MMI style rotary encoder install - details

**Tony G** · 08-19-2005, 10:48 AM

This is the solution I have been using for the last 18 months, and I would like to share more information on what is a very reliable and flexible solution. (Installed in an Audi coupe).

Also my apologies for "dipping in" to some previous discussions and not following it up with detail.

Background:

What I wanted was an encoder that could be used in all situations e.g. menus, audio/video scrubbing, navigation zooming etc - think audi A8 MMI

I looked at the powermate but it all looked too "locked down" in terms of what comes out of the box. For my install it was also a little too large...

The solution came with the girder "mouse" plugin by J Hind. This allows the scroll-wheel and buttons to take on different roles such as cursor up.

So, you buy a mouse with a scroll wheel. You buy an alps 3 pin encoder that can be panel mounted. You remove the cheap and fragile 3 pin scroll-wheel encoder inside the mouse, and solder a cable to your panel mounted alps encoder. The encoder has indents, so each "notch" equates to a new line say in a dialogue box.

For mounting, I stripped a cigar lighter for an illuminated "collar" with LEDs and mounted this in an audi TT alloy collar (used for the 5 round switches).

Details:

Encoder -

ALPS STEC11B series - RS components (RSWWW.COM) part number 265-2930. If it doesn't work quite right in both directions, don't panic: swap one of the centre and outside pins.

Control Knob - from broken Audi "Symphony" head unit. Fits the APLS shaft very nicely.

LEDS - 5 LEDs provide even illumination at night. I have 4 * connected to the PC "on" output, and 1* connected to my startup PIC unit, which flashes in various states, but is on when fully booted. I like this extra feature!

Mouse modification/Girder plugin.

I bought a 4 button mouse, which allowed me to hard wire three "soft switches" i.e. menu specific, plus the "enter/select" switch of the alps. All these functions can be setup using the mouse plugin by J Hind. Get into enabling and diabling groups within girder and you have a set of controls you can "repurpose" for each application.

Functional examples

In Music/movie mode
Default rotary = scrub up/down timeline
Soft switch 1: Select artist/film (rotary becomes up/down menu)
Soft switch 2: Select track (as above)
Soft switch 3: Eq select (as above)

In navigation mode
Default rotary = zoom in/out
Soft switch 1: Select route (rotary becomes up/down menu) - scans any route on SD card reader
Soft switch 2: "Find nearest" (rotary takes through the various pushpins)
Soft switch 3: Display type (rotary becomes up/down menu)

All told it took about 4 hours to make, 3 hours to wire (and about 4 months to figure!)

More details and tips:

Use the ALPS encoder to replace scroll-wheel encoder NOT X/Y encoders on mouse board.

I have used 3*illuminated switches ABOVE the encoder knob - for me, this is more ergonomic than the audi MMI solution, which places 2 * switches above, and 2 * below the encoder. The switches are round "tactile" illuminated switches which protrude though a bevelled hole. I bought them from RS.

The illumination of the three switches are hard-wired to the "num-lock" "scroll-lock" "caps lock" LED output of a keyboard (you could use other methods such as USB i/o boards). WHY? depending on the menu / sub-menu you are in, only the viable switch options are illuminated. Slight overkill, but looks very slick.

The encoder is a switched version, which provides a good way to confirm selection. Hard-wire to one of the mouse buttons, again controLled by the girder mouse plugin.

Placing the encoder where Audi and BMW place theirs IS very comfortable.

Encoders and soft switches is better than a touch screen. Why?
1) you get used to the position of the encoders and switches so that you can often navigate without looking at the screen.
2) have you tried reading a touchscreen after a week of use? all the thumbprints in sunlight really affect the clarity. Too much cleaning makes for a shiny screen too..

Use Girder! - apologies to any front-end writers are coding for modified mouse boards!

**Scouse Monkey** · 08-19-2005, 10:59 AM

OMG Tony you legend. i have been wanting more info on how you did this and how you have yours setup is pretty much how the idrive is being setup (when dancehaven and i get round to working on it).

