LIRC

The driver and/or the device for the LIRC service may need to be specified in order to run properly. Look for messages like these in the journalctl output if the service abruptly stops while running LIRC-dependent programs such as irrecord:

Driver `devinput' not found or not loadable (wrong or missing -U/--plugindir?).
readlink() failed for "auto": No such file or directory

Set these in the configuration file and then restart the service.

Modern kernel has serial_ir module, which supersedes older lirc_serial driver. It supports even DIY receivers and transmitters, connected to the motherboard's serial port. Install and run:

# setserial /dev/ttyS0 uart none
# modprobe serial_ir

After loading serial_ir module, device /dev/lirc0 will be created by kernel. If not, run as root and check for errors. An LIRC configuration example for serial device:

Sound card with connected external DIY circuits can be used to receive and transmit IR codes.

audio_alsa driver included in , but supports only reception.

Unmute microphone input with and set enough gain. You can check waveform and gain with . There should be distinguishable square pulses: not flatlined, nor overloaded. Also good demodulated pulses easily perceptible by ear. Note that LIRC and reads positive pulses in right audio channel. Negative pulses will not work.

audio driver included in and supports both reception and transmission. Note, that default latency around 0.02 can cause "Warning: Output underflow" and corrupted transmission - receiver will not respond to it. Try a higher value like 0.05.

Increase sound card output loudness, otherwise LED signal will be weak and range is low. LED flash can be detected with smartphone camera, as it sensitive to infrared wavelengths.

/etc/lirc/lirc_options.conf

driver          = audio
device          = ALSA:default@48000:0.05

Directory contains system-wide configuration files for remotes. Each *.conf file corresponds to one device and describes it's protocol, scancodes and keycodes. It allows LIRC receive and send signals for specific hardware. These files are not included in package and should be found somewhere or created by user.

Plenty of configuration files can be found in the LIRC remotes database. Follow the url or use to search the database.

An example using to find a configuration file for a "Streamzap" remote:

$ irdb-get find stream
atiusb/atiusb.lircd.conf
digital_stream/DTX9900.lircd.conf
snapstream/Firefly-Mini.lircd.conf
streamzap/PC_Remote.lircd.conf
streamzap/streamzap.lircd.conf
x10/atiusb.lircd.conf

$ irdb-get download streamzap/streamzap.lircd.conf 
Downloaded sourceforge.net/p/lirc-remotes/code/ci/master/tree/remotes/streamzap/streamzap.lircd.conf as streamzap.lircd.conf

Once identified, copy the needed conf to to allow the daemon to initialize support for it.

# cp streamzap.lircd.conf /etc/lirc/lircd.conf.d/

Remote control configurations can be created using irrecord(1), which guides users trough the process. If using a detected remote, invoke it like so:

# irrecord --device=/dev/lirc0 MyRemote

The program will instruct user to begin hitting keys on the remote in an attempt to learn it, ultimately mapping out every button and it's corresponding scancode. When finished, save the resulting file to /etc/lirc/lircd.conf.d/foo.conf and proceed. Consider sharing configuration file with others.

Bind keycodes to application-specific actions by placing their respective configuration files in which should be created manually if desired, see . This only works for LIRC-aware applications, like MPlayer, VLC, MythTV and (Kodi also supports LIRC but does so in a non-standard way, see Kodi#Using a remote control).

Define these application-specific configurations in separate files and include them in lircrc, like:

include "~/.config/lircrc/mplayer"
include "~/.config/lircrc/mythtv"
include "~/.config/lircrc/vlc"

By default, lircd runs as user root. However, for increased stability and security, upstream recommends running it as a regular user. See Appendix 14 at this link.

is offered which does everything automatically.

Alternatively, users can complete the following steps to achieve the same result:

Create and provision a lirc user:

# groupadd -r lirc
# useradd -r -g lirc -d /var/lib/lirc -s /usr/bin/nologin -c "LIRC daemon user" lirc
# usermod -a -G lock,input lirc

Augment the package-providing service unit by creating a lircd Systemd#Drop-in files:

# systemctl edit lircd

[Service]
User=lirc
Group=lirc

CapabilityBoundingSet=CAP_SETEUID
MemoryDenyWriteExecute=true
NoNewPrivileges=true
PrivateTmp=true
ProtectHome=true
ProtectSystem=full

To allow devices to be accessible for the lirc group and to grant r/w access for the lirc group to USB devices using ACLs, copy the following udev rule into place:

# cp /usr/share/lirc/contrib/60-lirc.rules /etc/udev/rules.d/

To allow access to the lirc group to be able to create a PID file, create the following lircd tmpfile which will supersede the package provided one (which makes ownership only to root):

Reboot the system to verify expected function.

Run , point remote to the receiver and press some buttons. Received codes will be printed to stdout.

$ irw
000000037ff07bfe 00 One mceusb
000000037ff07bfd 00 Two mceusb
000000037ff07bfd 01 Two mceusb
000000037ff07bf2 00 Home mceusb
000000037ff07bf2 01 Home mceusb

If gives no output:

• Run mode2 or xmode2 to see if LIRC actually read something from IR sensor, if no - check the hardware
• If mode2 receives pulse data, check the configuration files in for errors

List registered remotes (configuration files):

$ irsend LIST "" ""
LG_6710CMAP01A

List available codes for the specific device:

$ irsend LIST LG_6710CMAP01A ""
0000000000007887 KEY_POWER
000000000000f807 KEY_MUTE
000000000000e817 KEY_VOLUMEUP
...

Choose discovered device and send command KEY_POWER:

$ irsend SEND_ONCE LG_6710CMAP01A KEY_POWER

Xorg detects some remotes, such as the Streamzap USB PC Remote, as a Human Interface Device (HID) which means some or all of the keys will show up as key strokes as if entered from the physical keyboard. This behavior will present problems if LIRC is to be used to manage the device.

To disable, create the following file and restart X:

Do not forget to alter the property according to one shown in from output of

$ cat /proc/bus/input/devices | grep -e IR

For example for

Blacklist the offending modules by creating /etc/modprobed.d/streamzap.conf to suppress this behavior. An example is provided for the Streamzap remote.

install ir_sharp_decoder /bin/false
install ir_xmp_decoder /bin/false
install ir_rc5_decoder /bin/false
install ir_nec_decoder /bin/false
install ir_sony_decoder /bin/false
install ir_mce_kbd_decoder /bin/false
install ir_jvc_decoder /bin/false
install ir_rc6_decoder /bin/false
install ir_sanyo_decoder /bin/false

Users not getting any output from may have the default configuration in incorrectly setup (or might have been overwritten by an update).

First, check if /dev/lirc0 is present:

$ mode2 --driver default --device /dev/lirc0

Watch the output while pressing buttons on the remote. If output is present, edit changing the driver and device appropriately.

If no output is presented, the task becomes locating the correct driver/device combination. First check what combination lirc detected by default. Run from the package. and check the output. It will look similar to this:

 Found /sys/class/rc/rc0/ (/dev/input/event5) with:
       Driver ite-cir, table rc-rc6-mce
       Supported protocols: unknown other lirc rc-5 jvc sony nec sanyo mce-kbd rc-6 sharp xmp
       Enabled protocols: lirc
       Extra capabilities: <access denied>

In this case, LIRC automatically detected as the IR device, which uses the driver. Check if this combination is working by running:

$ mode2 --driver devinput --device /dev/input/event5

Now try pressing buttons on the remote. If there is no output, try different driver and device combinations. Once a working combination has been identified, change driver and device in appropriately.

An example configuration for a MCE RC6 compatible receiver: