[Gllug] 2.6.31 is out

[Geo]

On Tuesday 15 September 2009 00:29:21 Peter Corlett wrote:
> On 14 Sep 2009, at 23:59, Geo wrote:
> [...]
>
> >> Commercial units are probably as rare as hen's teeth now, but they're
> >> also really simple and suitable for a first electronics project.
> >> (Especially as there's about a fiver's worth of parts in it, tops,
> >> and
> >> they seem to sell for ten times that.)
> >
> > do you have aURL for the design etc of one of these units by any
> > chance?
> > thanks
>
> No, but they're so simple you don't need a schematic. You attach a bi-
> colour LED and suitable drop-resistor (1K should be about right)
> between signal and ground on all of the serial lines you are
> interested in.
>
> A bi-colour LED is basically a red and green LED inside the same
> package, connected so that it glows red if the current flows in one
> way, and green if it flows the other. Since RS232 uses a positive
> voltage for 0 and a negative voltage for 1, the LED colour (or lack
> thereof) indicates the state of the line.

Thank you for that Peter.


-- 
TTFN
   Caparo
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