PC Power Control Cable

**timekiller** · 11-05-2007, 04:30 PM

Ok, This is a long shot question, but I'm desperate

I bought a Double Din touchscreen HU (some know it as the DWW-6500, others as a CID650). This guy: http://www.digitalww.com/store/prodd...p?prod=DWW6500

The unit has buttons to power and reset the carpc. But I am unclear on how they work. I was expecting the buttons to work as an extension of the pc power/reset buttons. This is not the case though. Instead the HU has a wire labelled "PC Power" and another labelled "PC Reset". The manual is poorly translated and is not very helpful. Anyone interested can download it here: http://www.cartft.com/support_db/sup...les/CID650.pdf

Has anyone figured out how to wire this thing? Or at least seen a similar setup where a single wire is used for "PC Control" ???

In testing I put a volt meter across the "PC Power" and ground, I got a steady 4.88 volts, and when I set the PC Power to "off" on the HU, the voltage dropped to 0. I thought I could use a relay to control the 12v+ line to my carpc, but I could not get the "PC Power" line to trip the relay, even though the pickup voltage of the relay claims to be 3.5v. I testing the relay with a 9v, and it tripped fine, just not off the "PC Power" control cable

Anyone have a clue on this ?

**v8 scimitar** · 11-05-2007, 06:44 PM

Hmmm it is a bit unclear, is the green/white and red/black single cables that are multy coloured or is there actually a red and a black wire? If they are multi coloured then pass, I have no idea how it can work with just one wire each. If it is multi wire then they will go onto the header pins of the mobo the same as the power and reset do from a case.

**CarputerTech** · 11-07-2007, 05:08 PM

I got your PM about this, here are my thoughts:

The DL065A/CID650/DWW-6500 (all the same unit) have two wires coming out the back. One is reset, and the other is power. If I remember correctly, whenever you actuate the buttons, the wires are pulled into a low state. For instance the reset wire is normally open (or in a high state, but with very low current), but when you press the reset button, the wire is pulled to ground. If you were to attach a voltmeter to this wire and a +5v supply, it will read +5v when the switch is pressed.

I believe most reset buttons on motherboards are active low, meaning when they get pulled to ground they do their thing (ie reset the processor).

Be sure to test this out ahead of time, but you should be able to take the ground and attach it to your pc, then the reset line to the reset pin on your motherboard.

BE CAREFUL when testing with a relay. These types of wires are typically very low current. So they will not drive a relay themselves, you'll need a transistor (with a protection diode) between them to switch the relay.

Hope that helps!