[mythtv-users] mythbackend channel change issues

Bill Meek keemllib at gmail.com
Sat Jun 11 19:49:48 UTC 2022


On 6/10/22 08:09, John Hoyt wrote:
> On Sun, Jun 5, 2022 at 10:12 AM John Hoyt <john.hoyt at gmail.com> wrote:
> 
>> Recently I've been having a random error where my STB records the wrong
>> channel.  I thought the error was on the STB side and tried to modify my
>> channel change script to accommodate new STB features (unsuccessfully of
>> late).
>>
>> Upon digging into the problem deeper, I've discovered that mythtv seems to
>> be semi-randomly sending 8 digits to the channel change script vs the 4
>> I've set it up to (caught by logging looking at the lirc logging in
>> syslog).  For example, if the channel was supposed to be 0685, mythbackend
>> would provide 00668855.
>>
> 
> Digging into this further this morning, I've eliminated the channel change
> script by adding syslog outputs to the script.  Running as a user, the
> script only ever sends commands once.  The only time I see the double send
> is when mythbackend commands it.
> 
> What I've found is that the channel change script is somehow getting called
> twice as I'm seeing two messages indicating that the script was called in
> syslog (see "Attempting to change channels lines").
> 
> If I've tracked the issue down (if I am guessing right) to lirc trying to
> perform both commands interleaved.  In the log output below, the two
> "Sending: SEND_ONCE Motorola_QIP6200-2 KEY_EXIT" demonstrate this as I send
> the "EXIT" key to way up the STB from it's standby state.  In the script, I
> only issue "EXIT" once then move on to channel changes.
> 
> Could this be a bg in mythbackend?  If not, any thoughts on what could be
> issuing the second channel change command?
> 
> Any thoughts on a way to lockout lirc / irsend to only accepting one
> command at a time?
> 
> In the log below, I've highlighted what I believe to be the repeated /
> interleaved irsend requests.
> 
> Thanks as always for the help!
> John

To prove it's coming from the backend, try: mythbackend --setverbose system:debug
You'll see all system events start and end and return code. Leave off the :debug
to get less. Use system:none to stop the extra logging.

-- 
Bill


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