[mythtv-users] Firewire fleeting on SA3250HD

[John P Poet]

I have been struggling to get *reliable" firewire communication
between my computer and my SA3250HD cable box.  I got it working last
night, and scheduled a half dozen shows to record on different
channels, throughout the night.  They all recorded just beautifully.

Today I noticed a recording start up, and the SA3250HD trying to
change channels but it went to the wrong one.  I stopped the recording
and changed the channel myself.  Then I tried to capture via
test-mpeg2 but got a zero length file.  After about 30 minutes of
randomly trying things, I got the firewire to work again.... for a
while.  A few hours later it was out of sync, again.

If I use 1394commander to reset the bus, and use plugctl to prime the
bus, and get the channel changed to a good one, and use test-mpeg2, I
can get eventually get a valid video stream.  Once test-mpeg2 is
working, I can start myth backup and it will work -- for a while.

I have not been able to figure out the sequence of events needed to
get the 1394 bus resynchronized when it looses it.  Sometimes just
resetting the bus is enough.  Other times it seems like various
combinations of plugctl and test-mpeg2 are necessary.

I get the impression that people with Motorola boxes have a bit more
success with this, than those of us with Scientific Atlanta boxes.

The very first time I ever successfully captured video via firewire,
It was after I followed Allan's directions here:

http://www.gossamer-threads.com/lists/mythtv/users/209409#209409

Unfortunately, those instructions do not work every time.

Since I cannot remember where I got it, I am attaching the version of
sa3250ch.c that works (most of the time) for me.

John
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