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Is the CAN hardware the big problem?
I think there a number of CAN hardware modules already available. And yes some are 5volt so need a second sub board to sit on a 12volt system. But if someone is looking to add their own CAN module onto a CAN network then adding a power board is the really easy part. I have been working in system integration for years and CAN database stuff is pretty hardcore. The hardware is the easy part.
Why do you need a bespoke CAN module?
 

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Discussion Starter · #3 ·
Oh, I don't know. Maybe to replace a Volvo/TRW power steering pump controller because nobody like you has a clue of the protocol, despite your massive database?

So, that hardware needs to be prototyped somehow. You know..."the easy part" 😂 (which is why you do software, cuz hardware is just too easy). Nothing worse than debugging stuff you shouldn't have to, which is one reason Arduino and Pi make sense.

If you're reckless or experienced, you don't necessarily need to breadboard, as here, or you can use a breadboard shield, sure.

This is out there...it may be useful to someone, which is why I posted it. I'm not going to defend its existence.

Whether I need it or not...not now, but it's there if I ever need it which is the point here - awareness vs reinventing the wheel cuz there are bigger fish to fry an development risks better placed elsewhere.

But yes, as the sniffer you've closed-mindedly taken this to be, you taking a pass on it is the right move.
 

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Sorry we appear to have got off on the wrong foot here.
I completely agree the all information is good information and making this aware to the community is a worthy task.
I was actually looking into making my own CAN module and this certainly seems a sensible piece of HW.

I guess the point I was trying to make was that to build a simple 2 module CAN bus using a OEM module, such as a power steering pump, and a CAN module such as the Arduino is a really neat solution. A second hand pump, an off the shelf cheap CAN module and a couple of wires and termination resistors and you are good to go.

But the problem, as I see it, is not the hard wear but the CAN massages.
How do you find the technical information on the CAN massage the pump is expecting to receive?
Unless this CAN massage data is readily available, then for me, cracking the CAN massage set required to gain the functionality required from the pump is really really hard to do.

I guess all I was trying to do was highlight that CAN massages are hard. And there probably isn't much point buying hard wear until you have fully understood and crack CAN massages.

As Jeremy Clarkson would say " CAN massages, how hard can it be. Turns out to be very hard"
 

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Discussion Starter · #6 ·
If you have a working car to stare at, it's elbow grease and sleuthing. For some people, it's like solving puzzles as an enjoyable way to pass time.

You do what you gotta do. Fortunately, there are nonselfish people in the community who put their knowledge and findings out there. We'd be nowhere without VCU's, and without manufacturers who publish their CAN protocols.

It's the ones that put up stone age walls around information like CAN protocols for modules that need to get it in gear.

Nobody's going to build a Mach-E car clone to compete with Ford, yet if I want to use Ford's traction inverter with their "Eluminator" crate motor, their program manager returns an email, telling me "no, I can't give that out, proprietary information". A gas pedal position, or RPM, message, is somehow proprietary? 😂
 
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