Re: MIDI spec question



On Wednesday, in article
<MPG.1da3de1e82c122849897a2@xxxxxxxxxxxxxxxxxxxxxx>
user@xxxxxxxxx "H" 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.

>From my recollection of the MIDI spec is ONLY ONE end should ground
the shield of the cable. Thus keeping isolation if optos are used but
maintaining some shielding without ground loops.

Then again it is several years since I looked at MIDI circuits.

--
Paul Carpenter | paul@xxxxxxxxxxxxxxxxxxxxxxxxxxx
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.



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