# Steering Wheel controls as volume knob for tablet? What adapter to use for output?



## audionublet

I've come across this video http://youtu.be/pDgeaiIaz_U

I'm trying to figure out how exactly how this is being done. I'm interested in putting the new Galaxy Tab 7.7 in my dash, but really don't want to use an external volume knob.

Also, AFAIK the G-tab lacks any type of line-level audio outputs, what are people using for this?

I'm scratching my head on how this is done...lol. I've posted this on MP3car and no real response yet.

Links are appreciated!


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## stochastic

I'm considering adding a carputer to my setup, but I don't want to give up the steering wheel remote. The method I plan to use (if I go for the carputer) is to take out my wiring schematics and a circut tester to record the wiring from the remote. Then I'll adapt those wires to a serial input on the computer, program up a little magic to correspond to the incoming control signals, and away we go.

I'm sure if I was going to use a pre-fab computer like the Galaxy, then I'd need an extra step of hackery to figure out a method for the serial input. If the volume knob is all you're concerned about using, then you should be easily able to wire into the already existing volume control on the Galaxy - but don't mod it without testing the voltages.


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## porscheman

not sure what the tab has for usb ports, but this is what a lot of people are using to keep the factory steering wheel controls with a carpc
RcJoyCon - Control Car PC with Steering wheel controls
i know the dude is in korea, but he does ship fast and i think mp3car.com has picked them up in store. works flawlessly for me in my cube, i have 2 loops going to the wheel and had to add a little resistance into one of them so it would work. they shared a common ground and were identical values on both sides


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## ninja6o4

porscheman said:


> not sure what the tab has for usb ports, but this is what a lot of people are using to keep the factory steering wheel controls with a carpc
> RcJoyCon - Control Car PC with Steering wheel controls
> i know the dude is in korea, but he does ship fast and i think mp3car.com has picked them up in store. works flawlessly for me in my cube, i have 2 loops going to the wheel and had to add a little resistance into one of them so it would work. they shared a common ground and were identical values on both sides


I ordered one from Mo Co So here, admittedly he was out of stock at the time so it took 2 weeks but once he received his inventory i got it in about 3 days. Have not hooked it up yet but heard great things about it.


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## JayinMI

Now we just need software for Android tablets. 
Cool piece, and very reasonably priced.

Jay


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## JayinMI

I'm looking at using an Arduino for this purpose. I can use a servo attached the volume knob on a BitOne, and the PWM output to control the servo. 

Jay


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## Hextall 27

JayinMI said:


> I'm looking at using an Arduino for this purpose. I can use a servo attached the volume knob on a BitOne, and the PWM output to control the servo.
> 
> Jay


Would love to hear more about how to do that!! Jay have you scene the pics of how Scott Buwalda had his BitOne DRC modded by JK Labs for this purpose?

I have been struggling with the the whole how to integrate a tablet with a BitOne.1 
I thought of using a powered USB hub. I think it would allow the audio out as well as charging the tablet but I'm not sure. The 30 pin from the tablet would go to the main input, then I would plug in the CarJoy steering wheel control into port 1 and the Halide Bridge (delivers S/PDIF out) to port 2. Any problems anyone sees with using this and doing it that way?


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## emilime75

There's 2 possible solutions I see here, maybe 3...

1.  The car came equipped with a Bluetooth streaming capability, which many new cars have these days and they're controlling the Tab through the Bluetooth. They may also be getting the audio that way.

2. The stock head unit is still installed in the car, maybe relocated or pushed further back in the dash with the Tab installed in front of it. The audio could be spliced in to factory system either using the headphone out jack on the Tab or using a break out cable to go from the Samsung dock connector to RCA's.

3. Does the GTab have an IR receiver? Is there a remote control for it? I'm not sure, but if it has the ability to be controlled via IR remote, a PAC SWI-X should work to control it.

As far as line level audio outs on the GTab, I think I answered that in part 2 above.

It does appear that the control they have of the Gtab installed in that car is limited to volume, and maybe pause/unpause, but no track up/down. 




audionublet said:


> I've come across this video Galaxy Tab in car - YouTube
> 
> I'm trying to figure out how exactly how this is being done. I'm interested in putting the new Galaxy Tab 7.7 in my dash, but really don't want to use an external volume knob.
> 
> Also, AFAIK the G-tab lacks any type of line-level audio outputs, what are people using for this?
> 
> I'm scratching my head on how this is done...lol. I've posted this on MP3car and no real response yet.
> 
> Links are appreciated!


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## JayinMI

Hextall 27 said:


> Would love to hear more about how to do that!! Jay have you scene the pics of how Scott Buwalda had his BitOne DRC modded by JK Labs for this purpose?
> 
> I have been struggling with the the whole how to integrate a tablet with a BitOne.1
> I thought of using a powered USB hub. I think it would allow the audio out as well as charging the tablet but I'm not sure. The 30 pin from the tablet would go to the main input, then I would plug in the CarJoy steering wheel control into port 1 and the Halide Bridge (delivers S/PDIF out) to port 2. Any problems anyone sees with using this and doing it that way?



I actually just saw Scotts Bit Zero the other day (online) after a friend pointed it out to me. I found it amusing I was doing something so similar w/o ever hearing about his. LOL

So far, things are going reasonably well. I used an Arduino Uno to intercept the SWC wire going in to the radio, it then converts the analog voltage into a value (0-1023). Then I wrote some simple software that looks to see if the values line up with the ones I get from Vol Up, Vol Dn, or Mode. If it does it just says "Vol Up" "Vol Dn" or "Mode" on my computer (until I proceed further), and if not it triggers a relay that completes the circuit and allows the voltage from the steering wheel to go on to the radio.

I've also done some research, and instead of using a servo to turn the volume knob on the B1 I am just going to remove the rotary encoder from the board and simulate it using 2 more outputs from the Uno.

I used a 7812 voltage regulator to regulate the voltage from the car to a level the Uno can work with.

Got the circuit built, but have to test it yet....probably later today.

As far as interfacing with a tablet, I decided to keep my factory HU. Many of the Kia and Hyundai UVO radios are used with an amplified system, and have S/PDIF outputs built in. I plan to use a Toslink transmitter to send an optical signal to the B1.

When I was looking at GTabs and stuff, I saw people using HDMI to Toslink adapters and modified docks.

Jay


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