The Motorola DCT700 digital cable box is pretty common these days. Many cable providers are forcing its adoption in order to get access to "digital tier" programming. For MythTV users an external IR Blaster is required to control changing of channels for scheduled recordings. A remote definition will need to be added for the cable box and a channel changer script implemented to control the blaster. Fortunately this setup is relatively straightforward and problem-free. You will NOT see the STB's overlay in mythtv (but the myth overlay will obviously work just fine).
This setup was tested using the Microsoft MCE Remote and IR Receiver/Transmitter http://www.mythtv.org/wiki/index.php/MCE_Remote
Before Starting
Make sure your remote is configured and working properly in the myth frontend. You may choose from a number of preselected configurations by running the dpkg-reconfigure command. With the Windows MCE remote, pick the MCE Remote/Transmitter option and the Windows MCE/Motorola Cable box option.
Adding a remote definition for the DCT700 to /etc/lirc/lircd.conf
Once you setup LIRC for the MCE receiver/transmitter the blaster should work out of the box. You will first need to either create a remote definition using the irrecord command or use the following file (recommended. It works around the 0 issue). Simply create a file called DCT700.conf in /etc/lirc/ and copy the configuration below.
#########
#
# Modified DCT2000 entry for DCT700 (sends zeros)
# For use with the USB MCE ir receiver
#
begin remote
name DCT700
flags RAW_CODES
eps 30
aeps 100
ptrail 520
repeat 0 0
gap 100000
begin raw_codes
name bypass
9000 4400 550 2200 550 2150
550 4450 550 2150 550 4450
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 4450 550 4400
550 2200 550 4400 550
name power
9050 4400 550 2200 550 4400
550 2200 550 4400 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 4400
550 4450 550 2150 550
name help
9000 4400 600 2150 550 4450
550 2150 550 2200 550 4400
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 4450
500 2200 550 4450 550
name day-
9000 4400 550 4400 550 2200
550 2200 550 4400 550 4400
600 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 500 2200
550 4450 550 2150 550
name day+
9000 4400 550 2200 550 2200
550 2150 550 4450 550 4400
550 4400 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 4450 550 2150
550 4450 550 2200 500
name rec
9050 4400 550 4400 550 2200
550 2200 550 2150 550 4450
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 4450 550 4400 550
name stop
9000 4400 550 4400 550 2200
550 2200 550 4400 550 4400
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 4450 500 2200 550
name pause
9000 4400 550 4400 550 4450
550 4400 550 4450 550 4400
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550
name rew
9000 4400 550 2200 550 4400
550 4450 550 4400 550 4450
550 2150 550 2200 550 2200
500 2200 550 2200 550 2200
500 2200 550 4450 550 2150
550 2200 550 2200 500
name ffwd
9050 4400 550 4400 550 2200
550 4400 550 4450 550 4400
550 2200 550 2150 600 2150
550 2200 550 2150 550 2200
550 2200 550 2150 550 4450
550 2200 500 2200 550
name play
9050 4400 550 2150 550 2200
550 2200 550 4400 550 4400
550 4450 550 2200 550 2150
550 2200 550 2200 500 2200
550 2200 550 4400 550 2200
550 4400 550 2200 550
name pageup
9000 4400 550 2200 550 4400
550 2200 550 4400 550 4450
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4400 550 4450
550 2150 550 2200 550
name pagedown
9000 4400 550 4450 550 4400
550 2200 550 4400 550 4450
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 4400
550 2200 550 2150 550
name info
9050 4400 550 4400 550 4400
600 2150 550 2200 550 4400
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 4450
550 2150 550 4450 550
name menu
9050 4400 550 4400 550 2200
550 2200 550 4400 550 4400
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 4400
550 4400 550 2200 550
name guide
9050 4400 550 2150 600 2150
550 2200 550 2150 550 4450
550 4400 550 2200 550 2150
600 2150 550 2200 550 2200
500 2200 550 4450 550 2150
550 4450 550 4400 550
name lock
9000 4400 600 2150 550 4400
600 4400 550 2200 550 4400
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 2200
550 2150 550 4450 550
name exit
9000 4400 550 2200 550 4400
550 2200 550 2200 550 4400
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 2200
550 4400 550 4450 550
name up
9000 4450 550 2150 550 2200
550 4400 550 2200 550 4400
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 2200
550 2200 500 4450 550
name down
9000 4400 600 4400 550 2200
550 4400 550 2200 550 4400
550 4400 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 4450 550
name left
9000 4400 550 2200 550 4400
550 4400 600 2150 550 4450
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4400 550 4450
550 4400 550 2200 550
name right
9050 4400 550 4400 550 4450
550 4400 550 2200 550 4400
550 4400 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 4450
500 4450 550 2200 550
name ok
9050 4400 550 4400 550 2200
550 2200 550 2150 550 4450
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 4400
