[sdiy] MIDI opto-isolator

[Rob B]

The most I have ever seen go wrong when using different optos is that you
sometimes have to adjust out the trigger points because they are
asymmetrical and you get some flakey pulse widths.

That usually doesn't happen with the pc900.

rob


AIM: cybrgzr0 <--- the last thing is a number
----- Original Message -----
From: "Hallvard Tangeraas" <northstar2010 at yahoo.no>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Monday, November 26, 2001 6:59 PM
Subject: Re: [sdiy] MIDI opto-isolator


> At 07:01 -0800  26.11.01, GothGeek Sysadmin wrote:
>
>
> >On Mon, Nov 26, 2001 at 02:44:54AM +0100, Hallvard Tangeraas wrote:
> >> I need some help in identifying an opto isolator used in the Atari STe
> >> computer for the MIDI IN port.
>
> >There are copies of the Atari schematics at :
> >http://www.fortunecity.com/skyscraper/quadra/455/
>
> Yes, I've downloaded the STe schematics from this site, but it was
> rather fuzzy, and the writing was hard to make out.
>
>
> >Sure enough the 1040STe uses the PC900.
>
> Yup, sounds about right as the text in the schematic looked like PC-800
> or PC-900. As Peter Ullrich also pointed out that it's a PC-900 and
> someone else (with yet a different source) said the same thing it's
> settled.
>
>
> >Should be able to compare the schematic to the board to verify that
indeed
> >it is a PC900 from some other source...
>
> Well, the one on the board wasn't a PC-900 as I've pointed out, but
> must of course be a compatible, so that's good enough for me as I just
> wanted to know the pinouts anyway (and I have the data for the PC-900
> here).
>
> Thanks everybody!
>
>
> Hallvard
> --
> Notator/Creator SL : <http://www.notator.org>
> Atari Launchpad    : <http://launchpad.atari.org>
>