K-line?
CAN?
XDE?
JDOT?
DIS 14230?

Is a few off the top of my head, Which two is it?

Dennis


> -----Original Message-----
> From: Damon Hopkins [SMTP:mdhopkin@UNITY.NCSU.EDU]
> Sent: Friday, 19 May 2000 16:10
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Re: [EE] Interfacing PIC to automotive electrics?
>
> "Gennette, Bruce" wrote:
> >
> > Hi all,
> >
> > Probably been explained before, but how do I interface a 5V PIC to the
> > signals coming from 12V car (and 24V truck) devices like temperature and
> oil
> > pressure sensor/senders?
> >
> > I suspect that cars can use CMOS comparitors set against a trim pot
> (with
> > zeners to divert any spikes), but how about truck (or boat) engines
> using
> > 24V?
> >
> > Could I use voltage dividers to bring the signals down to the 0-5V range
> and
> > directly connect to a PIC or TTL gates?
> >
> > For this first project I'm just looking at the alarm state ( !Ok ), but
> > later I may want to log all parameters so that a progressive failure can
> be
> > spotted (eg cooling water temp hotter each day indicates a growing
> blockage
> > in the system or excessively worn pump).
> >
> > If there is an existing FAQ could someone point me to it please?
> >
> > Thanxs in advance,
> > Bye.
>
> There's an article about the network systems in cars in the current
> issue of Circuit Cellar.. If you can't find it let me know I can look up
> what the documents are you need. It basically tells you about the 2
> major different kinds of car networks and what SAE manuals to get w/ all
> the details.  I forget which issue (MAY perhaps april) but the cover is
> mostly black :)
>
> Let me know if you can't get ahold of it and I'll throw you some
> pointers from the text..
>
>                         Damon Hopkins