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      02-17-2009, 11:51 AM   #45
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Quote:
Originally Posted by gasmeter View Post

I would design my own carrier board / processor / add can interface etc.
One question though, the can bus connections on the obd2 port, are they the same as the K bus and are the active in terms of listening for packets on the K bus and sending messages back ?
Ideally i'd like to start without tapping into the bus but simply using the diagnostics port as the hardware will be on and off like a yo-yo for along time .

Either way I am following this thread with keen interest.

Peter
No, OBDII is on its own bus.

I dont think that the steering wheel is even on the same bus as this discussion is referencing (KCAN). I think the standard multifunction is interfaced into the SZL (Steering column switch cluster) through the coil spring assembly. The SZL is on FCAN and PTCAN. The PTCAN is of note as I believe this is how the Performance wheel gets its data.

The signals from the buttons to the SZL are a simple construct of a voltage divider (to generate the button pressed) and voltage comparators (to "decode"). Now eventually the process, in some form, is pushed onto the KCAN by the JBE to the RAD/CCC. Its going to take some effort to localize these messages as it may not be a one-to-one packet event.


Here's a breakdown of the process

Path:

1) MF buttons -> SZL; --------------- No bus. Just simple voltage divider/comparator
2) SZL -> JBE; ----------------------- FCAN or PTCAN (probably FCAN)
3) JBE -> RAD/CCC; ------------------ KCAN
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      02-18-2009, 08:09 AM   #46
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Hi
Yes there certainly seems to be a lot of hopping between buses.
I did develop some CAN stuff over 10 yrs ago before can was mainstream but then it was only class A,B,C networks and BMW seem to have gone network mad !.

Looking around I have seen products from parrot that sit on the K can bus behind the radio and look for the steering wheel buttons, and also recently I have seen that products like the dension that sit on the most optical bus also seem to be able to access the steering wheel buttons (like answer phone) over the data channel of the most bus.


I hadn't see the bus structure docs before but i can see now for steering wheel controls

SZL-->FCan-->KCan

Also there is a phone button on Rad 2 which is on KCan (i'll ignore the Most), so probably the best place would be the KCan to tap into.
I do have the old codes for older BMW series so the message ids will be the same with luck.

I had 3 levels of targets really

1/ to be able to read the steering wheel buttons / phone / up down etc
2/ to be able to manually change the input on the Rad2 to aux (if its possible to define an input rather than cycle through available ones)
3/ to be able to display some info on the radio display

I guess access is the big problem, KCan is easy to get at as its at the back of the radio.

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      02-18-2009, 09:48 AM   #47
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Unfortunately, the old IBUS (KBUS based) application layer does not translate over to KCAN. If you have an E90, KCAN is most easily accessible (for debug/development) on the ultra-sonic motion detector module in the overhead.
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      02-18-2009, 01:29 PM   #48
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Hi

Ok I have got as far as selecting a processor to handle the comms side with an inbuilt can 2.0 controller (selected on the basic I already have a compiler and flash programmer for it), actually an NEC device.

http://www.eu.necel.com/micro/produc...ml#lineControl

Could I ask a couple of more questions

1/ With the ignition on but engine not started , is there a lot of traffic on the KCAN ?
2/ aside from the overhead alarm . (I assume its a alarm module and not just a sensor ?)
is there a bus point to pickup on in the boot (actually an e92) ?
3/ Is there anything in the centre console area ?

or where has everyone else tapped into the car ?

I am thinking of fitting a semi permanent connector so i can connect as and when I like but the ideal would be the boot or center console.


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      02-18-2009, 02:04 PM   #49
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Quote:
Originally Posted by gasmeter View Post
Hi

Ok I have got as far as selecting a processor to handle the comms side with an inbuilt can 2.0 controller (selected on the basic I already have a compiler and flash programmer for it), actually an NEC device.

http://www.eu.necel.com/micro/produc...ml#lineControl

Could I ask a couple of more questions

1/ With the ignition on but engine not started , is there a lot of traffic on the KCAN ?
2/ aside from the overhead alarm . (I assume its a alarm module and not just a sensor ?)
is there a bus point to pickup on in the boot (actually an e92) ?
3/ Is there anything in the centre console area ?

or where has everyone else tapped into the car ?

