Has anyone ever used Flexray?

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Hello again fellow AVR users. Flexray is a 10 megabitpersec automotive bus. Its in the BMW X5 VerticalDynamicsModule. I see several chip makers have flexray tranceivers and flexray controllers. Looks like most of them have 16 data bits, which makes the flexray controllers more compatible with an arm, but it might be possible to use an avr. I've been reading the datasheets for flexray eval boards and flexray readers/scanners like IntrepidControlSystems. Seems like can bus maxes out at 500kbps and this flexray thing might be the next big thing. I'd like to be able to sniff the data thats going to and from the satelite suspension dampers in the the E70 here in the garage, and if you know how to read and write flexray, I'd sure like to get a pm from you. 

 

Imagecraft compiler user

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I do stuff involving Flexray every day. We make ECUs that link into the system busses of cars like BMW, Mercedes, Audi etc. Flexray is basically a high speed replacement for CAN because there's now so much data being passed around in a modern car a higher bandwidth was needed. As such you need a fast processor to handle the processing of the data that is passed. We use things like dual or quad core ARMs running at about 1GHz. I'm going to suggest that no, using a 20MHz AVR is NOT going to cut it I'm afraid.

 

(actually modern "automotive processors" with ARM cores likely have Flexray peripherals built in so a lot of the data processing can happen asynchronously to the main CPU anyway. Also a lot of these automotive processors actually have 4/5/6 ARMs on the silicon. There could well be dual core Cortex A8 or A15 and then maybe a couple of Cortex M4 to mop up some of the more "mechanical work". I'd imagine it might well be one of the M4s that spends most of its life handling this kind of comms).

 

A very quick google for "ARM flexray peripheral" turns up devices such as this:

 

http://www.ti.com/product/TMS570...

 

(TI are one of the main players in automotive processors)

 

EDIT: Sorry missed the "not for new design" there. In which case perhaps something along these lines:

 

http://www.ti.com/product/tms570...

Last Edited: Tue. Feb 9, 2016 - 09:16 AM