Parallel port -> Various Car functions

**Lum** · 09-14-2006, 01:56 PM

I was just reading the radio thread where someone asked it were possible to have their power aerial extend when they turn the radio on (typically the function of the blue wire on a car head unit)

I have been wondering about an unrelated but similar feature, to have the screen dim be controlled by my switching the car's lights on (this is controlled by the orange wire on a head unit)

I am not sure what other features people can come up with, but these two at least could easilly be controlled by the parallel port. You'd just need to build 12V<-->5V transformers so you don't blow up your motherboard.

Do you think it's worth coming up with some kind of open standard for these functions that CF and other front ends can support, presumably then some people can sell pre-made LPT->ISO leads to those who don't want to make their own

**Jman** · 09-15-2006, 01:11 AM

I would also like to auto pause CF when i use my phone via it's Nokia bluetooth kit . Most kits of this type have an output for radio mute/pause.
If we could use the p/port this would be great.

John

**veetid** · 09-15-2006, 02:53 AM

Originally Posted by Jman

I would also like to auto pause CF when i use my phone via it's Nokia bluetooth kit . Most kits of this type have an output for radio mute/pause.
If we could use the p/port this would be great.

John

There is a hotkey for it and girder... all you have to do is wire it up...

david

**Jman** · 09-15-2006, 02:30 PM

Damm i didn't think of that
Thanks i gonna do that

Jman

**ShawJohn** · 09-15-2006, 02:33 PM

my headunit does this for me

**AllShowNoGo** · 09-18-2006, 04:43 PM

check out this link: http://www.epanorama.net/circuits/pa...l#relaycontrol

I have used the simple circuit design in the past with no damage to my motherboards. Since you only need one output, i suggest using a solid state relay. They use opto isolation so it can't hurt your motherboard. Not sure if your going to need resistor to keep it from pulling too much current from the port. If you are using XP or 2000 you will probably have to install a driver to access the parallel port from dos.

If you look elsewhere on that page theres info about controlling the port using a web interface. If a small webserver is run and you have wireless networking, you could easily build a remote starter. Just make sure you have security on the webpages.