I am thinking of fitting a semi permanent connector so i can connect as and when I like but the ideal would be the boot or center console.


Peter
1. Yes. As soon as you unlock the vehicle, there is quite a bit of CAN traffic.
2. Maybe. On the E46 you could tap onto the IBUS through the CD changer, however that is now on a MOST bus, as are all the audio components. I'm not sure if there are any modules on KCAN back there. TCU maybe? Ill see if I can find something, as I would prefer that location for a permanent install.

3. Yes, but I dont remember the connector #. If you have Idrive it is connected, if you do not have Idrive it will be tucked away. Find the Idrive retrofit thread for details.

EDIT:

3. No. Looks like that cable is not pre-iwired. The harness is only installed if you have idrive.

"I-drive controller:
-Is hooked up via 4-pin cable which is non-existent on non-idrive cars - if we tap into the same pins (as above) for the CID, I think we can get it working also:
Pin 1 of the controller: 30G(power) ----> hook to pin 15 on back off CCC(x13812)
Pin 2 of the controller: 31E(ground) ---> hook to pin 12 on back of CCC(x13812)
Pin 3 of the controller: K-Can high -----> hook to pin 11 on back off CCC(x13812)
Pin 4 of the controller: K-Can low ------> hook to pin 9 on back off CCC(x13812)"
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      02-18-2009, 02:43 PM   #50
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Quote:
Originally Posted by gasmeter View Post
2/ to be able to manually change the input on the Rad2 to aux (if its possible to define an input rather than cycle through available ones)
I've been lurking on this interesting thread, but have not anything to contribute until now.

It is possible to force the AUX input active:
http://forums.e60.net/index.php?showtopic=51895

It is also likely that the AUX input can be selected using some CAN command. The BMW ACM appears to select the the AUX input via the CAN bus. More information about the ACM can be found on several threads in this forum:
http://forums.e60.net/index.php?showforum=22
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      02-19-2009, 03:08 AM   #51
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RAD 2 / mute etc

Thanks for the info
being able to change over to the aux using the mute button will be very useful.
Otherwise without a can controlled changeover I was going to have to put a tone down the aux input then detect it on the bluetooth microphone as the sound entered the cabin. (method that beats pressing a button to tell the correct audio channel is connected!)

Does anyway have a full pinout of the RAD 2 / pro radio connectors ?

I think a T-Wiring loom is my best option then I can pickup on power / K Can and the mute without breaking any wires / invalidating a warranty.
Ultimately I'll put my little can module with bluetooth in here then there will be no other wiring needed (fingers crossed).

I lifted this by the way from a product called CANM8

Locate a convenient point to connect the TALK interface CAN wires to the BMW CAN Bus. The BMW CAN Bus used is always a twisted pair of wires which are colored : ORANGE / GREEN = CAN HI & ORANGE = CAN LO on 1 & 3 series models.
On 5 & 6 Series, the wires are BLACK = CAN HI & YELLOW = CAN LO

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      02-19-2009, 05:04 AM   #52
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rad2 mute

Hi

It turns out (according to other forums / installers) that

quote

You can not route the sound through aux-in because you cannot tell the radio to automatically switch to aux when a call comes. And theres no mute in on the radio because the factory phone systems send that info via CAN-BUS. There isnt even an ignition lead on the radio (that you could cut with a relay when a call comes in), since the radio gets the info of ignition on/off via CAN-BUS as well. Next thought would be to cut the speaker wires with relays, but on 10 speakers, that would be quite a drag. So Id say: Time for a professional install (if you can find a real pro that wont chop up your E90 badly)

can anyone confirm this ?

Peter
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      02-22-2009, 11:28 AM   #53
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Quote:
Originally Posted by HighVoltage View Post
No, OBDII is on its own bus.

The SZL is on FCAN and PTCAN. The PTCAN is of note as I believe this is how the Performance wheel gets its data.
Are you sure the SZL is on PTCAN? The wiring diagram in the install doc for the perf wheel point to tapping into CAN leads off what (I think) is the JBE. So the question would be why tap in there if SZL is already on PTCAN? Unless they're jumping on another bus?
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      02-23-2009, 10:14 AM   #54
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Quote:
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Are you sure the SZL is on PTCAN?
The wiring diagram in the install doc for the perf wheel point to tapping into CAN leads off what (I think) is the JBE. So the question would be why tap in there if SZL is already on PTCAN? Unless they're jumping on another bus?
No, I think there was some confusion on my part. The SZL is on F-CAN but according to the perfomance wheel documentation Ive seen, the SZL indirectly brings up the PT-CAN (via a retrofit kit). I don't believe the SZL is directly communicating on PT-CAN although it may be doing so indirectly via the DSC for other reasons.

