Slicekit and CANBUS

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Marek
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Slicekit and CANBUS

Post by Marek »

Hi,

 

i have bought the ISBUS slicecard, I'd like to ask whether it's possible to use it in order to read out CAN or J1850 PWM via a ODBII->DB9 adapter. The code and example seems to be a CANBUS implementation. My question is whether it's possible to use the same setup in order to "revert" the configuration - e.g. a car OBD-2 port -> OBD-2toDB9 cable -> ISBUS-slicecard -> slicekit -> computer setup. Basically what I want to accomplish is a OBD-II adapter.

 

thanks,

 

Marek



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infiniteimprobability
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Post by infiniteimprobability »

OBD-II brings out K-line and CAN and J1850..  The IS bus slice only has a CAN transceiver so you'd need some extra physical layer circuitry (some open drain transistors and potential divider would do it) to read K-line and J1850.

Also, we currently don't have J1850 IP - however it looks very simple indeed, and the sort of thing that the xcore could very easily decode. This would actually be an ideal beginners project..

http://www.autoelectric.by/ftp/j1850_wp.pdf

K-line is basically UART, which we do have as xSOFTIP

CAN is also available as xSOFTIP

The next thing is host comms - if you are running the tools and experimenting then you could just print to the console (easy) to get going. Or if you want something that can work standalone, then USB CDC class would be a good bet - you could just have a terminal type program at the other end. This may help for that https://www.xmos.com/zh/support/appnotes/an00124. You could even use ethernet (eg. web server) wired or wireless.. 

All very doable with XMOS and a lot of IP available to help get you started.

Marek
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Post by Marek »

Hi,

thanks for your long answer. The way I understand it the transciever is needed in order to implement CAN on Startkit as part of ECU or engine control unit that would talk to an OBD-2 adapter. Is such tranciever(full duplex or half duplex) needed in order to implement a Startkit (+is-bus slicecard?) based OBD-2 adapter that would connect to a ECU? Or is a IS-BUS slicecard needed or would GPIO slicecard be sufficient?

 

 

 

 

srinie
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Post by srinie »

Hi,

How is your work progressing on this?

Hardware docs and gerber is available @

https://www.xmos.com/support/xkits?subc ... t=16297&se...

 

 

Marek
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Joined: Sun Jan 25, 2015 4:00 pm

Post by Marek »

no work has been done since then i suspect the chip on the slice isnt full duplex so that kind of OBD implementation sadly isnt possible but i might be wrong.
Does anyone else has any more info? Perhaps a slice with full duplex chip would be awesome.
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