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From: albaugh@dms.UUCP (Mike Albaugh)
Newsgroups: comp.sys.dec
Subject: Re: Max baud rate on DS3100 serial line.
Message-ID: <784@dms.UUCP>
Date: 18 Jul 89 14:44:51 GMT
References: <593@dtix.ARPA>
Organization: Atari Games Inc., Milpitas, CA
Lines: 25

From article <593@dtix.ARPA>, by lumsdon@tofacsa.arpa (Lumsdon):
> An Atari ST or Mega comes with a MIDI-RS232 inside. You can purchase
> such things for Amigas for less than $200. MIDI is merely a fast
> RS232 with the pins arranged into a strange looking port that
> requires a matching 2 or 3 headed plug.

	I didn't see the original question, but just couldn't let this pass.
MIDI is _not_ RS-232. It is a opto-isolated current loop. It runs 31.25K bits
per second, 8 data no parity, one stop. The RS-232 to current loop conversion
should pose no real problems for the reasonably electronically adept. The
unconventional data rate could be a real problem, unless your port provides
for "external clock". The timing resolution to _use_ MIDI could be well-nigh
impossible to achieve on a multi-tasking virtual-memory computer. Not
totally impossible, but it makes the other pieces seem trivial by comparison.

	The popular MIDI boxes for the likes of the IBM PC have internal
smarts to tag commands with time-stamps and _big_ buffers, so the PC can
get around to them at its leisure.

				Mike

| Mike Albaugh (albaugh@dms.UUCP || {...decwrl!turtlevax!}weitek!dms!albaugh)
| Atari Games Corp (Arcade Games, no relation to the makers of the ST)
| 675 Sycamore Dr. Milpitas, CA 95035		voice: (408)434-1709
| The opinions expressed are my own (Boy, are they ever)