MSD80/81 CANbus Boost

samuria

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Nov 30, 2021
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Has anyone successfully decoded boost pressure from OBD canbus?

I have not tried tapping into PT-CAN yet, just waiting for an Arduino shield to arrive before splicing a canbus wire. But getting boost from OBD should be possible as these dongle are able to do it somehow - albeit may be a little slower.

I have already checked out the loopybunny website, as well as a few canbus projects related to the E9X platform.

Thanks
 
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AzNdevil

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good question, i havent found anything when i first looked at it, this would be helpful feeding into racechrono
actually i am working on something like this recently
 

carabuser

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It's not broadcast from the DME. If you wanted to read boost then you would have to set up a request over KWP to the DME (you can access it by requesting the common identifier). That is how COBB/MHD handles it for their logging, but rather than common identifier they specify the exact RAM address because they are bulk reading many parameters at once.
 
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AzNdevil

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It's not broadcast from the DME. If you wanted to read boost then you would have to set up a request over KWP to the DME (you can access it by requesting the common identifier). That is how COBB/MHD handles it for their logging, but rather than common identifier they specify the exact RAM address because they are bulk reading many parameters at once.

thats what i was afriad of... i want to keep it simple and stupid

thanks anyways though, saves me a lot of time trying to figure it out
 

AzNdevil

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If there is a large enough demand for it, we could add an additional 100ms broadcast of 4/6/8 parameters (depending on resolution needed) for dash displays, configurable from a preset list of possible ram vars.

thanks for your reply!
however.... i doubt that many people care since this is only useful for data loggers and as these cars cant survive a 30 min track session without extensive cooling mods, not many people track them in the first place :(

besides, most that care about track driving/performance have moved on to other newer platforms... less hassle and certainly less work
 

samuria

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Nov 30, 2021
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It's not broadcast from the DME. If you wanted to read boost then you would have to set up a request over KWP to the DME (you can access it by requesting the common identifier). That is how COBB/MHD handles it for their logging, but rather than common identifier they specify the exact RAM address because they are bulk reading many parameters at once.
Do you know if we can make KWP requests to the DME via KCAN? Or does it have to go through DCAN?
 

hollracing

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Oct 26, 2022
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I currently use an Arduino Mega2560 to log e8/9x PTCAN to my laptop in .csv if anyone wants I can help or share my sketch.
I use wintax4 to analyze so not sure what you would use but just needs to be able to load .csv
Logger.jpgLogger2.jpgLogger3.jpg
 

samuria

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Nov 30, 2021
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I currently use an Arduino Mega2560 to log e8/9x PTCAN to my laptop in .csv if anyone wants I can help or share my sketch.
I use wintax4 to analyze so not sure what you would use but just needs to be able to load .csv
View attachment 93708View attachment 93709View attachment 93710
I have a python project to interact with the KOMBI through KCAN. I use an Arduino with an MCP2515 chip. Do you log anything that isn't broadcast, like boost? I'd be interested in taking a look at your code.
 

hollracing

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I have a python project to interact with the KOMBI through KCAN. I use an Arduino with an MCP2515 chip. Do you log anything that isn't broadcast, like boost? I'd be interested in taking a look at your code.
I'm not logging anything that isn't normally broadcast. I've sent you my sketch.
 

carabuser

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Out of interest, why would you not use a tool like MHD to log the RAM? Is it just that the refresh rate is too low?
 

hollracing

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Oct 26, 2022
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Out of interest, why would you not use a tool like MHD to log the RAM? Is it just that the refresh rate is too low?
I am interested in ABS/DSC and driving analysis, so not much info of use to me in the ECU other than RPM, Accel pedal position and the torque messages.