Using an IR Blaster with MythTV
by Robert Wamble
NEW: I've recently updated the HOWTO for Fedora Core 5, kernel 2.6.17, and lirc-0.8.1pre1.
The mission was to get MythTV to use my Actisys IR-200L blaster to change channels on my Motorola DCT2244. Since MythTV uses lirc for its remote control, and lirc has not (for me) easily handled two devices simultaneously, I had to get an independent lirc running to drive the blaster. To do this, I followed the recommendations found in mythtv-users postings by Sriram Balakrishnan, Gary Te Young, and Mike Smith.
The HOWTO and accompanying scripts comprise my attempt to steamline the process for others. While I can only say that this works for my setup, hopefully it will be helpful with other hardware combinations.
A download link is available at the page above for an already converted remote* package, so that you can skip the script based process of converting lirc* to remote*. There's also a link to a channel.pl that handles 4 digit channels.
Alternative IR Blaster HOWTO
IR Blaster Setup without compiling second instance of LIRC
This is an IR Blaster setup guide primarily meant for FC3 users who followed Jarod Wilson's setup guide. With this version, a second install of LIRC is not needed. All necessary components can be downloaded from atrpms.net via apt-get (which will already be done if Jarod's guide was followed). This means that no compiling is necessary. Simply editing a few files is enough to achieve this. This is especially useful for FC3 users, as kernel source is no longer included with that linux distribution.
Note that MythTV sends frequency IDs to the external channel changer script and not the channel number. If you see some weird four/five digit numbers being sent through the IR blaster, you will need to go to the channel editor in setup and change the freqid for the channels to match the ones that you expect to receive through the IR blaster.
Note: You can get MythTV 0.20 to send out channel numbers as the parameter. First, get EPG working. Then using, mythtvsetup, channel-editor, remove all your channels. To add the channels again, this time, instead of scanning for channels, get the channel list from the epg service and readd those channels.
Alternative setup that does not require LIRC
If you prefer not to have to mess around with LIRC there are alternatives. One of these is the MyBlaster serial. (See the vendor list below.) It is a commercial product but the linux drivers are GPL. The latest driver can be found on SourceForge. To set up, simply edit the perl based driver script for your port and device and call the script using the external channel change script configuration option in mythtv-setup. It is that easy.
IR Blaster Vendors
In the USA
Mythblasterz offer an inexpensive IR blaster with 5+ meter range.
IRblaster offer serial port IR blasters, as do:
MyTVStore sells the MyBlaster products.
IguanaWorks also sell IR blasters.
Dvbshop.net sell IR remotes, receivers & blasters
IRtrans sell IR transceivers (combined receiver/blaster) & LAN equipped units too