550 4450 550 4400 550
name ch+
9000 4400 550 4400 550 4450
550 2150 600 4400 550 2150
600 2150 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4450 500 2200
550 4450 550 2150 550
name ch-
9050 4400 550 2150 600 2150
550 4450 550 4400 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 4400 550 2200 550
name last
9000 4400 550 4450 550 4400
550 2200 550 2150 550 4450
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 4400 550 4450 500
name fav
9000 4400 550 4450 550 2150
550 4450 550 2150 550 4450
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 4450
500 2200 550 4450 500
name enter
9000 4400 600 2150 550 2200
550 2150 550 2200 550 4400
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4450 500 4450
550 4400 550 4450 550
name music
9000 4400 550 2200 550 2200
550 2150 550 2200 550 4400
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4400 550 4450
550 4400 550 4450 500
name p
9000 4400 600 4400 550 4400
550 4450 550 2150 550 4450
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 4450 550
name x1
9050 4400 550 4400 550 4450
550 4400 550 2200 550 2150
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 4450
500 4450 550 2200 550
name x2
9050 4400 550 2150 550 2200
550 2200 550 4400 550 2200
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 4400
550 4450 550 2150 550
name 1
9000 4400 550 4450 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4400 550 4450
550 4400 550 4450 550
name 2
9000 4400 550 2200 550 4400
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 4450
550 4400 550 4450 500
name 3
9000 4400 550 4450 550 4400
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550 2200
550 4400 550 4450 500
name 4
9000 4400 550 2200 550 2150
550 4450 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 4400 550 4450 550
name 5
9000 4450 550 4400 550 2200
550 4400 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 2200 550 2150
550 2200 550 4400 550 4450
550 2200 500 4450 550
name 6
9000 4400 550 2200 550 4400
550 4400 600 2150 550 2200
550 2200 550 2150 550 2200
550 2200 500 2200 550 2200
550 2200 500 2200 550 4450
550 2150 550 4450 550
name 7
9000 4400 550 4400 600 4400
550 4400 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 4450 550 2150
550 2200 550 4400 550
name 8
9000 4400 550 2200 550 2150
550 2200 550 4400 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 2150 550 2200
550 2200 550 4400 550
name 9
9050 4400 550 4400 550 2200
550 2150 600 4400 550 2150
600 2150 550 2200 550 2200
500 2200 550 2200 550 2200
500 2200 550 4450 550 4400
550 4400 550 2200 550
name 0
9000 4400 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 2200
550 2150 550 2200 550 42050
9000 2250 500
end raw_codes
end remoteOnce you have done this, be sure to add an include line in your /etc/lirc/lircd.conf file for this configuration file we've just created. Simply add the following text to the end of your lircd.conf file:
#Configuration for the Motorola DCT700 Set Top Box IR codes: include "/etc/lirc/DCT700.conf"
Testing the Remote definition and blaster
Restart LIRC:
$ sudo /etc/init.d/lirc restart
Next we'll test to see if the remote keys are defined correctly:
$ irw
You should see output for all the remote buttons you press.
Next we'll trying getting the blaster to do something on the cable box:
$ irsend SEND_ONCE DCT700 info
You should see the emitter on the blaster light up. If it blinks then we're in business. Don't panic if the cable box didn't do anything. The cable box is very picky as to where the IR receiver is located. Try issuing the following command which will repeatedly send the command to the blaster:
$ irsend SEND_START DCT700 info
The emitter is now sending a continuous stream of pulses. You will need to move the blaster around until you find the sweet spot. It will be similar to this:
Once it’s working you can stop the pulses by issuing the following command:
$ irsend SEND_STOP DCT700 info
Next try to change the channel to 151 (or some other channel) via the following command:
$ irsend SEND_ONCE DCT700 1 5 1
Finally try powering the cable box on and off:
$ irsend SEND_ONCE DCT700 power
Create a change channel script
You will need to create a script called change-channel.sh and add it to /usr/local/bin and later add this to the "channel change script" entry in the Input Connections section of "mythtv-setup".
REMOTE_NAME=DCT700
cmd="$1"
case $cmd in
[0-9]*)
for digit in $(echo $1 | sed -e 's/./& /g'); do
irsend -d /dev/lircd SEND_ONCE $REMOTE_NAME $digit
sleep 0.2
# If things work OK with sleep 1, try this for faster channel changes:
# sleep 0.3
done
irsend -d /dev/lircd SEND_ONCE $REMOTE_NAME OK
sleep 1
irsend -d /dev/lircd SEND_ONCE $REMOTE_NAME EXIT
;;
*)
irsend SEND_ONCE $REMOTE_NAME $cmd
;;
esac"Note:" Moving the send of EXIT to before the loop over digits may give you success for channels 3 digits in length. That also may solve an issue with some of the first digits being dropped. It seems that the EPG from Comcast needs to be exited first before entering digits.
