RomRaider

There is someone in the BMW community that had created a datalogger using BMW's own protocol called EDIABAS. He is trying to get it to poll faster. The way it's setup right now is each request for a parameter is a separate 'job'. So you ask for a value, then the ECU sends it. Then you ask for another value, and the ECU sends that. This really slows the logging rate down. I'd like to help him get faster logging rates so I wanted to see how RR does it. If I understand correctly, RR basically sends a command to the ECU saying 'send me the following variables as fast as you can and I'll just listen'. Is that correct?

The ECU he's working with can be interfaced by using KWP2000. I believe that means it is ISO 14230? The BMW protocol seems to be as slow as molasses updating only 1 parameter 5 times per second. I wonder if there's a way to use the ISO 14230 API instead and get data rates up to 10.4K baud?

If anyone can help provide any technical details, I can refer him to this thread. Thanks for your help!

RomRaider Logger, ecuExplorer use SSM2 ReadByte command.

PacketStart(0x80) Destination(0x10) Source (0xF0) length (data bytes) ReadByteCommand(0xA8) ReadExtention (0x00 single responce\0x01 repeatable responce) (3 byte address list MSB first) checksum

ECU checks data sent and stops repeatable renewed data stream in the case the scanner tries sending anything to k-line.

ISO 14230 just uses the same physical layer, I do not think ISO 14230 API wrapper is useful for the task mentioned.

Hope this helps.

That's correct. Fast poll or 'continuous push' mode effectively doubles the bandwidth for X baudrate. tx-rx-rx-rx-rx-rx instead of tx-rx-tx-rx-tx-rx

It sounds like you need to figure out how to set the baudrate in the ecu. Subaru has a SSM routine that you can write the baudrate to, then update the baudrate in the logger to match. If the bmw ecu is capable of a higher baudrate, it may have something similar.

Thanks.

If ISO 14230 isn't good to datalog with, what do you recommend? I've attached the Swedish version of ISO 14230 implementation standard and it looks like the command syntax is similar. Is there anything in there to allow tx rx rx rx rx instead of tx rx tx rx tx rx?

I believe this is valuable?
http://markgardnergibson.com/BMW/protocol.html

Whoops, this thread is getting off-topic. I'll stop.

Well the Subaru ECU uses some KWP commands and it's own SSM protocol over the same K-Line. It seems that the BMW ECU is similar in that respect.

Do you have a Openport 2.0 cable?

I don't but I plan on getting one. How can I help if I had one? I saw your thread where you were wanted to add support for other protocols into RomRaider. If I can help with that, let me know.

That page on BMW protocol needs more detail about exactly what commands the ECU supports... presumably there is more to be learned, but it will probably require further study of the ROM code, or a lucky discovery/distribution of a BMW internal document.

Subaru's protocol, SSM, has a request for reading a set of addresses once, and a slightly different request (in the header you change a 0 to a 1, or vice versa) to read a set of addresses repeatedly with no further commands. I suspect that BMW's ECU supports something like that, just because it's so much more useful than the tx/rx,tx/rx,tx/rx way of doing things, but it's a question that can only be answered by someone deeply familiar with the BMW ECU software.

Yeah, I agree.