133 lines
4.9 KiB
Plaintext
133 lines
4.9 KiB
Plaintext
From: ttl@aura.cs.wisc.edu (Tony Laundrie)
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Subject: Re: Radio Shack Secret? (Midi cables)
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Date: 8 Aug 91 17:38:55 GMT
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> (From Bob McQueer's MIDI Spec Primer)
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>
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> The standard connectors used for MIDI are 5 pin DIN. Separate sockets
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> are used for input and output, clearly marked on a given device. The
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> spec. gives 50 feet as the maximum cable length. Cables are to be
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> shielded twisted pair, with the shield connecting pin 2 at both ends.
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> The pair is pins 4 and 5, pins 1 and 3 being unconnected:
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>
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> 2
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> 5 4
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> 3 1
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If you buy a generic cable, it probably looks like:
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/\ ################# /\
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1 -|------#################---|------ 1
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| | ################# | |
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2 -|------#################---|------ 2
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| | ################# | |
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3 -|------#################---|------ 3
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| | ################# | |
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4 -|------#################---|------ 4
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| | ################# | |
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5 -|------#################---|----- 5
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| | ################# | |
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\/ ################# \/
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\___/ SHIELD \___/ Metal Shell of DIN Connector
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This probably works, but it might be electrically noisy, and perhaps not
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reliable for long distances. If you make your own cables with 2-conductor
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shielded wire as described in the SPEC, do it as shown below:
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/\ /\
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/\ / ################# \ /\
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1 -|- | | ################# | | ----- 1
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| | | ################# | | |
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2 -|-----/ ################# \--|------ 2
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| | ################# | |
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3 -|- | ################# | ----- 3
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| | ################# | |
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4 -|----------#################-------|------ 4
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| | ################# | |
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5 -|----------#################-------|----- 5
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| | ################# | |
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\/ ################# \/
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\_ SHIELD _/ Metal shell of DIN Connector
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Connect the wire shield to pin 2, and connect pins 4 and 5 with the other
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wires. Do NOT connect the metal shell of the DIN connector to the wire
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shield (pin 2) -- I had pin 2 shorted with the shell at first and that
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didn't work with my setup.
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ttl@cs.wisc.edu
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From: janin@v785.stanley.co.jp (chan" Janin)
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Subject: Re: MIDI DIN connector pin-out needed
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Date: 7 Jan 92 10:18:06 GMT
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************************************************************************
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* Please Please, Refrain from "Email"-ing me... Look at my Signature ! *
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************************************************************************
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In article <311@ittc.wec.com> simmons@ittc.wec.com (Gary Simmons) writes:
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>A friend got a Soundblaster for Xmas and wants to make his own cable
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>to go between the 15 pin connector on the SB card to a MIDI connector
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>on the other. What pins do what on the MIDI end? I remember a bit of
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>discussion on this a while back, but didn't save any of it...
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>
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>Thanks,
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>
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>Garry Simmons
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>simmons@ittc.wec.com
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I hope nodoby replied you before me...
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This is the TRUE pin assignment for MIDI plugs.
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I know it "by heart" because I used to make my own interfaces
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for my computers...
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MIDI IN : 1- n.c.
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4- anode of optocoupler
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2- n.c. <<<--- !!!! Different for MIDI OUT
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5- cathode of optocoupler
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3- n.c.
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MIDI OUT/THRU: 1- n.c.
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4- +5v thru resistor
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2- local ground
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5- TTL open collector ouput
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3- n.c.
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The pin numbers are usually printed into the plastic of the plug,
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in that order (or the reversed one).
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Don't connect MIDI IN pin 2... it preserves OPTOISOLATION from
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MIDI OUT device to MIDI IN device.
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To make your own MIDI cable, wire pin 4 to 4, pin 5 to 5, pin 2 to 2
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and to the shield of your cable.
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------------------------------------------------------------------------
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Pascal JANIN -Amiga & Anime Addict Forever | "Buki! Buki!" Pi-chan says
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< STANLEY ELECTRIC CO. LTD, R&D LAB 71G > | // My 1st computer: DAI
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< Fax: 81+ 45-9110007 (045-... from Japan> | \ // My current 2nd:Amiga
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*** I can r/w E-mail ONLY inside Japan *** | \X/ ...ONLY the bests !!
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*** Sorry, you'd fax or use "F" option *** | Discard all Pee-Cee users !
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------------------------------------------------------------------------
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From: smill@polari.online.com
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Subject: Re: Now what? (MIDI)
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As stated in the MIDI 1.0 Spec:
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"The cable shall be twisted pair, with the shield connected to
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pin 2 at both ends."
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^^^^^^^^^^^^
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The ground loop problem is dealt with in the fact that MIDI
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jacks on instruments are specified as pin 2 (ground) being connected
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only at the transmitting ends, not at receiving end. This allows cables
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to be used in any situation, with the ground connection taken care of
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in the hardware specification.
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--
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Steven M. Miller "The history of music evolution is
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smill@polari.online.com not the history of nice guys"
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-- Anthony Braxton
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Electronic Music Coordinator - Cornish College of the Arts, Seattle WA
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