356driver

I'm not sure the head unit has to know about the foreign device. If the device is able to make a connection directly to the BOSE amplifier (and knows the data streaming format) then it should be able to operate independent of the head unit.

I'm browsing the MOST spec that I downloaded from the OASIS site. Seems like a device is *supposed* to be able to come online, request a network address and a connection, even dynamically. Is this one of those unkept promises you were referring to?

ltc

OK, so let's say that you do introduce a device onto the ring and it does connect, even in bypass mode, so data is simply transferred thru the device.
Now, let's assume that the device is the highly sought after "iPod interface" adapter. How does one alter the user interface (hard or soft buttons) on the bus master/headunit/human interface device in order to control the newly introduced device?
If the device (and it's specifications/characteristics) were not known at the time that the code was written in the aforementioned headunit/bus master, then it will simply sit there on the ring, connected yes, but not fully functional.

As for connecting to the BOSE amplifier (now THAT is an interesting story in itself), as you read the MOST specification (and assuming you don't start foaming at the mouth and start to have seizures), you will come across ID's, addressing, etc... which just adds yet another layer of confusion to the whole MOST thing.


There are lots of silly little secrets behind most technology devices, MOST is no exception.
A long time ago, in a S/W revision far, far away, if you did introduce a device into the ring, the headunit would have assumed it was a CDChanger and had the appropriate code available.....sort of PnP.
So, if you did design a neat little "analog line level aux input" device...say for an iPod, designed in such a way as to emulate a CDC-4, then you could control the iPod from the headunit, which would think the whole time it was a CDChanger.
Of course, that is no longer the case, but it was fun while it lasted.

MOST is MOST, it is what it is, it (sort of) does what it was promised to do back at its inception, it is what each individual OEM wants it to be. It could be much more than that, but again, each implementation is the property of the individual OEM.

Best of luck on your research into MOST....remember, you were warned about the impending seizures and foaming at the mouth........

mudman2

Lewis

Sorry to jump on this again with a follow up. From what I got from Denision, they still intend to emulate the changer and use the headunit CD controls to handle the iPod.

Are you saying that this has been nixt by a software revision ? Or will the emulation approach still work if it quacks like a duck.

I know of no such update.

ltc

Michael,
The update was buried into one of the 'no audio' S/W releases. The fix was to either replace the amp or update F/W via CD update thru the headunit.

With respect to emulation, it depends on what you consider 'still quack'.

The CDChanger protocol has all sorts of odd behaviors (fixed length strings, assumptions on # of CD's which must be in the cassette, etc) which don't work well with an iPod.
So, if you are only looking to be able to control the iPod with track forward, track back, pause and not expect to get back information for display onto the headunit, then it can be made to work.
Of course, you will have to sacrafice your CDChanger, as this approach won't support both a Denisonusa device AND a CDChanger simultaneously.
As I have never seen their device, I don't know what they are attempting to provide for information back from the iPod, if any.
Controls are one thing, displays (and their format restrictions) are another.

If they are granted access to certain MOST protocol extentions, then they will be able to do more than if they simply have to "quack" like a CDChanger.

mudman2

Thanks Lewis, I sort of guessed that, the update through me a bit tho'.

I think if Denision had something they would have it on the street by now, as it is its always a couple of months away, which as we know in SW Developer speak for sometime never.

I find it interesting that for the 06 they are throwing mp3 read into the mix rather than an interface to an external device. I guess it must cost mucho R & D $ to develop into this version of the concept. However they must have extended the headunit dispay capacity to handle MP3 track text from the cd.

I am OK with my set up for now so I guess we'll see.

ltc

Michael,
If I were a betting man, my guess is that the issue with Denisonusa is not S/W, rather MOST certification/compliance testing.

The MOST cooperation, like Apple with their iPod, require that any (licensed) product be submitted for review and/or certification testing. Becker is the big dog, so they usually run/supervise the tests (which can be interesting when a company is competing with them in the audio product segment....no names please)

There have been those who pass first time with flying colors (no names please) while others (BIG name companies, Japanese, whose name can be seen prominently on an F1 team/car) fail miserably.

My guess is that's what's happened, so they are in the midst of a H/W redesign; most likely a relayout of their PCB.

Of course, if Denisonusa had deep enough pockets, they could hire a genius and avoid all of this unnecessary cost and delays

Give them time, I believe they may actually have something (it's not that hard what they are trying to do); they just have to learn to walk before they run in the arena of MOST.

ltc

The CGT headunit (from Becker, who else) is the basis for the MP3 offering IIRC.
The technical aspects to interfacing to an iPod are trivial, it is the legal/licensing issues which take longer.
You will begin to see iPod integration in German OEM offerings fairly soon.

