Can protocol sample

[dmacnz]

Is there anyway of getting a sample of the can stream output when set to motec adl dash?

I am currently the other side of the world from my ecu and trying to build a can based project. 

Any more details available other than what’s in the help file?!

i am building a can simulator and would like it to output the same as what I can expect from my g4+ when set to motec or generic dash. 

 

Thanks

Dan

[Adamw]

To do this you would need some sort of hardware CAN interface, most of them have a software package that allows you to set up a broadcast stream.

[dmacnz]

Thanks for the reply.
The hardware simulator is being built. But I want to make sure I am going to replicate exactly what my dash will receive from my G4+. Only way I can test and debug my project being 9000km away from my race cars!!

Looking at the help file for the Generic dash for .data 2-3 is 0x000-- 0xfff for 0-15000rpm?? , I cant quite make heads or tails of the help file. Any more info on the CAN protocol specifically when using generic dash as aout would be great.
Thanks

[Adamw]

Engine speed is an easy one, it is sent as a 16bit number with a resolution of 1 and a smallest value of 0.  So:

0x0000 would be 0RPM

0xffff would be 65535RPM

Some other parameters get a little more tricky to allow finer resolution or negative values, there is a handy tool called the test calculator on the CAN setup utility that allows you to look up resolution and offset for any parameter.

 

 

[dmacnz]

Thanks for the reply. 

Very helpful. 

I will go fwoars with 11bit 500k with a can id of 1000 for the simulator using the help files “generic dash” data and hope for the best. 

Thanks

dan

[dmacnz]

Sorry One more question on the CAN output for Generic dash. 
The help file says raw. But can i assume for say the oil temp in frame 9. It is calculated (data 3*256 )- data 2). Is purely transmitted in the data 2, with data 3 being "00". (Disregaring the 50 degree offset).

Thanks

[CamB]

From my messing around with it, all the raw data in the Generic stream is the second parameter + 256 * the first parameter (in the pair). Interestingly when you set a custom stream the order is reversed... 

Is there a reason not to just use the standard convention? (I guess efficient coding?)

[Davidv]

@CamB you can set the byte order to MS first or LS first to swap the order when setting up incoming frames 

(In G4+ at least)

[CamB]

@Davidv - thanks, I should have looked more closely at that! It was easy enough to change the code (I ended up using a custom stream rather than the generic one as I had trouble capturing all the incoming CAN messages if there were too many).