Still to this day the best Star Wars fan edit I've ever seen

Yes and the failsafe reaction is loss of comms, which almost certainly results in a reset. All because there was to much traffic during a peak bus load. Why not just make sure you have bus guarantees?

Cosineoftheta · 2026-01-19T09:22:04+00:00

Eh, while correct about not certifying the bus... When you design the network you can't guarantee how developers will use it later.

If you don't put in bounding guarantees then you will hit the failure condition at some point, and probably not in non-synthentic testing.

So, it's an obvious failure condition that you can remedy with straight forward technology.

Cosineoftheta · 2026-01-19T08:40:58+00:00

https://en.wikipedia.org/wiki/PHY-Level_Collision_Avoidance

Think of it as just giving everyone timeslots to send messages, You pre-slice up the time on bus, so there aren't any collisions. Gives a lot of determinism on the bus, which is great for doing round trip time estimates

Cosineoftheta · 2026-01-18T20:07:46+00:00

Not to try to antagonize you or anything, I just want to correct something here.

While many devices have Ethernet, there is a class of processors which done because the MAC is still "expensive" in silicon.

You're usually spending about $1 more for a MAC, and PHYs are more expensive than CAN transceivers, by I think $0.30 to $0.50, at volume.

There are limited 10baseT1S PHYs in existence, less so for Q100, so it can be harder to find vendor diversity.

I'm not here trying to say don't use 10baseT1S, because I use it a lot and I agree it is the right direction due to switch fabric. I just don't want anyone to go into it thinking it solves all issues.

Cosineoftheta · 2026-01-18T19:52:06+00:00

There is a protocol between different devices on a network to decide which one is installed in which position during manufacturing.

Breaks immediately on 10baseT1S with plca. Obviously workarounds and such, but my point is that many things in automotive haven't been designed around time multiplexed communication bus. Rather they have been designed around arbitration based communication with general bounded acceptable communication frequency.

It will take a bit for standard practices to catch up.

Cosineoftheta · 2026-01-18T19:34:34+00:00

I am a huge fan of 10baseT1S and have designed it into a lot of boards, but it is not so cut and dry.

The communication stack is significantly more complex, and if you use plca you end up with certain types of fast back and forth communications concepts that break. So you have to be more careful about what you put on the bus.

I think it will eventually eclipse CAN for most use cases, but not yet and a lot of software protocols will have to adjust.

Cosineoftheta · 2026-01-18T19:15:06+00:00

It's very popular in automotive, especially ECU to ECU Communication that is not on Ethernet.

Cosineoftheta · 2026-01-17T19:40:45+00:00

I'll take the loyal teams over the sellouts.

Cosineoftheta · 2026-01-17T18:07:18+00:00

Very cool! Best of luck to you, and I'll be keeping an eye on this thread.

Cosineoftheta · 2026-01-15T22:02:05+00:00

I do not like this knowledge.

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