CAN XML for boolean output from bitwise operations

General
1

I’m trying to write the XML to map the turn indicators. The car (2011 Corsa D) also has ‘comfort’ indicators - the three flash thingy, so there are two values for each side. Sniffing the HS-CAN activity, I can see the indicators toggling bits on 0x361 in the top nibble of the first byte. So:

0010 xxxx Left comfort indicator on
0100 xxxx Right comfort indicator on
0110 xxxx Left indicator ON
1000 xxxx Right indicator ON

How do I write the XML so that either comfort OR ON lights up the dashboard icon?

I have tried shifting the bits right and bitwise ANDing with the appropriate values:
<value targetId=“160” offset=“0” length=“1” units=“bit” conversion=“((V >> 4) & 2) || ((V >> 4) & 6)”>
<value targetId=“161” offset=“0” length=“1” units=“bit” conversion=“((V >> 4) & 4) || ((V >> 4) & 8)”>

but I don’t get expected behaviour. I’m guessing my syntax may be wrong.

As a side note, if anyone has a reliable source for (UK) 2011 Corsa D CAN IDs for basic stuff and/or the CAN XML for them, that would be great. I’m not bothered about the technical stuff like IAT/ AFR etc, more just like general instrument panel indicators and readings. Co-pilot just makes stuff up and there is a lot of conflicting info on the web!

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Update: Changing tack, I’ve tried the enum operator, so:

<value targetId=160 offset=0 length=1 startbit=5 bitcount=3 enum=1:1,3:1,#:0 >
<value targetId=161 offset=0 length=1 startbit=5 bitcount=3 enum=2:1,4:1,#:0 >

The left indicator now works for both comfort and ON, but the right indicator is not working at all.

Any ideas? I’m tearing my hair out on what should be a really simple bit of code!

3

Update 2 :

Now sorted - It was because enum doesn’t return a single bit when specifying a 0 or 1, I assume it returns a byte which isn’t being recognised by the turn indicator which is expecting a boolean (0 or 1).
I don’t know if it’s possible to force enum to return a single bit, rather than a byte (or longer)

The left hand indicator worked because the bottom bit of the byte was being set

4

How about:

<value targetId="160" offset="0" length="1" conversion="V>>4" enum="2:1,6:1,#:0">
<value targetId="161" offset="0" length="1" conversion="V>>4" enum="4:1,8:1,#:0">

Idea here is that we move those 4 bits down and just read the value and use enum to determine if value should be on/off.

5

That’s how I did it in the end. However, the value returned to realdash resulted in the input value to the indicator being between 0 and 7 (3 bits), so it srill didn’t work. I had to change the input value to 0 and 1, then it all worked

Cheers :slightly_smiling_face:

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