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From: David Woodhouse <dwmw2@infradead.org>
To: Russell King <rmk@arm.linux.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>,
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Date: 16 Mar 2003 10:51:47 +0000
Subject: Re: RS485 communication
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On Sun, 2003-03-16 at 10:35, Russell King wrote
> No - that's not how RS485 works.  With a balanced line, the result
> that any one receiver will see will depend on it's position on the
> line and the relative distance to each transmitter, the resistance
> of the line, and the manufacturer/type of the RS485 transceiver.
> In other words, the state you see is indeterminent.

Ah, OK. Then I must have been mistaken in thinking that CAN was based on
RS485 -- or mistaken in remembering that that's how CAN does collision
avoidance I suppose, but I suspect the former is more likely.

Thanks for the correction.

-- 
dwmw2


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