments, etc.), but when it gets more low-level (identifiers or
> component values), I don't use a space. A nice example for why a
> space is generally a good idea would be "10Ohm". Of course, this can

I would include units only where it's really necessary. 
That means where no multiplier is used (e.g 0R, 5V6  etc.),where it's
not clear which unit is meant or where the component has multiple
physical properties (e.g operating voltage, maximum current,
capacitance, ...) .

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