Section: User Commands (1)
Updated: Tue Jul 5 2016
ir-ctl - a swiss-knife tool to handle raw IR and to set lirc options
[pulse and space file to send
[protocol and scancode to send
[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.
- -S, --scancode=PROTOCOL:SCANCODE
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
- -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
- -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
- -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:
The file should contain alternating lines with pulse and space, followed
by length in microseconds. The following is a rc-5 encoded message:
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:
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
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.
A scancode with protocol can be specified on the command line or in the
pulse and space file. The following protocols are supported:
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
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.
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 <firstname.lastname@example.org>
Copyright (c) 2016 by Sean Young.
License GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.