"F-CAN Link
The DSC control module is connected via the F-CAN to the SZL and serves as the gateway
for the SZL, allowing data from the SZL to be distributed to the other control modules."

For clarity, below is the circuit diagram and connection diagram (retrofit harness) distributed with the perf wheel. A7 connects to the coil spring which is mounted to the SZL. The coil spring interfaces to the wheel. A3 and A4 are the CANH/CANL lines to PTCAN.
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      02-23-2009, 10:56 AM   #55
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Quote:
Originally Posted by HighVoltage View Post
2. Maybe. On the E46 you could tap onto the IBUS through the CD changer, however that is now on a MOST bus, as are all the audio components. I'm not sure if there are any modules on KCAN back there. TCU maybe? Ill see if I can find something, as I would prefer that location for a permanent install.
I think Im getting close to a solution for this. The CAS2 and PDC are both located in the rear. We just need the wiring diagram for these to find the K-CAN lines. For those with either Comfort Access or PDC they may have a trunk access solution..
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      03-03-2009, 03:56 PM   #56
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Quote:
Originally Posted by gasmeter View Post
Hi

It turns out (according to other forums / installers) that

quote

You can not route the sound through aux-in because you cannot tell the radio to automatically switch to aux when a call comes. And theres no mute in on the radio because the factory phone systems send that info via CAN-BUS. There isnt even an ignition lead on the radio (that you could cut with a relay when a call comes in), since the radio gets the info of ignition on/off via CAN-BUS as well. Next thought would be to cut the speaker wires with relays, but on 10 speakers, that would be quite a drag. So Id say: Time for a professional install (if you can find a real pro that wont chop up your E90 badly)

can anyone confirm this ?

Peter
This is certainly not true! There is a message on the K-CAN that can force the CCC to select AUX-IN. It is actually a message that you can request which ITEM to select in the AUDIO menu. The message contains the ROW number and how many items from the right. Stupid but its how it works.

Obviously you would not be able to return from AUX back to CD/Radio or wherever you were. The reason is simple. There does not seem to be a way to read what source is currently selected, but again you can select any source.

The proof is how the BMW ACM CAN interface does it on the K-CAN bus. I can configure it to select any source I like, including AUX-IN.
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      03-11-2009, 09:52 AM   #57
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Quote:
Originally Posted by HighVoltage View Post
No, I think there was some confusion on my part. The SZL is on F-CAN but according to the perfomance wheel documentation Ive seen, the SZL indirectly brings up the PT-CAN (via a retrofit kit). I don't believe the SZL is directly communicating on PT-CAN although it may be doing so indirectly via the DSC for other reasons.

"F-CAN Link
The DSC control module is connected via the F-CAN to the SZL and serves as the gateway
for the SZL, allowing data from the SZL to be distributed to the other control modules."

For clarity, below is the circuit diagram and connection diagram (retrofit harness) distributed with the perf wheel. A7 connects to the coil spring which is mounted to the SZL. The coil spring interfaces to the wheel. A3 and A4 are the CANH/CANL lines to PTCAN.
Yes. SZL is on F-CAN. The packet data is foward to PT-CAN by DSC. Then JBE foward the data from PT-CAN to K-CAN.

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      03-11-2009, 09:55 AM   #58
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Originally Posted by HighVoltage View Post
I think Im getting close to a solution for this. The CAS2 and PDC are both located in the rear. We just need the wiring diagram for these to find the K-CAN lines. For those with either Comfort Access or PDC they may have a trunk access solution..
Agree! I post the PDC wiring diagram on floor 42. Who can post the Comfort Access(CA) wiring diagram in case of the car without PDC?
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      03-11-2009, 10:01 AM   #59
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Quote:
Originally Posted by glamprecht View Post
This is certainly not true! There is a message on the K-CAN that can force the CCC to select AUX-IN. It is actually a message that you can request which ITEM to select in the AUDIO menu. The message contains the ROW number and how many items from the right. Stupid but its how it works.

