[mythtv-users] recent dish external channel change problems?

Jim Stichnoth stichnot at gmail.com
Sun Dec 6 15:30:46 UTC 2009

On Sun, Nov 29, 2009 at 9:11 AM, Jim Stichnoth <stichnot at gmail.com> wrote:
> On Sun, Nov 29, 2009 at 8:12 AM, Alex Williamson
> <alex.l.williamson at gmail.com> wrote:
>> I've been using a dish vip211 with an IguanaWorks serial IR
>> transceiver for most of the year with very high reliability on channel
>> changes.  Recently, my channel change reliability has taken a nose
>> dive.  I've played with my channel change script, increasing delays
>> between commands, but I can't find a recipe that gets me back to the
>> reliability I had earlier.  I typically get double button presses, so
>> instead of tuning to channel 138, it might tune to channel 113, which
>> doesn't exist in my lineup, sending me into the hard to get out of
>> menus.  I've had to resort to using the dish guide to change channels
>> to avoid this.
>> I notice that http://dishuser.org/211sw.php lists that dish released a
>> new firmware image for this system on 11/5/2209 (L527), which seems
>> like it roughly coincides with when my channel change issues started,
>> but my receiver claims to be running software version L458.  I'm
>> running mythtv 0.22.0+fixes22890, but I suspect the issue is
>> independent of mythtv as I get the same results manually running the
>> channel change script outside of myth.
>> Is anyone else having recent issues with dish receivers?  Is there an
>> IR transmitter that's more reliable than serial, perhaps a USB-UIRT?
>> Thanks,
> I also have a vip211, running the L527 firmware.  Over the past 2
> weeks or so, I started noticing some occasional problems with channel
> changing and also with HD-PVR recording.  I wouldn't say that channel
> changing reliability has taken a nose dive, but it used to be rock
> solid and now there are occasional problems.  When it fails, it
> usually ends up tuning into some infomercial channel (not sure which
> one).  I didn't realize there was a firmware update, but now that I
> know, I can try experimenting with my channel changer script.

I experimented some more using live TV, and I found something that
seems to make channel changing much better than before, almost
perfect.  Try changing the SEND_ONCE commands into a SEND_START,
followed by a short sleep, followed by a SEND_STOP, followed by
another short sleep.  If anyone tries this, please write back about
whether that improves channel changing accuracy.

For reference, below is my script.  Note that the entire execution is
wrapped in a "( ... ) &" construct so that the setup of the recording
can continue without delay.  As a side effect, the channel changing
sequence gets recorded as well.  This can be nice for troubleshooting,
or annoying for playback.



transmit() {
    #irsend -d /dev/lircd SEND_ONCE dish $1
    irsend -d /dev/lircd SEND_START dish $1
    sleep .1
    irsend -d /dev/lircd SEND_STOP dish $1
    sleep .1

# Send the "down" button in case the receiver is tuned to an unsubscribed
# channel, in which case it will only respond to an up or down arrow.
transmit down

# Send the "select" button in case the receiver has recently downloaded
# the nightly program guide or whatever.
transmit select

# Send the digits one by one.
for digit in `echo $1 | sed 's/\(.\)/\1 \n/g'` ; do
    transmit $digit

# Send "select" to commit the channel change now instead of
# waiting for the timeout.
transmit select

# Send "cancel" to clear the on-screen display.
transmit cancel
) &

More information about the mythtv-users mailing list