Steering Wheel Controls - Page 6

god_of_cpu · 09-28-2004, 04:49 PM

Quote: Originally Posted by Scarum

http://www.mp3car.com/vbulletin/atta...tid=2623&stc=1

OK, jumping in here at the end (and at the deep end), I would certainly like to preserve my steering wheel controls when I build the in car computer, however I haven't done circuits and just can't get my head around the diagram god of cpu has done.

If 5v is supplied by the gameport, what is the power node doing and where is it coming from? Where the nodes (the red dots) join, how is this done physically? Would you do so by soldering onto a PCB or by simple joining and soldering of wires?

See, I'm a noob extraordinaire!

Your probably just making this more complicated then it is... The hardest part should be figuring out which lines you need to tap into on your car. To connect them I just twisted the wire around the diodes and resistors then soldered them together, you really don't need a PCB, but you can use one. Theres a picture on the g35driver site that I posted that shows my completed wire.

You need to splice into 3 lines that your steering wheel controls use. One I call power, (it may actually be a ground in your car as it is in mine when it is connected to the head unit), One is remote control B, and the other is Remote Control A. The line called power does not supply any power, it recieves it from the joystick port.

If you want to retain use of your steering wheel controls with your stock headunit, you should look at my other circuit diagram with the relays in it.

Scarum · 10-01-2004, 02:36 AM

Cheers for clearing that up, I would not want to go down the relay road, no I know power is ground, all is clear

moahdib · 10-06-2004, 01:00 AM

What can I do with my 2004 Acura TL =) I have the wiring scanned I guess should be pretty easy, I just gotta give it a try.
Any thoughts CPU GOD?

Green(1) is the signal and Brown (2)is the Ground.

Here is my diagram...

I only have 1 wire and 1 ground from the steering remote buttons and total of 5 buttons. Do i have to connect to pin 6 on the joystick port for the extra button or would connecting to just pin 3 work ok?

If this works I'll owe you big time for all your excellent work =) I almost went and bought PacAudio SWI-X.

god_of_cpu · 10-06-2004, 08:49 AM

I'm not quite sure on how things are working in your car. Your best bet is to just go try a few things and post results. Your current diagram seems like a good place to start. To know if you have to hook up pin 6 of the joystick, connect your voltmeter to the two lines your currently planning on hooking up and see what happens to the resistance values when you hit the extra button, if it doesn't change, you'll ahve to add it to its own axis.

moahdib · 10-06-2004, 09:11 AM

Do I have to hook up the 5V power source to test this?

god_of_cpu · 10-06-2004, 09:46 AM

If your testing with a voltmeter and everything still connected to your headunit, the headunit will supply the power.

moahdib · 10-06-2004, 10:21 AM

hmmm I don't know if you look at the first pic above, I have a little table with the resistance values when each button is pressed. Each gives a different reading. I thought i needed to test with the steering wheel connections to the diode/resisitor and not to the radio.

god_of_cpu · 10-07-2004, 05:33 PM

Quote: Originally Posted by moahdib

hmmm I don't know if you look at the first pic above, I have a little table with the resistance values when each button is pressed. Each gives a different reading. I thought i needed to test with the steering wheel connections to the diode/resisitor and not to the radio.

I was thinking if your testing volts you need to have it hooked up to the radio, your right, if its just resistance you don't need to supply it power, just hook it up to the voltmeter.

moahdib · 10-07-2004, 06:27 PM

god of cpu... I noticed that your steering wheel control unit is not grounded internally like mine and others are. I have a ground connection both to the radio and somewhere inside the control switch it seems.

These steering controls, and including mine are grounded.
Lorenzo

another one from the nissan 2001 maxima

Perhaps that is why those could not work. I have not tried it on mine yet... I also need to figure out if changing the ground wire to 5V will screw up the the HFL ( Handsfreelink) buttons which are used for calling using my bluetooth phone, i'll probably have to rewire it.

What do you think??

Has anyone here gotten this to work with a USB gameport adapter as well? I don't have a game port on my car pc.

OriginalNick2 · 10-13-2004, 07:36 AM

cant a similar effect be achieved using the keyboard port on mobo? most of us willhave this redundant (assuming touchscreen!) and so why not be able to use wires from SWC to keyboard and program like that??

Is it possible?

god_of_cpu · 10-13-2004, 08:39 AM

Quote: Originally Posted by moahdib

god of cpu... I noticed that your steering wheel control unit is not grounded internally like mine and others are. I have a ground connection both to the radio and somewhere inside the control switch it seems.

These steering controls, and including mine are grounded.
Lorenzo

another one from the nissan 2001 maxima

I'm not sure what you mean... My car does supply an individual ground and then power through the lines for the buttons. I make this opposite when I hook up my steering wheel controls, supply power where the ground was and attach the ground to the control lines which i guess could be where the confusion is coming from.