Obviously you would not be able to return from AUX back to CD/Radio or wherever you were. The reason is simple. There does not seem to be a way to read what source is currently selected, but again you can select any source.

The proof is how the BMW ACM CAN interface does it on the K-CAN bus. I can configure it to select any source I like, including AUX-IN.
I think these messages may not be transmited into bus.

Just imaging CCC is a computer, Controller is the mouse, LCD is the monitor. You can use mouse to select a item in monitor, but it was jut a direction signal not the command itself. All the process is CCC inside.

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      06-27-2009, 02:19 PM   #60
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I've finally managed to get the interface to start reading some messages off the K-CAN and I can see messages for the iDrive, windows etc. But I can't see a single message for any of the steering wheel buttons. I'm reading the K-CAN so has anyone been able to read the steering wheel buttons from the K-CAN?
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      07-08-2009, 06:16 PM   #61
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Hi,
searching the Net I found page one of this thread which looks very important to me.
In fact, I would like to find CAN Code to control the rear side windows from my own CAN-Module.
Until I know how it works and what to do I use my notebook instead.
Currently its connected to CAN 11bit 125 Kbaud and can scan all relevant messages.
As Im work on these just few weeks I have some questions:
1) have I to take car of this different buses
Switch -> LINBUS -> FRM -> KCAN -> JBE -> KCAN -> Window motor
If Im connected to possibly one of these I think I can send the right command to control the window motor.

I have found several messages like window position, moving or not etc.
But I need some help to understand (how to find out) what is the initial command

I.e. lets take the cabin lights from HighVoltage at the beginning of this threat.
Code:
CANID LEN DATA Notes:
1E3 ___ 2 ___ F1 FF ____ Command, wait for response
21A ___ 3 ___ 00 10 F7__ Response
1E3 ___ 2 ___ F0 FF ____ Command
2) HighVoltage, how do you found/ decided 1E3 is the command ID and not any message
3) Is there any relationship between 1E3 and 21A or how you found that?
4) Do I understand well, if I send 1E3 . . . to the bus cabin light will go on/off?
5) I have a problem to understand:
Request ID Response ID (from diff. examples)
745 _____ 74D ___ (diff. 8)
7E1 _____ 7E8 ___ (diff. 7)
7E0 _____ 7E8 ___ (diff. 8)
7EE _____ 7?? ___ as far as it is possible
1E3 _____ 21A
Its enough for today.

(Questions are just in general, Im not really talking about BMW)
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      07-09-2009, 09:27 AM   #62
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Quote:
Originally Posted by a_colonia View Post
Hi,
searching the Net I found page one of this thread which looks very important to me.
In fact, I would like to find CAN Code to control the rear side windows from my own CAN-Module.
Until I know how it works and what to do I use my notebook instead.
Currently it’s connected to CAN 11bit 125 Kbaud and can scan all relevant messages.
As I’m work on these just few weeks I have some questions:
1) have I to take car of this different buses
Switch -> LINBUS -> FRM -> KCAN -> JBE -> KCAN -> Window motor
If I’m connected to possibly one of these I think I can send the right command to control the window motor.

I have found several messages like window position, moving or not etc.
But I need some help to understand (how to find out) what is the initial command

I.e. let’s take the cabin lights from HighVoltage at the beginning of this threat.
Code:
CANID LEN DATA Notes:
1E3 ___ 2 ___ F1 FF ____ Command, wait for response
21A ___ 3 ___ 00 10 F7__ Response
1E3 ___ 2 ___ F0 FF ____ Command
2) HighVoltage, how do you found/ decided 1E3 is the command ID and not any message
3) Is there any relationship between 1E3 and 21A or how you found that?
4) Do I understand well, if I send 1E3 . . . to the bus cabin light will go on/off?
5) I have a problem to understand:
Request ID Response ID (from diff. examples)
745 _____ 74D ___ (diff. 8)
7E1 _____ 7E8 ___ (diff. 7)
7E0 _____ 7E8 ___ (diff. 8)
7EE _____ 7?? ___ as far as it is possible
1E3 _____ 21A
It’s enough for today.

(Questions are just in general, I’m not really talking about BMW)
1) No you can just focus on the KCAN bus. I mention the relationship because as we try to determine the origin of the messages its important to understand the flow of communications.

