Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!BRL.MIL!phil
From: phil@BRL.MIL (Phil Dykstra)
Newsgroups: comp.protocols.tcp-ip
Subject: Re:  TCP/IP on MIDI?
Message-ID: <8905071842.aa01862@SPARK.BRL.MIL>
Date: 7 May 89 22:42:44 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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The aid in experimentation of TCP/IP over MIDI, I point out that it
is trivial to turn a Sun 3/50 into a MIDI controller.  It turns out
that the serial port controller can be set "close enough" to the
MIDI speed.  ADB your kernel and look at:

	zs_speed+1e?d

This is the EXTB speed.  By default the divisor will be 3 (for 38400).
If you change it to 2, you will get 30720 which is only 1.7% shy of
the desired 31250.  Poke it or change you sources if you've got them
(devsun/zs_async.c).

Then with half a dozen parts, and some simple software you can be
reading/writing MIDI (we did exactly this here).  The biggest weakness
of a Sun as a MIDI controller is the default HZ resolution of 50 Hz.
It is noticeably rough to the ear.

I guess one would have to send IP packets in MIDI System Exclusive
messages.  Anyone thought about ARP yet to map IP addrs to MIDI ports? :-)

- Phil
phil@brl.mil
uunet!brl!phil

ps: My apologies for keeping this discussion going.