Any counter-indications to use hdpvr-killer to keep hdpvr off?

[dborn]

Gavin,

I want to try something to avoid the lock ups (instead of reacting
when it's too late to save the recording).

I was planning on switching off my stb and hdpvr while no recording or
live tv is going on and switching them on both when needed.
Would there be any counter-indications in using your hdpvr-killer to
keep my hdpvr in the off state for extended periods? I believe the on-
board relay remains energized while in the "hdpvr off state".
Would the power draw on the usb port be a problem? or keeping the
relay energized?

It seems my hdpvr locks up because it's not closing properly on the
previous recording. If I keep it off in between use (except for back-
to-back recordings of course!), I'm hoping it would all but eliminate
the problem.

I'm using udev rules for my video* devices so the disappearance/
reappearance of /dev/hdpvr shouldn't cause problems either. Would the
mythtv scheduler have a problem if the device isn't present when it
runs?

Thoughts?
Daniel

[A. McDermott]

On 12-05-09 08:06 AM, dborn wrote:
> Gavin,
>
> I want to try something to avoid the lock ups (instead of reacting
> when it's too late to save the recording).
>
>

I don't have a solution to offer, but would like to ask how you'll
determine when the backend is not going to be recording... The reason
that I ask is that I want to power cycle the HDPVR once a day, but have
not found a way to determine when the next recording is. I did try
speaking the backend protocol directly, but it appears that the start
times returned by QUERY_GETALLSCHEDULED does not include valid times.

Here is what I do:

echo "30 MYTH_PROTO_VERSION 72 D78EFD6F
28 ANN Monitor xxxxxxxxxxxx 0
22 QUERY_GETALLSCHEDULED
6 DONE
" | nc localhost 6543

I do get data back, but all the start times are the same.

[Gavin Hurlbut]

On Wed, May 9, 2012 at 7:06 AM, dborn <born_...@yahoo.com> wrote:
> Gavin,
>
> I want to try something to avoid the lock ups (instead of reacting
> when it's too late to save the recording).

I think (so far) the best idea is to increase airflow around the HDPVR
as it seems to be heat-related.

> I was planning on switching off my stb and hdpvr while no recording or
> live tv is going on and switching them on both when needed.
> Would there be any counter-indications in using your hdpvr-killer to
> keep my hdpvr in the off state for extended periods? I believe the on-
> board relay remains energized while in the "hdpvr off state".
> Would the power draw on the usb port be a problem? or keeping the
> relay energized?

I don't think it would be a problem. The relay coil draws 40mA at 5V
to remain on, and USB is designed for up to 100mA. I wouldn't expect
an issue.

[dborn]

My plan was to use the system events:

Using the event that says "going to start a recording in a
minute" (can't remember the name right now), I would power up the stb
and then power up the hdpvr, if they're not already up (see next
event).

Using the event that says "done recording", I would start a script
that waits for a few minutes and then if no new recording is coming up
within the next minute (see previous event), I'd turn off both the
hdpvr and stb. Since recordings tend to be on half-hour marks, it
should be fairly safe.

In your case, you could do something even simpler: keep a timestamp of
the last reboot and in the "going to record in a minute" event, check
to see if it's been at least 24 hours and if so, restart your hdpvr.
You might want to be sure you're using udev rules for your hdpvr
because it's likely that if you have other tuners, your /dev/video0
device might come back up as /dev/video2. It's happened to me but now
I record on /dev/hdpvr.

HTH,
Daniel