OBC display databus for Valentine One

[ztan]

Hi,
Does anyone have the specifics of the databus or display that BMW uses for the 7, 11, and 18 button OBC units?
I found the specifics for the Valentine One remote display stream here: http://www.mp3car.com/vbulletin/attachment.php?attachmentid=6457
and am wondering if it is possible to wire a V1 to display through the OBC display. That would make the "OBC" a seriously worthy addition to my car.
Regards,
Ezekiel

[x2nervisx]

They do it for the e46's but that would be awesome if someone found a way to do it to the e36's obc. If it worked I would go out and buy a valentine 1 right away. Good luck with your search.

[johnf]

Does anyone have the specifics of the databus or display that BMW uses for the 7, 11, and 18 button OBC units?First off, there is exactly one OBC and it has 18 buttons, no more and no less. The others you list are outside temperature / check control displays.

Perhaps the OBC has some undocumented pins and functions that will let you write the display. I kind of doubt it, however, given when it was designed. That was back in the days when the engineers at BMW generally sent signals over discrete wires to independant modules rather than over buses to networked controllers.

[Daved]

First off, there is exactly one OBC and it has 18 buttons, no more and no less. The others you list are outside temperature / check control displays.

Perhaps the OBC has some undocumented pins and functions that will let you write the display. I kind of doubt it, however, given when it was designed. That was back in the days when the engineers at BMW generally sent signals over discrete wires to independant modules rather than over buses to networked controllers.
I have to agree but that doesn't mean that you can't build a new OBC for the E36s that do their regular job plus showing up custom texts, right? ;)

[bmwe30is]

Hi,
Does anyone have the specifics of the databus or display that BMW uses for the 7, 11, and 18 button OBC units?
I found the specifics for the Valentine One remote display stream here: http://www.mp3car.com/vbulletin/attachment.php?attachmentid=6457
and am wondering if it is possible to wire a V1 to display through the OBC display. That would make the "OBC" a seriously worthy addition to my car.
Regards,
Ezekiel

Ezekiel, here's some info about BMW's I-Bus:

http://www.openbmw.org/bus/

http://autos.groups.yahoo.com/group/HackTheIBus/

I don't remember which car the information relates to, but this should help you get started in the right direction.

- Jonathan

[johnf]

Unfortunately, that stuff appeared in the next generation 3er.


I have to agree but that doesn't mean that you can't build a new OBC for the E36s that do their regular job plus showing up custom texts, right? ;)Indeed, and in some ways, the job is easier than on later cars as you can electrically measure and manipulate the individual signals. Arguably, you just have to be willing to add enough i/o lines, electronics and wires.

[dmurray14]

Ezekiel, here's some info about BMW's I-Bus:

http://www.openbmw.org/bus/

http://autos.groups.yahoo.com/group/HackTheIBus/

I don't remember which car the information relates to, but this should help you get started in the right direction.

- Jonathan

Yes, but that's only on 96+, and has been covered. Don't think anyone's covered the older databus protocols, though I'd love to get my hands on that info. From what I understand, there is a 2 wire bus that goes from the OBC to DME, other than that I'm not too sure.

Dan

[bmwe30is]

Yes, but that's only on 96+, and has been covered. Don't think anyone's covered the older databus protocols, though I'd love to get my hands on that info. From what I understand, there is a 2 wire bus that goes from the OBC to DME, other than that I'm not too sure.

Dan

I might be able to get some of my EE professors to help me decipher that stuff.

Lemme poke around when I get some free time later this week and I'll let you guys know.

- Jonathan

[Spood]

I have nothing to contribute other than how wicked that would be to make work... In for subscription. :)

[dmurray14]

I might be able to get some of my EE professors to help me decipher that stuff.

Lemme poke around when I get some free time later this week and I'll let you guys know.

- Jonathan
Cool. I may be able to whip something together if you found some info. However, I wouldn't be too surprised if there wasn't the ability to send messages to the screen...I'm guessing the CCM (check control module) just sends which error has been triggered, not the text to display. But I may be wrong...

[ztan]

If the databus is not easily accessible for miscellaneous information display, how about a standalone display module in BMW amber to fit in somewhere else in the dash, or hijacking the odometer display?

Alternatively, has anyone hard-wired an accelerometer into an E36 and given it a "stock" look?

Regards,
Ezekiel

[RaDaRkInG]

See if this will help you:



http://www.radardetector.net/viewtop...ght=navigation

http://www.exitzer0.com/

The V1 Virtual display is a project to allow the capture and display of the alert data from the Valentine One® Radar Locator from Valentine Research Inc. The software runs on a computer attached to the Valentine One Remote Display port. It is designed first and foremost for use in a CarPC.

http://www.kc8unj.com/radar/

Software Features:
Connect to the Valentine One radar detector via serial or USB port
Emulate the remote display unit
Log radar alert data to a PC file

Software One might be useful for:
Users of in-vehicle PC's
Evaluating detector performance
Evaluating the effect of different settings in the Valentine One programming
Evaluating radar sources over a driving route

[dmurray14]

