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Re: TimeStamps with ischo. transfers

At 10:03 AM +0530 10/25/05, BlazeAudio Developer wrote: 
Hi Niels,

Okay, I'm getting a bit confused here now!

Perhaps I should ask a simple question:

When I do the callback processing, I need to know the time when the last packet (which was sent before the callback) was transmitted.

Depending on your program, the time stamp may be in the future. The FireWire stack calls you back before the last packet is transmitted. I have seen about a 200µS time stamp in the future when looking at the current FireWire time and the timestamp.

I think relying on timestamps or other events after the fact are problematic. You need to take it by faith that the packets go out when you scheduled them to. If they don't, an error will be reported and then you can deal with the error. If they don't go out when you expect, you have a serious problem on your hands and audio is going to glitch.



Matt
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References: 
 >RE: TimeStamps with ischo. transfers (From: Philip Lukidis <email@hidden>)
 >Re: TimeStamps with ischo. transfers (From: Niels <email@hidden>)
 >Re: TimeStamps with ischo. transfers (From: BlazeAudio Developer <email@hidden>)
 >Re: TimeStamps with ischo. transfers (From: Niels <email@hidden>)
 >Re: TimeStamps with ischo. transfers (From: BlazeAudio Developer <email@hidden>)



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