[sdiy] Midi problems

[Scott Gravenhorst]

Of course.  I did not mean that status bytes could 
simply occur randomly.  Perhaps "unexpected" is not 
as good a word as perhaps "unnecessary".  Even that
is not a great word, since there are any number of
things a musician could do that would interfere with
the operation of running status.  This forced use
of a status byte after a period of time does indeed
fix these.  This could explain some of the quirky
looks I've had on my face when after an amount of
beer, I may do one of those "musician things".  The
keyboard stops working (mysteriously [grin]) and 
then just as mysteriously heals itself.

"Colin Fraser" <colin at colinfraser.com> wrote:
>> -----Original Message-----
>> From: owner-synth-diy at dropmix.xs4all.nl 
>> [mailto:owner-synth-diy at dropmix.xs4all.nl] On Behalf Of Scott 
>> Gravenhorst
>> Sent: 04 April 2002 6:43
>> To: synth-diy at dropmix.xs4all.nl
>> Subject: RE: [sdiy] Midi problems
>> 
>> I think that most sound modules handle an "unexpected" status
>> byte correctly because they don't "know" that a controller that
>> doesn't use running status is plugged in or not.  If a module 
>> always responds correctly to any status byte, regardless of it's 
>> otherwise legal position in the stream, needed or not, it will by 
>> default, handle those extra status bytes that occur after some 
>> arbitrary timeout.
>
>The status byte can't actually be refreshed every 100ms unless there is
>a message to be sent.
>I think the idea is that the transmitting device, if more than 100ms has
>elapsed since the last message was transmitted, will 'forget' the
>running status it is using, so that the next message it sends will be
>sure to have a status byte.
>
>Not refreshing the status is only going to cause a problem if a status
>byte gets lost.
>I guess whether refreshing the status byte is in the spec or not, it is
>still good practice to do so.
>
>Colin f
>

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