See if this will help you:



http://www.radardetector.net/viewtop...ght=navigation

http://www.exitzer0.com/

The V1 Virtual display is a project to allow the capture and display of the alert data from the Valentine One® Radar Locator from Valentine Research Inc. The software runs on a computer attached to the Valentine One Remote Display port. It is designed first and foremost for use in a CarPC.

http://www.kc8unj.com/radar/

Software Features:
Connect to the Valentine One radar detector via serial or USB port
Emulate the remote display unit
Log radar alert data to a PC file

Software One might be useful for:
Users of in-vehicle PC's
Evaluating detector performance
Evaluating the effect of different settings in the Valentine One programming
Evaluating radar sources over a driving route


Yeah, that's cool and all, the problem is we don't have the information for the BMW side of things. The V1 info has been out there...

Dan

[Phat Ham]

This is something I've been thinking about looking into for a while. But I'm lazy. Didn't some e36s use ibus like the newer bmws do? Even if you can't get the databus protocol going to the obc you could probably hack the obc display itself. i.e. hijack the display (or whatever is controlling the display) and send it your own messages. How much does an obc go for these days? If they aren't too expensive I might buy one just to mess around with.

[bmwe30is]

This is something I've been thinking about looking into for a while. But I'm lazy. Didn't some e36s use ibus like the newer bmws do? Even if you can't get the databus protocol going to the obc you could probably hack the obc display itself. i.e. hijack the display (or whatever is controlling the display) and send it your own messages. How much does an obc go for these days? If they aren't too expensive I might buy one just to mess around with.


I believe the E36 has a more "primitive" version of the i-bus.

I have no idea how much a used OBC goes for, I'm tempted to take mine out and find out what it holds.

I need to grab one of my school's oscilliscopes and see wtf is goin on with signals goin to the OBC...

[dmurray14]

This is something I've been thinking about looking into for a while. But I'm lazy. Didn't some e36s use ibus like the newer bmws do? Even if you can't get the databus protocol going to the obc you could probably hack the obc display itself. i.e. hijack the display (or whatever is controlling the display) and send it your own messages. How much does an obc go for these days? If they aren't too expensive I might buy one just to mess around with.

96+ has iBus

[tmat256]

According to the websites that were first posted, the 96+ only used ibus for the connection between the headunit and cd changer. This means that any OBC type of stuff would not use ibus for any e36.

I'm slightly confused about

First off, there is exactly one OBC and it has 18 buttons, no more and no less. The others you list are outside temperature / check control displays.


I thought that outside temp and check control WERE the OBC??? I mean I know other ones do nice stuff with showing speed and mpg but I thought it was still an OBC.... granted either way it doesn't matter because they both apparently don't use ibus.

[johnf]

I thought that outside temp and check control WERE the OBC??? I mean I know other ones do nice stuff with showing speed and mpg but I thought it was still an OBC.... granted either way it doesn't matter because they both apparently don't use ibus.All these things are officially "Multi Information Displays" (MIDs). BMW calls the 18-button unit that can compute the car's average speed, fuel consumption, time to destination and so on, the OBC (On Board Computer / Bordcomputer) because it can compute these things. The others can't really compute anything so BMW doesn't call them OBCs, or think of them that way.

Anyway, the only bus the E36 OBC is on is the diagnostic bus. That bus is normally silent while the car is moving. In fact, if I make no mistake, the engine compartment diagnostic connector cap shorts it to ground to insure it is silent. Probably, the most promising way to get text into the OBC would be over the check control data and clock lines. Someone should sniff the traffic going over them. I doubt it has a high data rate and it might have some way for the check control module to pass strings to the OBC it should display.

[dmurray14]

All these things are officially "Multi Information Displays" (MIDs). BMW calls the 18-button unit that can compute the car's average speed, fuel consumption, time to destination and so on, the OBC (On Board Computer / Bordcomputer) because it can compute these things. The others can't really compute anything so BMW doesn't call them OBCs, or think of them that way.

Anyway, the only bus the E36 OBC is on is the diagnostic bus. That bus is normally silent while the car is moving. In fact, if I make no mistake, the engine compartment diagnostic connector cap shorts it to ground to insure it is silent. Probably, the most promising way to get text into the OBC would be over the check control data and clock lines. Someone should sniff the traffic going over them. I doubt it has a high data rate and it might have some way for the check control module to pass strings to the OBC it should display.

Do you know anything about the diagnostic protocol? I hooked my laptop up to the TxD RxD and grounds, but didn't see anything. Any idea how to wake it up? I'm assuming it needs a bit set before the ECU responds with anything. There is also the possibility that it's TTL, too. Not sure though...

Thanks,
Dan

[johnf]

It is a 9600 baud, 12V open collector bus so you would need something like a MAX232 and a transistor to convert it to RS-232.

[tmat256]

We should come up with a list of things that throw a Check Control. This way he has things to test for.

I know of a few but I'm sure you guys have some more:

- Coolant Low
- Brake Light Curcuit
- Washer Low

I'm sure if you look through the wiring in a Bentley you'll see everything hooked up to it.