Engine on: a possible idea..

wrap a small coil around one of the spa=
rk cables (ignition).
When the engine is on, probably (?) you can detect=
 high voltage spikes that can sensed as a frequency by the PIC (before th=
is, is necessary to convert these pulses to a lower voltage and to a clea=
n wave with a simple circuit).
But if the engine is "Diesel" type..
=0D
=
regards
Marco



---------- Initial Header -----------

From     =
 : "pic microcontroller discussion list" PICLIST@MITVMA.MIT.EDU
To      =
    : PICLIST@MITVMA.MIT.EDU
Cc          :
Date      : Tue, 2 Dec 2003=
 12:18:18 -0500
Subject : Re: [EE:]  Voltage measurement

> Okay, than=
ks Tim & everyone else.  I'll digest all of
> these responses and figure=
 out how to do it.
>
> Tim - gotcha on the 'dead' battery.  It's actua=
lly a
> missing battery I'm worried about - fairly certain that
> will =
be 0v  :-).
>
> It sounds like the most difficult thing is going to be=

> differentiating between engine on and engine off.  Perhaps
> I can s=
et up a calibration routine where the chip measures
> and stores the vol=
tage readings during known engine-on and
> engine-off states & thus is c=
alibrated for that particular
> alternator/battery.
>
> Thanks!
> =0D
=
> -matt
>
>
> On Tue, 2 Dec 2003 11:21:29 -0500
>   Tim Hart <Tim.H=
art@HAWORTH.COM> wrote:
> >One more thing to watch out for.  A dead Lead=
 Acid
> >battery is not 0V.  It's 12.00V or so.  Each cell is
> >about =
 2.0 to 2.2 volts....6 cells and it's 13.2 for
> >fully charged and 12.0=
 for empty.
> >
> >And I'm with the group on this one....a resister div=
ision
> >network and a PIC with A/D is the way to go....
> >
> >Tim=0D
=
>
> --
> http://www.piclist.com hint: To leave the PICList
> mailto:p=
iclist-unsubscribe-request@mitvma.mit.edu
>

--
http://www.piclist.com hint: PICList Posts must start with ONE topic:
[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads