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From: Don Y <blockedofcourse@foo.invalid>
Newsgroups: sci.electronics.design
Subject: Re: Re:Positional/physical addressing
Date: Tue, 24 Jun 2025 09:49:26 -0700
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On 6/24/2025 9:18 AM, Martin Rid wrote:
> CAN network?

Each CAN node either needs a unique address to which messages can be
directed;  *or*, to KNOW to listen for particular BROADCAST messages.

So, you either send a message to node 5 to do something
OR, you send a message about that something and expect
that node to know that *it* should process that message.

If all of the nodes are *identical* (hardware and software),
there is nothing to distinguish one device from any other.

If you require an "address"/ID to be programmed into the device
to "make it distinguishable from its neighbors", then you've
added a labor step and a configuration management activity
(how do you know that you don't have two 5's?  how do you know
that the device in your left hand is 5 and your right hand is 23?)

Ideally, you just want the user to reach into a bag of identical
parts and plug them in without concern for which goes where -- and
have the system sort all of that out FOR the user.