Cupcar#12

i am betting we will see a BMW-esq iPod intigration with becker products soon, since they are owned by H/K whom i believe make the BMW OEM units.
nice $900.00 option for porsche to sell (which i would purchase interesting enough if offered)
always an interesting discussion

356driver

Lewis (and Michael),

Sorry not to be here for the last couple of days. We've been hosting developer seminars so I've been away. Interesting discussion so far. But there is a lot of emphasis on the head unit somehow controlling the device. I'm not sure if you want to go for this level of integration.

An advanced integration would have your portable device (iPod or XM radio) join of the network and be controlled by the head unit. Through its user interface the head unit would allow you to select stations or tracks, or playlists or whatever. Certainly this is an elegant solution but challenging in three ways. First it would be far more trouble than its worth to hack into the head unit firmware to add a new user interface. Second, spoofing a CD changer is not a terribly realistic way to integrate anything other than another CD changer into the network due to the specifics of MOST CDChanger protocol. Third, even if you are able to overcome all this, your magic adapter would have to be able to externally control your portable device based on inputs from the head unit's user interface and virtually the only way to do this is through an IR remote control port - and we all know how easy it is to adapt "universal remotes" to our TV sets at home. In any case I suggest leaving the head unit user interface completely out of the picture.

A more basic integration would be limited to getting your portable device into the ring and producing sound through the amplifier/speakers. The adapter would register with the network, find the address of the amplifier, connect with the amplifier, and stream data to it. Period. Either the amplifier accepts a connection from anything it views as a legitimate source and processes its packets. Or the adapter intercepts packets from a legitimate source (i.e., the head unit's tuner) throws the tuner's packets in the bit bucket, and forwards its own packets.

There would be no external control of the iPod or XM radio. We would still control our iPod or XM radio through its own user interface. This is what we do today. The portable device would connect to the MOST adapter through its headphone output. This would make the adapter universal to almost any portable device. The benefit would be better sound through your expensive BOSE stereo system.

Would anyone be interested in this less elegant solution? I dunno - I'd pay a little bit of money to get better sound than is achievable with a wimpy FM modulator.

mudman2

I can't argue with that, I like the UI on the iPod. It would be nice.

ltc

356driver,
As you seem to have locked onto this (why, I have no idea), here is your solution (as was discussed back in the good old days before I bought my Cayenne.....18 months ago):


Step0: Go buy one of these (OptoLyzer....standard one, upper left picture:
http://www.oasis.de/eng/content/view/86/112/
http://www.oasis.de/eng/content/view/322/348/
http://www.oasis.de/files/networkana...5v0_5V0-01.pdf

Step1: Connect iPod audio output (I would suggest using the line level 1VRMS outputs from the botttom connector of the iPod rather than the headphone jack) to the Audio Inputs of the Optolyzer. The iPod line level audio outputs are available from the rear jack of a iPod mini docking station (std apple accessory).
Your audio inputs you wanted are listed on page 20 of 28 in the manual (pdf file above)

Step2: Connect OptoLyzer to the ring, say in place of the CDChanger, using the factory supplied optical harness (making your own is a bit difficult with polishing fiber, connector housings, etc).

Step3: Write some simple scripting code to "Connect" using the scripting tools provided wtih the Optolyzer. Once you're connected, you're all set.

Step4: Run this "OCI file" via a laptop....or better yet a PalmPC, Pocket PC....anything with a RS232 serial port (which connects to the Optolyzer).

Step5: Press 'Play' on your iPod

Step6: Enjoy.

P.S. No charge.

ltc

Not true.
iPods have a serial protocol which allows for remote control functions (iPod aftermarket accessories take advantage of this fact.....a google search will lead you to some hack sites which have reverse engineered this). apple designed a fairly robust back door port into the H/W (analog and digital)

The 'adapter' you described would simply have to convert commands transmitted over MOST (CDChanger protocol or something else) into a serial protocol (UART based) into the iPod. This would allow for simple remote functions (play/pause, track forward, track back) via std headunit controls.

356driver

You are right. I looked at some of the hacks which require opening the case to access the serial lines. It also looks like there is an external serial port on the latest iPods. So external control looks feasible for iPods, but probably not for many other portable devices.

ltc

Not necessary to open the case. Serial port/UART connections are available at the bottom connector of all iPods (except iPod shuffle, which is USB only)