Quote: Originally Posted by moahdib

Perhaps that is why those could not work. I have not tried it on mine yet... I also need to figure out if changing the ground wire to 5V will screw up the the HFL ( Handsfreelink) buttons which are used for calling using my bluetooth phone, i'll probably have to rewire it.

What do you think??

I have an Infiniti G35, (infiniti = nissan) the wiring for the steering wheel controls is almost exactly the same as those for the nissan 2001 maxima. If you can't get it to work on a maxima like that, I doubt it's because the steering wheel controls aren't compatible with the circuit.

If your handsfreelink buttons are on the same circuit as your other steering wheel buttons, then yes doing this will probably screw them up. If there not, then it doesn't really matter.

god_of_cpu · 10-13-2004, 08:57 AM

Quote: Originally Posted by OriginalNick2

cant a similar effect be achieved using the keyboard port on mobo? most of us willhave this redundant (assuming touchscreen!) and so why not be able to use wires from SWC to keyboard and program like that??

Is it possible?

I'm not familiar with how keyboards work, but I assume if your suggesting this, that they have a built in ADC that converts different resitance values into key presses. If so, its possible that could work out well, the problems I could see with doing something like this is in calibration. With the joystick port, the APIs available for windows expose the axis values which is a continous linear range of values that can be bound to a particular button press. With a keyboard, the only thing you can look for is button presses. If your lucky, this may work out well and you'll only see 1 keyboard key for every steering wheel button you press, but given my experiences with the steering wheel controls, I doubt this will be the case.

The resistance the ADC in the joystick port sees varies within a certain range over time with a single button press using the keyboard, I would think this would result in multiple different keys as being detected as pressed, and thats if your lucky and all the resistance values are in the range that are mapped to keyboard keys. At a minimum, do something like this, you would probably need to write a program that uses a global keyboard hook to tap into the keyboard keys and override them being sent to the other applications in windows. You would probably also have to map multiple keyboard keys detected to correspond to one action you want generated when one of them happens and like my joystick control program you'll probably also need to do alot of filtering so multiple key presses from a single button press aren't detected as multiple button presses.

Again, those are just my thoughts, I know nothing about keyboard ports, but it seems it potentially could work out well with a bit of work and be a much more universal solution.

moahdib · 10-13-2004, 10:32 AM

Quote: Originally Posted by god_of_cpu

If your handsfreelink buttons are on the same circuit as your other steering wheel buttons, then yes doing this will probably screw them up. If there not, then it doesn't really matter.

Yes, Ground is also connected to the handsfreelink buttons.
Perhaps a diode might solve the problem? I will be terribly upset if I have to remove the whole airbag system to install this thing!

OriginalNick2 · 10-13-2004, 01:51 PM

ok just wondering since most recent PS2 keyboards have volume and/or track keys on them and are fed by standard key board wire - keyboards have LED's on them so must also be recieving power (if thats a good thing?)
my point is most keyboards have designated keys for track skip and volume - so imagine cutting away the rest of your keyboard toleave only the relevant "media" keys - then take the wires from these and attach to SWC?? earthing all other wires or setting to mutual resistance / voltage may have to be achieved. Then just plug PS2 cable into keyboard port instead of using joystick,does this not sound feasable??

Nick

god_of_cpu · 10-13-2004, 02:02 PM

Quote: Originally Posted by OriginalNick2

ok just wondering since most recent PS2 keyboards have volume and/or track keys on them and are fed by standard key board wire - keyboards have LED's on them so must also be recieving power (if thats a good thing?)
my point is most keyboards have designated keys for track skip and volume - so imagine cutting away the rest of your keyboard toleave only the relevant "media" keys - then take the wires from these and attach to SWC?? earthing all other wires or setting to mutual resistance / voltage may have to be achieved. Then just plug PS2 cable into keyboard port instead of using joystick,does this not sound feasable??

Nick

I don't see how this could work. The steering wheel controls simply change the resistance of a constantly flowing current when you press a button, I don't see how this could work just by hooking it up to a specific key.

If a keyboard also works by varying resistance similar to how the SWC work. I.e. for each key you press, it varies the resistance of a constantly flowing current by a different amount, then tying the steering wheel controls into a specific key will not have the expected outcome. I'm not even sure how you could even wire it up like that, but if you just looped the steering wheel control wires in the keyboard wires it would apply the resistance of the steering wheel control button, not the resistance for the keyboard key. Something like this could work, if the steering wheel controls worked like toggle switches, physically disconnecting or connecting a line, but they do not. Errr... In a way they do work like toggles, but you would have to take apart your steering wheel and bypass the resistors in them and tie directly into the switch to achive this rather then just tapping into the lines going into the headunit.