How does iPhone headphone remote circuit work?

[wiichkin]

I think the answer lies in Figure 6 - basic circuit.

I also have the same goal as the original poster, to integrate iphone remote control into a giro helmet. However, I don't see a reason why the whole remote has to be recreated from stratch. Rather, I will wire up the remote to the chin strap to use it as a mike and will create a control circuit like in Fig 6 with large buttons elsewhere on the helmet.

we'll see how it goes.

 

[pcmofo]

Finally I have solved the problem!

After taking another swing at finding something I could wire together I have finally found a product that is exactly what I wanted in the first place.

Smith just released a cable compatible with the iPhone this season 10/11 but I never saw it because I have a Giro helmet.....

http://www.amazon.com/Skullcandy-Si...HZPK/ref=sr_1_1?ie=UTF8&qid=1297548101&sr=8-1

Its a single cable that plugs into the iPhone with a 4 conductor jack and is fully compatible with the remote functions like FF and RR as well as the voice command and mic functions.

The other end is a female 3 conductor cable compatible with the existing headphones wired in my helmet (also made by skull candy)

It even has a volume control! Its analog so its more reliable than the digital one, toggling the buttons and hitting the correct one.

Now for the bad news....

I tested it out at home and it worked great. On the slopes was a different story however. Sometimes the button did not work and required me to either unplug and replug the cable to the iPhone, or to shield the mic/button from the cold/wind to get it to work again.

Also, when talking from iPhone to iPhone, both people using the same mic/headset their were issues.

I suspect a poor build quality for the electronics as main issue due to the cold. The volume in the white headset is dependent on resistance/capacitance to send a signal to the iphone. I suspect the cold is effecting this quality as, after close observance, I find that pressing the button, when cold, causes the volume to adjust slightly down instead of play/pause, the original issue I had with it not working well.

Overall, it works better than any other existing solution as their is no other solution I know of. Unfortunately, it is $50 with the headphones for a Smith helmet, which I did not need, and if you need Giro headphones you will have to make these fit or buy them separately.

Skull candy makes these for Smith only right now, but also makes headsets for Giro, why they dont have this exact model is beyond me, but maybe that will change.

For now I am sticking it out with the Single-Shot, until someone comes up with something better. Hopefully someone will find this info useful as it took over a year for someone to build this product.

 

[jsoundz]

Quick question!

Ok so i'm in the same boat as you guys. right now i have a "throat mic" set up that i want to modify for my iphone. I know that its near impossible to replicate the volume controls, but for the center button, could i just replicate it by simply shorting the mic to common/gnd?

here is the product i have in mind:

http://www.dealextreme.com/p/3-5mm-...-acoustic-tube-earphone-mic-for-kenwood-71827

The headset has a push to talk button, which i could rewire to short the mic to ground. I hope this would work, please confirm.

 

[pcmofo]

Ok so i'm in the same boat as you guys. right now i have a "throat mic" set up that i want to modify for my iphone. I know that its near impossible to replicate the volume controls, but for the center button, could i just replicate it by simply shorting the mic to common/gnd?

here is the product i have in mind:

http://www.dealextreme.com/p/3-5mm-...-acoustic-tube-earphone-mic-for-kenwood-71827

The headset has a push to talk button, which i could rewire to short the mic to ground. I hope this would work, please confirm.

You must not have read this entire thread as all the answers you need are in here...

You NEED to have an apple approved accessory headset in order to do ANYTHING with the microphone. It has a chip which sends a code when you plug it in. Their are no other options, hacks etc, with the exception of building your own chip which will simulate this code. This is not only complex but also not ideal as you would need a separate power source.

Putting all of that stuff aside.... it *could* be done with the mic you listed... IF you hack an iPhone headset and splice it into the one you want. Again I say *could* because in order for it to work with the mic in the headset you have to make some solder connections that most likely wont work well if at all, and you will have to hope the POS $20 mic you are buying works well in the first place.

If you REALLY want a iPhone compatible throat mic.... suck it up and buy one thats designed to work with the iPhone... otherwise you are undertaking a task that will cost you much more in both time and money and have a high chance of failure.

http://www.thinkgeek.com/electronics/cell-phone/c8e1/

 

[RYVAL]

I built the fig.6 circuit outside the apple headphone using raw components just to replicate the system. None of the features worked like the OEM apple mic, simply shorting the two wires did nothing and doing either of the vol+ or vol- made the volume slider skip to 75% full for as long as I held the toggle button. The fact that I got it to do something amazed me.

I didn't have any sort of speakers in the circuit (to emulate the headphones) but I doubt that the absence of those would mean anything.

