BMW RPM conversion

Connectivity RealDash CAN
1

Hello
I am having trouble converting RPMs from two bytes to a single value in the xml file.
ARBID: 0x316 (DME1)
-B0
-B1
-B2 RPM LSB
-B3 RPM MSB [RPM=(hex2dec(“byte3”&“byte2”))/6.4]
-B4
-B5
-B6
-B7
This is the frame I am using.

And this is what I have in the xml. I have tried some different conversions but can't seem to wrap my head around this. Hope some can point me in the right direction :slight_smile:
1 Like
2

Your XML conversion seems correct for me, but I’m not familiar with (“byte3”&“byte2”) notation.

One thing to check is the endianness of the data. Frames are little endian by default. Try to define the frame with attribute:

<frame id="0x316" endianess="big">

What BMW is this for? I’d be grateful if you can share the XML when you get it working so we can add it for all RealDash users.

3

Thanks for the reply.
I will give this a try. I have a m57 engine from a bmw e46 swapped into my Pajero. And realdash is great to get all the engine and transmission data to show, that I am unable to display on the original Pajero cluster. I did make a arduino based rpm module to drive the pajero tachometer but I would like to have it on realdash as well.
I am also collecting data from Turbolamik tcu that I have controlling my zf8hp transmission.
I will be happy to share my xml, once I have everything working like I want it to :slight_smile:

4

Hi, I have a B47 engine in my BMW 320d F30 LCI (June 2016 model). Currently, I am connecting RD using an iGate BT adaptor via OBD2 port to an Android tablet. Would be great if your xml can help read exact fuel parameters, turn signals, etc. My RPM, speed, odometer readings are all fine.

5

hi, did you get this working? i have m57n + 8hp turbolamik TCU. I would be interested in the xml file. What adapter did you use?