This doesn't answer your question, but I put a safety mechanism in my
Firewire DCL program
(actually NuDCL program) where if an overrun occurs, I do a self loop
on the last buffer to
prevent an actual overrun.
So I have a 3 buffer safety zone as the documentation suggests, and
with the 3rd buffer,
at the end I jump back to the beginning of the 3rd buffer.
If the hardware gets too far ahead of the software, the hardware is
then held in check.
That way in the event of an overrun (which happens from time to time
on my G4), things don't
fall apart, I just lose a couple frames (video frames, in my case),
and then things go back
to normal.
And then with each callback, I move the 3 buffer zone forward 1, and
adjust my jumps appropriately.
Tommy
*************************
Message: 1
Date: Tue, 18 Oct 2005 09:30:17 -0400
From: Philip Lukidis <email@hidden>
Subject: listen DCL program woes
To: email@hidden
Message-ID: <79710AF8DF7794458457EAF404E82431053E7B68@GCMTLEXC>
Content-Type: text/plain; charset="iso-8859-1"
Hello. I have problems with my listen DCL program, in that it
eventually
stops running (callbacks cease, as least). It has the overrun detection
system as discussed in the isoch DCL html document (if the overrun
proc is
called, it means that the jumps were not modified in time, and
overrun has
occurred). I do not believe that overrun has occurred, though, due to
driver debug output, and that it does not occur on some slower machines.
This problem occurred after many hours only. It seems that my play DCL
callbacks are being called, though. Unfortunately I don't know if a
fatal
OHCI error occurred (handleUnrecoverableErrorInt) because the IOLog is
swamped with debug output (firelog was not on at the time).
Is there any other reason for a DCL program callbacks to stop being
called?
Unfortunately I didn't have debug OHCI installed, and so I cannot use
mr.
registry to any effect. I have listed my DCL program below.
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