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From: dan@rna.UUCP (Dan Ts'o)
Newsgroups: net.music.synth
Subject: Midi specs, please...
Message-ID: <450@rna.UUCP>
Date: Sun, 17-Nov-85 17:01:12 EST
Article-I.D.: rna.450
Posted: Sun Nov 17 17:01:12 1985
Date-Received: Sat, 23-Nov-85 03:28:02 EST
Reply-To: dan@rna.UUCP (Dan Ts'o)
Organization: Rockefeller Neurobiology
Lines: 29

x
	Where can I find out the hardware and sofware definitions of MIDI ?
What are the electrical characteristics of MIDI, the protocols/command and
data formats used ?

	I have seen various articles stating the baud rate of MIDI to be
either 31500 or 31250 - which is it ? 31250 is easier to generate. I also
understand that it is current loop, is it identical to the old 20ma current
loop ? I also hear that MIDI requires opto-isolation.

	Would it be reasonable to convert an old DEC serial interface, DL-11 or
DLV-11, to MIDI ? They both have external clock inputs and can both be set for
20ma current loop. What would be required ?

	How do these PC's hack a 31.25Khz interrupt rate (maybe they do polled
I/O) ? Would writing a patch librarian from scratch be completely ridiculous
(it doesn't seem too hard...)

	Thanks.

					Cheers,
					Dan Ts'o
					Dept. Neurobiology
					Rockefeller Univ.
					1230 York Ave.
					NY, NY 10021
					212-570-7671
					...cmcl2!rna!dan
					rna!dan@cmcl2.arpa