Section: User Commands (1)
Updated: Tue Jul 5 2016
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ir-ctl - a swiss-knife tool to handle raw IR and to set lirc options  


ir-ctl [OPTION]...
ir-ctl [OPTION]... --features
ir-ctl [OPTION]... --send [pulse and space file to send]
ir-ctl [OPTION]... --scancode [protocol and scancode to send]
ir-ctl [OPTION]... --receive [save to file]  


ir-ctl is a tool that allows one to list the features of a lirc device, set its options, receive raw IR, send raw IR or send complete IR scancodes.

Note: You need to have read or write permissions on the /dev/lirc device for options to work.  


-d, --device=DEV
lirc device to control, /dev/lirc0 by default
-f, --features
List the features of the lirc device.
-r, --receive=[FILE]
Receive IR and print to standard output if no file is specified, else save to the filename.
-s, --send=FILE
Send IR in text file. It must be in the format described below. If this option is specified multiple times, send all files in-order with a 125ms gap between them. The gap length can be modified with --gap.
Send the IR scancode in the protocol specified. The protocol must one of the protocols listed below, followed by a colon and the scancode number. If this option is specified multiple times, send all scancodes in-order with a 125ms gap between them. The gap length can be modified with --gap.
-1, --oneshot
When receiving, stop receiving after the first message, i.e. after a space or timeout of more than 19ms is received.
-w, --wideband
Use the wideband receiver if available on the hardware. This is also known as learning mode. The measurements should be more precise and any carrier frequency should be accepted.
-n, --no-wideband
Switches back to the normal, narrowband receiver if the wideband receiver was enabled.
-R, --carrier-range=RANGE
Set the accepted carrier range for the narrowband receiver. It should be specified in the form 30000-50000.
-m, --measure-carrier
If the hardware supports it, report what the carrier frequency is on receiving. You will get the keyword carrier followed by the frequency. This might use the wideband receiver although this is hardware specific.
-M, --no-measure-carrier
Disable reporting of the carrier frequency. This should make it possible to use the narrowband receiver. This is the default.
-t, --timeout=TIMEOUT
Set the length of a space at which the receiver goes idle, specified in microseconds.
-c, --carrier=CARRIER
Sets the send carrier frequency.
-D, --duty-cycle=DUTY
Set the duty cycle for sending in percent if the hardware support it.
-e, --emitters=EMITTERS
Comma separated list of emitters to use for sending. The first emitter is number 1. Some devices only support enabling one emitter (the winbond-cir driver).
-g, --gap=GAP
Set the gap between scancodes or the gap between files when multiple files are specified on the command line. The default is 125000 microseconds.
-?, --help
Prints the help message
Give a short usage message
-v, --verbose
Verbose output; this prints the IR before sending.
-V, --version
print the v4l2-utils version


Format of pulse and space file

When sending IR, the format of the file should be as follows. A comment start with #. The carrier frequency can be specified as:

       carrier 38000

The file should contain alternating lines with pulse and space, followed by length in microseconds. The following is a rc-5 encoded message:

       carrier 36000

       pulse 940

       space 860

       pulse 1790

       space 1750

       pulse 880

       space 880

       pulse 900

       space 890

       pulse 870

       space 900

       pulse 1750

       space 900

       pulse 890

       space 910

       pulse 840

       space 920

       pulse 870

       space 920

       pulse 840

       space 920

       pulse 870

       space 1810

       pulse 840

Rather than specifying the raw IR, you can also specify the scancode and protocol you want to send. This will also automatically set the correct carrier. The above can be written as:

       scancode rc5:0x1e01

If multiple scancodes are specified in a file, a gap is inserted between scancodes if there is no space between then (see --gap). One file can only have one carrier frequency, so this might cause problems if different protocols are specified in one file if they use different carrier frequencies.

Note that there are device-specific limits of how much IR can be sent at a time. This can be both the length of the IR and the number of different lengths of space and pulse.


Supported Protocols

A scancode with protocol can be specified on the command line or in the pulse and space file. The following protocols are supported: rc5, rc5x_20, rc5_sz, jvc, sony12, sony15, sony20, nec, necx, nec32, sanyo, rc6_0, rc6_6a_20, rc6_6a_24, rc6_6a_32, rc6_mce, sharp. If the scancode starts with 0x it will be interpreted as a hexadecimal number, and if it starts with 0 it will be interpreted as an octal number.


Wideband and narrowband receiver

Most IR receivers have a narrowband and wideband receiver. The narrowband receiver can receive over longer distances (usually around 10 metres without interference) and is limited to certain carrier frequencies.

The wideband receiver is for higher precision measurements and when the carrier frequency is unknown; however it only works over very short distances (about 5 centimetres). This is also known as learning mode.

For most drivers, enabling carrier reports using -m also enables the wideband receiver.  

Global state

All the options which can be set for lirc devices are maintained until the device is powered down or a new option is set.  


On success, it returns 0. Otherwise, it will return the error code.  


To list all capabilities of /dev/lirc2:
       ir-ctl -f -d /dev/lirc2

To show the IR of the first button press on a remote in learning mode:
       ir-ctl -r -m -w

Note that ir-ctl -rmw would receive to a file called mw.

To restore the normal (longer distance) receiver:
       ir-ctl -n -M

To send the pulse and space file play on emitter 3:
       ir-ctl -e 3 --send=play

To send the rc-5 hauppauge '1' scancode:
       ir-ctl -S rc5:0x1e01


Report bugs to Linux Media Mailing List <>  


Copyright (c) 2016 by Sean Young.

License GPLv2: GNU GPL version 2 <>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.



Format of pulse and space file
Supported Protocols
Wideband and narrowband receiver
Global state