In
<77142d37c0c3c34da0d7b1da7d7ca3433336c...@nwt-s-mbx1.rocketsoftware.com>,
on 02/16/2012
at 08:55 PM, Bill Fairchild <[email protected]> said:
>Seymour is right that we have had subchannel numbers since 1983
>instead of device addresses, but we have also had device numbers
>since 1983.
At the same time, and not necessarily with the same values.
>As John Gilmore explained in an earlier post, we used to have 12-bit
>device addresses composed of three parts, the channel number,
>control unit number within the channel, and device number within the
>control unit within the channel.
It wasn't quite that clean; the uu part of the cuu split differently
depending on the control unit. The 8 bits of uu were presented on the
channel and it was up to the control units to recognize which belonged
to it and which didn't. Some control units had fewer than 16 devices,
some had more.
--
Shmuel (Seymour J.) Metz, SysProg and JOAT
ISO position; see <http://patriot.net/~shmuel/resume/brief.html>
We don't care. We don't have to care, we're Congress.
(S877: The Shut up and Eat Your spam act of 2003)
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