[mythtv-users] channel changer script too slow?

Nick Morrott knowledgejunkie at gmail.com
Sat Apr 21 19:56:03 UTC 2007

On 21/04/07, Kurt Yoder <ktymyth at yoderhome.com> wrote:
> Hi list
> Has anyone ever encountered a channel changing script that is
> sometimes too slow?
> I have a Verizon set top box and an IR blaster off a Hauppauge 150.
> Occasionally the channel changer will change too slowly on a 3-digit
> channel and I will end up on the wrong channel number. For instance
> if the channel is 485 I will see the channel change first to 48, then
> to 5. I suppose there are two possible approaches: make the STB wait
> longer before changing channels, or make the channel changer script
> send its keys more quickly. Has anyone else managed to do either one
> of these?

I've noticed whilst using a couple of homebrew serial IR blasters for
the past couple of years that sometimes the STB just doesn't register
a digit (often the last digit). On my cable service (VirginMedia in
the UK) all bar one channel has a three digit number, so if a code is
not received correctly, the channel usually fails to change at all.

I've tinkered with the timings of the key sends and this has helped
somewhat, but I do still see this from time to time, even on our newer
STBs. Apparently the older Pace cable boxes we had had a known fault
whereby the IR buffer on the STB would not clear out, which would
result in lost key presses from either the regular remote control or
the IR blaster. The STB would require a regular reboot to fix this.

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