1 Wire GPIO outputs

if you use onewire.Write then the output will latch at the desired value until your code asks it to change.

Thanks so very much.

Although I've been playing with computers since the late '70s, this is my first tempt to use an Arduino, but it probably won't be my last.

Everyone seems to love to use the one-wire to read things, but have not found one single mention about how to use it to Write stuff.

I just may have to put together a circuit to try it out and make a short tutorial on it.

Thanks again for your answer.

Tom

You're welcome. Let me know if you require any assistance with code.

Again, thanks for the offer.  Who knows.

Anyone know off the top of their head who this one wire system was first "invented" for?  (And who never used it...)

And another application that saw it, and liked it, and went to town using it?

Tom

This says Dallas inented it.

http://en.wikipedia.org/wiki/1-Wire

Why is probably for external sensors.

Mark

This may, or may not, be direct lineage.

But a similar "1-wire" configuration was proposed to link together many remote sensors in large aircraft.  If I recall correctly, it was actually a three wire version, gnd, positive, and data.  One idea was that some items need to be polled, or commanded, much more frequently than others.

Even small aircraft can get bogged down with lots of control wiring going to various parts of the aircraft.  Several helicopter manufacturers use variations of normal wire to save space.  Bell uses a type of wire with a very thin brown insulation to save space.  I've been told that you can overload one wire in the middle of a bundle until the conductor melts out the ends of the insulation, without harming the rest of the bundle.

Hughes Hellicopters used to use (and probably still uses) a very small shielded audio cable, with the outside diameter much smaller than average shielded cable, just to keep bundles of cable small enough to run through the lightening holes in the structural portions of the aircraft.

But I'm not aware of any manufacturer using the earlier version on aircraft.  But it was apparently adopted in mass by the submarine builders.  The space just inside the hull of most submarines can get very crowded very quickly with huge wiring bungles.  But for redundancy, the have gone to three complete systems running to each, and some small computer in each remote device checks to see if the three lines agree, and discards the errant line.

But then I don't have any actual first hand knowledge of submarines, except the ones I've visited in various museums.

Tom

Yep that's why it's referred to as the Dallas 1 wire bus.... At least to those I know.

Any way that probably got dropped when Maxim bought them ..

http://news.cnet.com/Maxim-buys-Dallas-Semi-for-2.5-bln/2100-12_3-260799.html

I thought that was only a year or two now I see it's 13 years ago !!!