After you've created the file with your text editor of choice and then modify the permissions to make it executable by all users.
$ sudo chmod +x /usr/local/bin/change-channel.sh $ sudo chmod 775 /usr/local/bin/change-channel.sh
As an alternative, the old channelchange.pl has been rewritten for the updated lirc files.
Again, you can access it at http://kin.bounceme.net/channelchange.pl
############################################################
# File - channelchange.pl
# Author - Guardian Bob
# Date - Tuesday, August 07, 2007
# E-Mail - Guardian.Bob@gmail.com
# Description - Changes channels.
# Changelog - August 07, 2007
# Initial Revision
#
# August 19, 2007
# Adjusted the sleep (0.2->0.3) as at
# 0.2 two 5 commands were treated as 1.
# Starting each channel change with a
# ch+ to try to bring the box out of
# a standby mode (sometimes the box
# ignores the first command sent.)
#
# April 28, 2010
# Now that someone fixed the 0, updated
# the script for better performance.
############################################################
use strict;
use constant IRCMD => "/usr/bin/irsend SEND_ONCE DCT700 ";
use constant SLEEP_CMD => "/usr/bin/sleep ";
use constant WAKEUP_DELAY => SLEEP_CMD . "1; ";
sub ChannelCmd
{
my $chan = shift();
if(length($chan)==0)
{
# double ok/exit combo needed to hide OSD.
return "ok ok exit exit; ";
}
my $digit = substr $chan,0,1,"";
return $digit . " " . ChannelCmd($chan);
}
my $channel = int($ARGV[0]);
# tried exit, that didn't work correctly, so used info
my $cmd = IRCMD . "info " . ChannelCmd($channel);
# Build the cmd and print it
# Add the exit command and wait a second to process it, as the box can
# sometimes ignore the first command sent.
# Debug line, should put in option processing at some point.
#print IRCMD . "exit; " . WAKEUP_DELAY . $cmd . "\n";
exec IRCMD . "exit; " . WAKEUP_DELAY . $cmd;This script should not suffer from threading issues.
Comcast On-Demand
The On-Demand button on the stock Comcast remote simply sends a 0 followed by Enter. As such, it should be possible to access On-Demand through MythTV, although there are a few caveats.
First, it should be noted that in order to cleanly exit from on-demand, an Exit signal *MUST* be sent or the DCT700 will automatically tune back to On-Demand.
Second, while on channel 0, certain functions from the remote that would ordinarily be processed by the frontend must be delegated to the DCT700. At a minimum, these functions must be passed to the IR blaster: arrow keys, ok, and exit commands.
If anybody can edit the change-channel.sh script to add this functionality, it would be greatly appreciated.
Third and last, it is likely useless to incorporate the pause, rewind, and fastforward features in On Demand. For one, they're absolutely horrible and unresponsive, and second, since the mythtv backend will be recording the On-Demand program, playback can be controlled in that manner. It also remains to be investigated whether or not mythtv can properly flag commercials in On-Demand, though there is no reason to suspect it shouldn't.
Known Issues
As of right now, there seems to be a problem calling the channel change script when manually entering a channel number in livetv that is two digits or greater. Changing channels from the program guide still works.
This issue seems to revolve around the script changing to the desired channel, but then changing (twice) to a channel corresponding to one of the digits entered.
Below is an irw output for the issue:
# Tried changing to channel 25 with MCEUSB by typing 2, 5, OK 000000037ff07bfd 00 Two mceusb 000000037ff07bfd 01 Two mceusb 000000037ff07bfa 00 Five mceusb 000000037ff07bdd 00 OK mceusb 0000000000000022 00 2 DCT700 0000000000000025 01 5 DCT700 0000000000000017 02 ok DCT700 0000000000000012 03 exit DCT700 0000000000000022 04 2 DCT700 0000000000000017 05 ok DCT700 0000000000000012 06 exit DCT700
Below is a log file generated by adding the following line to the script:
echo "Changing channel to $cmd" >> ~/channel-change.log
# Attempted to change to channel 32 by typing 3, 2, OK Changing channel to 32 Changing channel to 2 Changing channel to 2 Changing channel to 2 Changing channel to 32 Changing channel to 3 Changing channel to 19 Changing channel to 25 Changing channel to 2