Difference between revisions of "Using an IR Blaster with MythTV"

Revision as of 14:39, 24 February 2007

Introduction

[1].

by Robert Wamble

Hopefully Robert will fix these links. Meanwhile, See the alternative section for working links and a good HOWTO.

Current Location of IR Blaster Howto and various files: [2]

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

Andy's HOWTO is the easiest to follow, but is Fedora specific. It says Fedora Core 3, however I have used it on Fedora Core 4, and it should work for most Fedorae.] It expects that Myth has been setup according to Jarod Wilson's Guide.

A second IR BLASTER HOWTO has been posted to [3] with a mirror at [4]

If you have a Hauppauge PVR-150, it may include a built-in IR output capability. See Hauppauge PVR-150.

IR Blaster Setup without compiling second instance of LIRC

Troubleshooting

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.

When using the script and setup at http://losdos.dyndns.org:8080/public/mythtv-info/IR-BLASTER-HOWTO.html

• do not* be tempted to change the configure options to set COM1/IRQ4 in the pre-make configuration. Rather, follow the directions and pass those options through /etc/modules.conf or /etc/modprobe.d/aliases.

Changing the settings at the earlier stage will produce a module that conflicts with the standard lirc (and a frustrating string of errors in dmesg: ledxmit_dev: register_chrdev failed ledxmit_serial: Unknown symbol ledxmit_register_plugin).

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.

In Canada

CommandIR sells a hardware-based USB multi-blaster. Available in Canada and the US.

In Europe

Dvbshop.net sell IR remotes, receivers & blasters

IRtrans sell IR transceivers (combined receiver/blaster) & LAN equipped units too

RedEyeRemote They don't look much, but these IR transmitters work via serial port with NTL PACE and Samsung STBs.