Re: MIDI spec question

In article <bvrkj15cpck3pajss069rvmcn39hj8dm1k@xxxxxxx>, martin griffith <martingriffith@xxxxxxxxxxxxx> writes 
On Wed, 28 Sep 2005 06:55:23 GMT, in comp.arch.embedded H
<user@xxxxxxxxx> wrote:

Hi,

I'm thinking about doing a MIDI project for fun and I was looking at
example circuits.

I see that many people ground PIN 2 on MIDI OUT and I'm wondering why --
pins 4 & 5 on MIDI out drive the opto-isolator on the MIDI INput side
(pins 5 & 4 respectively).

H. 
try this
http://www.avrfreaks.net/index.php?module=dpDocs&func=display&mid=94

Need to register to read it!!


The answer is - the midi spec says so. It is to ground the cable screen (if there is one) to help prevent interference getting out of the cable.
--
Tim Mitchell
.

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