The nav zoom and scroll up/down is what I have planned. Unfortunatley the alps encoder I want is only available in the US - it has the added benefit of an 8-way joystick which requires a PIC to get it to work - although i am sure we could do it by hacking a mouse and keyboard. But DH wants to do fancy stuff with the lighting so that really does need a PIC.

**Scouse Monkey** · 08-19-2005, 11:07 AM

Tony, it might be possible to work on a 'widget' to display the functions off the soft buttons on the screen. Would be nice for those forgetful moments and could be alwasys on screen or activated by a 4th button or whn you start using the controller - ie sense the mouse scroll.

**Tony G** · 08-19-2005, 12:04 PM

Hi SM,

Agree. With many screens and menus, you need to know what the encoder and switches are doing.

Within girder, I use 3 OSD plugins. These either present a full screen (HTMLOSD) or an "overlay" screen (XPOSD) which is perfect for sitting on top of the MS menu in mappoint and Winamp albumlist. In this way, you never see a MS/ XP menu. In addition, I use DVD-spy plugin to overlay what music is playing, even when in the navigation screens. In this way, you are not having to "play" with the controlds too often.

When I change control mode, say from navigation to media, I use a third "pop-up" OSD that shows what the buttons and encoder do (this lasts for about 4 seconds).

I have attached some demo screens of how this looks. These are not actual screen shots, but some of the master bitmaps - some of the overlays and full screens are missing but hopefully shows the final "feel".

**aec merlin** · 08-19-2005, 12:13 PM

What mouse did you use? Did it have a mechanical wheel encoder or an optical one?

Can you post PCB pics?

**LESLIEx317537** · 08-19-2005, 12:38 PM

Very cool. Seems like a job, but well worth it once its going. I like the red LED glow.

**Quattro** · 08-19-2005, 12:48 PM

Wow, great work.
I would love to have something similar in my car as well, but I don't have any space to put it.

**Tony G** · 08-19-2005, 01:33 PM

@aec merlin

As you substitute the scroll wheel encoder it doesn't matter. I used a mechanical 4 switch (3 soft + 1 for the encoder switch) as it was cheap.

I haven't taken shots of this, but take out the scroll-wheel encoder - and its a 3 wire-for-wire replacement. Let me know if I can help any more.

@quattro
Most A4s have a tidy area next to the handbrake (mk 1,2 and new I think). It has removable panels (for either drinks holders or blank) which makes it nice to modify.

Is this space available on yours?

**Danceheaven** · 08-20-2005, 06:16 AM

Originally Posted by Scouse Monkey

OMG Tony you legend. i have been wanting more info on how you did this and how you have yours setup is pretty much how the idrive is being setup (when dancehaven and i get round to working on it).

The nav zoom and scroll up/down is what I have planned. Unfortunatley the alps encoder I want is only available in the US - it has the added benefit of an 8-way joystick which requires a PIC to get it to work - although i am sure we could do it by hacking a mouse and keyboard. But DH wants to do fancy stuff with the lighting so that really does need a PIC.

Well my pic skills are flying along scouse so its only a matter of time

Great job Tony im very impressed, thats a very professional finish plus i like

your use of parts from other audis i.e the knob and surrounds etc

You pics resemble how i visualise mine and scouses work to look

**Quattro** · 08-20-2005, 08:30 AM

Originally Posted by Tony G

@quattro
Most A4s have a tidy area next to the handbrake (mk 1,2 and new I think). It has removable panels (for either drinks holders or blank) which makes it nice to modify.

Is this space available on yours?

Yes there is space there, I current put my cell phone in that spot. But that space is not the best, its hard to reach, you have to angle you hand back, especially when the arm rest is down, which for me is all the time.

Thread: MMI style rotary encoder install - details

LinkBack

Thread Tools

Search Thread

Display

MMI style rotary encoder install - details and photos

Bookmarks

Bookmarks

Posting Permissions