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Re: TimeStamps with ischo. transfers

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.

For receive DCL programs, this is working as expected.

Can you provide a sample procedure, steps, required to do this?

Also, I'm a bit afraid of changing the flags for when the update should be run, not knowing exactly what all happens in the update.

Thanks.
Devendra.


At 02:38 AM 10/25/2005, Niels wrote:
Hi Devendra...

On Oct 21, 2005, at 9:58 PM, BlazeAudio Developer wrote:

Hi Niels,

Can you confirm two things for Send NuDCLs:

a. The update step happens before the buffer is transmitted on the wire.

b. If a is true, then, does it imply that the timestamps being copied are invalid/stale.

And if a. and b. are true, then what is the proper way of getting correct timestamps for sent packets?
The update is triggered by the DCL being "run", that is, by the packet being transmitted. (We get an interrupt from the hardware) So the update runs after the DCL is transmitted... but by default the update runs after your callback executes.. perhaps this is not what you expected? You can use the NuDCL setFlags() API to set the "kUpdateBeforeCallback" flag.. This will cause your update to run before the callback is run.

You can also run the update step manually by calling dcl->update()...

.niels


niels gabel

firewire cpu software
apple computer, inc.

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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>)



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