I'm looking at replicating this for use in a vehicle, replacing the factory head unit with an ipad2 to send signal out to the external factory amplifier. I have 4 years of vehicle electronics experience so all that is left is to get this headphone control circuit working to retain the steering wheel controls. If there's no other way I might have to revert to continuing to use the OEM apple headphone cable and wiring up the steering wheel buttons to do continuity like pressing the apple buttons do.

I really wish that this were possible through the dock connector.

 

[ChicagoApple]

TRRS Connector.

You should read up about the TRRS connectors on wikipedia. That may answer some of your questions about how the microphone on the headphones work.

The Apple buttoned earbuds work so great with the iPod Touch, iPad, and iPhone, that I got 4 of them. Of course iPad 1 does not have a microphone, but the earbud's buttons still work.

 

[vincent vaughan]

play/pause with a foot pedal

Hello everyone

So glad I stumbled over this thread by accident....sounds great.

Ideally I would like to use my iphone/Ipod to play backing tracks while gigging but would really need the ability to start / stop the track using a foot pedal thus making the unit 'handsfree' so to speak
Is it possible to configure the wiring to do this.

I dont need the microphone..........just the audio 'out', play/pause and forward / back would be a big bonus if connected to seperate pedals....

Any help, advise etc would be really appreciated

Regards

Vincent

 

[ben-r]

You guys have seen this product right? LINK

 

[cirrussk]

Any updates to this thread? I wanted to build my own connection to the iDevice for volume control only ... trying to figure out how to build the circuit just to control that??

 

[Varun Maitreya]

This is how a TRRS socket looks like and 3 pins for mic which clearly indicates about vol+ vol- and mic. And single gnd and right and left. There must be a forward and reverse biasing diodes and some pulse with modulation going on.
This is how I made a TRS to TRRS converter for my old lappie. https://docs.google.com/document/d/1Tany6Q6xV70B5HR9JH_fcntLbQ_4ZZJt02UZxStyDf4/mobilebasic

 

[bblpete]

OK so I took a look with the multimeter. According to the pinout I linked to, pin 4 is microphone + and pin 3 is Ground. When you press the play/pause/skip/back button on the remote it simply shorts these two pins together. Obviously this must be done before the microphone. I detected a 1.8-2.0 ohm resistance when pressing the button. This may just be the resistance in the line or it could be a very small resistor to prevent damage from shorting out the wires.... not sure yet... either way it would be super easy to recreate this effect by just adding a button connecting pins 3 and 4.

I have a Giro headphone cord that came with my helmet that connects to a cellphone. I can rewire it to provide the iPhone functionality but this still does not solve the more difficult problem of how the + - volume buttons work...

On the official headphones the mic/buttons are on the Right earphone line. This means it is very likely that the buttons only interact with the mic+ and ground (pins 3, 4) in some way. We know that the center button shorts out the pins. the + - buttons must send some type of signal. As I said before the "circuit" is unpowered so it must be some type of resistor etc.

I was unable to detect any resistance value by testing the pins and pressing the + - button as I was able to do with the center button. When I set my multimeter to the diode setting, I got back a voltage reading. I have no idea what this means as I have never used this feature of my multimeter before but when I pressed either + - button I got back a consistent voltage result.

As soon as I talk to my electrical engineering friend to figure out what this means I will attempt to recreate everything on a bread board as a prototype/proof of concept. If anyone has any idea or suggestion as to what this might be please let me know.

[doublepost=1455519317][/doublepost]

OK so I took a look with the multimeter. According to the pinout I linked to, pin 4 is microphone + and pin 3 is Ground. When you press the play/pause/skip/back button on the remote it simply shorts these two pins together. Obviously this must be done before the microphone. I detected a 1.8-2.0 ohm resistance when pressing the button. This may just be the resistance in the line or it could be a very small resistor to prevent damage from shorting out the wires.... not sure yet... either way it would be super easy to recreate this effect by just adding a button connecting pins 3 and 4.

I have a Giro headphone cord that came with my helmet that connects to a cellphone. I can rewire it to provide the iPhone functionality but this still does not solve the more difficult problem of how the + - volume buttons work...

On the official headphones the mic/buttons are on the Right earphone line. This means it is very likely that the buttons only interact with the mic+ and ground (pins 3, 4) in some way. We know that the center button shorts out the pins. the + - buttons must send some type of signal. As I said before the "circuit" is unpowered so it must be some type of resistor etc.

I was unable to detect any resistance value by testing the pins and pressing the + - button as I was able to do with the center button. When I set my multimeter to the diode setting, I got back a voltage reading. I have no idea what this means as I have never used this feature of my multimeter before but when I pressed either + - button I got back a consistent voltage result.

As soon as I talk to my electrical engineering friend to figure out what this means I will attempt to recreate everything on a bread board as a prototype/proof of concept. If anyone has any idea or suggestion as to what this might be please let me know.