tea4two

Hi to all,

I've searched to all forums information on how works "Wired Remote" input of pioneer Car audio (seems that Sony use a similar protocol).

I know that the connection use a 3,5 mm jack stereo connected to KEYD, KEYAD and GND, inside the car audio unit.

The wired remote control recognize resistors, It's a serial protocol or use other kind of code ?

I would want to control the Unit using a PC so I need to know this infomration to make the right interface.

Thanks in advance

2k1Toaster

Usually when you press buttons, a unique resistance is applied to the input voltage of the controller. What gets sent out is the "data" so to say.

No two buttons produce the same resistance when pressed. So your device must simply change the resistance.

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tea4two

So pioneer Wired Remote Input use a resistors code to control Volume, Scan, etc... ?

Do you know right values for every command ?

How this resistors must be connected ?
GND + KEYD (for some controls like volume, mute...)
GND + KEYAD (for other controls scan, band...)

Thanks for your fast response!!!

vic_c

Hi, tea4two - did you get this working, or find out any more - I am looking for the same information. I believe the wired remote device CD-MR70 is compatible but I am not convinced that only simple resistance values are needed to drive these inputs. There is a pioneer adaptor CA-R-PI.181 that accepts various switch inputs and procides a control signal onto the 3.5mm jack but I have so far been unable to discover what form that control signal takes.

tea4two

I don't know how works pioneer remote control.
I need this information too.
I've created this thread to obtain this informations.

2k1toaster tell us that pioneer uses resistors switch, this information seems right,in fact i've found third part commercial adapters(interfaces) that share sony/pioneer car audio.
And i've found too that sony use resistors switch at least in old car audio.

I haven't other informations....

Please who know more info reply to this post

Regards.

vic_c

OK, I've now had some time to play with a Pioneer DEH-2800MP. I found a reference elsewhere that suggested that the Sony hard-wired remote uses the following resistance values:
0 Ω Off
2.2k Ω Source
4.4k Ω Mute
6.6k Ω List(Disp)
8.8k Ω Seek up
12.1k Ω Seek down
16.8k Ω Volume up
23.6k Ω Volume down
33.6k Ω Select
48.6k Ω Mode

This works out nicely as a series resistor chain as follows:
2.2K + 2.2K + 2.2K +2.2K + 3.3K + 4.7K + 6.8K + 10K + 15K
all nice E12 range values. These are the exact values I have found
reported elsewhere in a Sony RM-X2S wired remote device.

When I hooked this up to the tip of the remote conector jack on the Pioneer
I found the following functions seemed to work:

0 Ω Off (No apparent effect)
2.2k Ω Source (switch between CD and radio or OFF if > 2 seconds)
4.4k Ω Mute (toggles "ATT" on display with muted audio)
6.6k Ω List(Disp) (No apparent effect)
8.8k Ω Seek up (Search up-radio or next CD track - hold down to fast forward.)
12.1k Ω Seek down (Search down-radio or previous CD track)
16.8k Ω Volume up (Volume up)
23.6k Ω Volume down (Volume down)
33.6k Ω Select (No apparent effect)
48.6k Ω Mode (In radio mode switch between FM1,FM2 and MW.)

Haven't managed to get any effect on the ring connection of the remote jack
both tip and ring appear to be tied up to 5v tip (STRKEY1, pin 80 on PE5518A)
ring (STRKEY2, pin 47 on PE5518A).

Connecting various resistances between tip and ground of remote jack effectively pull STRKEY1 down to different voltages to trigger the remote control.

Anyone know what STRKEY2 is supposed to do?

vic_c

I think I have figured out the function of STRKEY2, pin 47 (KEYAD):
When kept at 5v all the functions for KEYD are as mentioned above but if KEYAD is pulled down (below about 2.4v) the the function of the seek up and seek down are changed to select the next/previous pre-programmed tuning stored for the current selected radio band.

All I have to do now is build the cct to interface with the steering stalk switches.

jaymezb

Hi, i have a DEH-2800MP and a control stick with 4 switches which i would like to map as follows:

switch, function
1, volume up
2, seek foward
3, volume down
4, seek backward

How could i do this?

jaymezb

I just went and tested the steering stalk with a mulit-meter and it is simply a 4 way switch with an input.

So do i simply supply the switch with the 12v accessory supply (blue wire supplying 300mA 12v DC) and put a resistor in series of the value you so kindly worked out for the function desired ?

Is this signal then applied directly to the unit? which pins do i use on the 3.5mm jack?

tommo_79

Are there any programs that can read these resistance values through a com port (or any other port) to control functions on a pc? Such as winamp functions or keyboard strokes?

2k1Toaster

That's the plan. I don't know if it would be easier to build logic to interface with a custom keyboard circuit, or directly with the serial port.

You cannot send resistive values down a serial line by simp-ly sending the raw data. It is either high or low. 3.3v is the threshold i think. (Been a while since I messed with the serial port!). So if you send a 4v, and 4.2v and 4.4v it is all interpretted as a logic high ("1").

So you will need to convert that analogue signal into a digital stream and send it in synchronously. It could be quite a bit of work. If you have a PIC programmer, then the job could be a lot easier. It might even be worth getting an el-cheapo PIC programmer second hand or eBay or something, and coding it. You could always sell it on ebay once you're done with it.

That way it is more software coding than hardware wiring.

To communicate with the keyboard circuit, it would need to be something along the same lines, but the interpretation will be harder. With software you can say from value 1 to value 2, make it equal button 1. Hardware, you need to do that will be a comparator circuit between the input and both value 1 and value 2. If both less than value 2 and greater than value 1, then button 1. Lot's more chips if you don't have a PIC!

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Ray2k

Hi, first post here and I know it was posted 6 months ago but just wanted to say how useful this thread has been! I'm going to be creating a wired remote control out of my 14 year old tape player (using the buttons on the front of it) to control a new pioneer DEH-2920MP mounted out of sight in the glovebox, to deter the thieving scum round here who stole my last lot .
I've just been and tested the resistor chain mentioned (on a DEH-2920MP) and it's all spot on, but I'll fill in one of the gaps:

This changes the display - in (FM) radio mode it changes between frequency, station name (from RDS) and station type (also from RDS), and in CD mode with an mp3 CD in it switches through various info including track title, artist name, file name, folder name and a few more. I couldn't see any effect for 33.6k either.

Anyway thanks.

Ray

evdokimosk

Is it possible for someone who tried it to explain the connection of the two signals KEYAD and KEYD.

How this resistors must be connected ?
GND + KEYD (for some controls like volume, mute...)
GND + KEYAD (for other controls scan, band...)

FordNoMore

Just wanted to add that (at least on my Pioneer deck) the resistance values appear to be "maximums" more or less... For instance, any resistance from about 6.8k - 8.8k connected between the tip and sleeve seems to work as "Seek Up". At about 9.0k it's unpredictable, and from about 9.2k up it begins treating it as "Seek Down". So err on the low side of resistor values!

Also, I'll vouch that my Pioneer Premier DEH-P860MP works as described above.

FordNoMore

To clarify things a little: All resistor values listed above are to be connected between the tip and sleeve of the 1/8" plug (stereo headphone plug). Apparently the only use for the ring is that if you connect it to the sleeve the "Seek" buttons cycle through radio preset stations rather than directly tuning. Do NOT connect 12V to anything!!!