2) I explain how I determined what each CANID corresponds to in post #4. In short, I built a function in my program that captured all the "idle" traffic on the bus. Meaning I would get in the car, start my program, and let the car talk a few seconds without doing me doing anything (just sit there). I would then tell my program to filter out all of those messages it just saw. Then I would push a button in the car and my program would capture the new messages.

3) The relationship is defined in the "Notes;" The 0x1E3 CANID is essentially coming from the button when you press it/release it. The JBE (Master) responds to that message with the CANID of 0x21A. I havent yet determined what the data (00 10 F7) from the JBE means though.

4) If you send 1E3 F0 FF then the cabin lights will go off. The sequence for turning the lights on and keeping them on, is more complicated and explained in post #1.

5) I dont understand what you are asking in this question. Im sure it is just a simple language barrier/translation problem.
EDIT: Are trying to find some relationship between the CANID in a request and corresponding response? There doesnt need to be any although there typically is depending on the protocol. I havent yet determined the meaning of each bit in the CANID. In most protocols, some of those bits are reserved for message types (groupings, like polling, change-of-state, etc) and others as a unique identifier on the bus to differentiate one node from another.
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      07-09-2009, 04:36 PM   #63
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Hi guys,

finally, i found some _real_ info on this kind of stuff, thanks! It seems everyone else on the web has an I-BUS in their car...

So, my 1 series also has the K-CAN bus, and i would like to listen in on it, especially the radio/steering wheel buttons. There are two buttons (telephone, voice command) that have absolutely no effect, they must obviously be put to some use :P

Doing computer science, i have no problem with software, but could you guys recommend some hardware solutions that work reliably, if possible USB solutions? At this point, I don't care if I tap in at the PDC or behind the radio, but are there any disadvantages to either? I guess for a permanent car PC it would make sense to put it in the trunk..

Thanks,
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      07-09-2009, 05:08 PM   #64
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Quote:
Originally Posted by ploedoff View Post
Hi guys,

finally, i found some _real_ info on this kind of stuff, thanks! It seems everyone else on the web has an I-BUS in their car...

So, my 1 series also has the K-CAN bus, and i would like to listen in on it, especially the radio/steering wheel buttons. There are two buttons (telephone, voice command) that have absolutely no effect, they must obviously be put to some use :P

Doing computer science, i have no problem with software, but could you guys recommend some hardware solutions that work reliably, if possible USB solutions? At this point, I don't care if I tap in at the PDC or behind the radio, but are there any disadvantages to either? I guess for a permanent car PC it would make sense to put it in the trunk..

Thanks,
Ploedoff
Welcome.

It doesnt matter where you tap onto the bus, just pick the spot that is most convienient. Sorry, I dont have any hardware suggestions. However if I were looking for something, I would try to find something that gives me access to the low level driver.
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      07-09-2009, 05:28 PM   #65
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So is there anything else i need to take into consideration? Like, "keep the wires short or twist them", or "make sure you terminate with X ohms"?

And is any can-usb electrically compatible (voltages etc), or could choosing the wrong one result in broken units?

Cheers,
P
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      07-10-2009, 09:10 AM   #66
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So is there anything else i need to take into consideration? Like, "keep the wires short or twist them", or "make sure you terminate with X ohms"?
It is a differential bus but its unlikely you will need a twisted pair considering the length. If you have easy access to twisted pair then be all means do so, shielded would be even better. In the "final" application (e.g CarPuter, etc) I would use a shielded twisted pair to minimize the introduction of noise. You shouldnt need to terminate the bus (120 ohm) as both ends of the trunk on the vehicle should already be terminated. If you do see an issue, you can always try adding one. You wont damage the vehicle although you may throw a code.

Quote:
Originally Posted by ploedoff View Post
And is any can-usb electrically compatible (voltages etc), or could choosing the wrong one result in broken units?

Cheers,
P
Although some application protocols dictate additional physical layer requirements, CANH and CANL are not really variable in this respect. Whats far more important is the use of a common mode reference. Although you may be able to get away without using GND you may have bit rate issues (attributable to ground offset) and more importantly you may risk damage to the transceivers on the trunk if the tolerable ground offset of the transceiver(s) is exceeded.
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