Re: of timestamps & midi packets
Re: of timestamps & midi packets
- Subject: Re: of timestamps & midi packets
- From: Philippe Wicker <email@hidden>
- Date: Thu, 31 Jul 2003 20:06:30 +0200
On Thursday, July 31, 2003, at 06:40 PM, Roy Lovejoy wrote:
>
Before I start padding my office, and removing sharp objects &
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shoelaces,
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can someone please tell me if the timeStamp field in the MIDIPacket
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datastructure
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is used during a MIDISend() ??
Yes, it is. You can keep your shoelaces :-))
>
>
the data I was sending down sounded like a 50 car pile-up, so I
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reduced the test
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case down to a note on & a note off, the first with a timestamp of
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AudioGetCurrentHostTime(),
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the second with a time stamp of that, plus a rather big number, and
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the sound out of the midi device
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was still just a blip (not on for any perceivable duration).
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>
with MIDISend(), do _I_ need to sequence everything, or does timeStamp
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really mean something?
The time unit (see a little bit further) is very very small, so a
"rather big number" may still be a rather short time :-)
>
>
And though I'm a MIDI newbie (this time around.. did the whole MIDI
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Manager thing, back in the day),
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I always do google/adc research before posting on any list, but i'll
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be d@mned if I couldn't find a single reference that said what unit
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MIDITimeStamp was in. (milliseconds? microseconds? MTC?)
The time unit is a division of the cpu clock tick (depends on the
machine and I've been said it is a function of the bus clock, something
around 1/20th for my DP867, don't remember exactly). To determine the
actual value of this clock tick call AudioGetHostClockFrequency().
>
>
any and all help appreciated.
>
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Philippe Wicker
email@hidden
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