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Re: Midisport and sysex

On Dec 21, 2004, at 12:41, Herbie Robinson wrote:
I found it necessary to sleep for several seconds after initializing MIDI or else data got lost. It wasn't driver specific. The problem is that the USB devices essentially initialize asynchronously and often aren't there for a few seconds.

Do you mean that the devices don't show up with MIDIGetDevices (and MIIGetSources/Destinations too) right away? Or do they do show up but fail to communicate unless you wait awhile first?

I've seen the USB toggle problem Pete spoke of with at least one non-M Audio device, but that's a different ball of wax.

One of the reasons it would be better to leave the MIDI Server running all the time.... 

Two problems with that:

[1] A misbehaving driver can crash the server which in turn makes it necessary to restart all the clients. Someday I'd like to make the client-side code able to handle this transparently to the app, but it's tricky business.

[2] Long-running processes are bad for overall system performance; they consume resources.

I wonder if it's feasible for drivers to defer marking a device as online until it knows that I/O will succeed.

Doug

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References: 
 >Midisport and sysex (From: "Peter Karlsson" <email@hidden>)
 >Re: Midisport and sysex (From: Herbie Robinson <email@hidden>)



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