mode2(1)
NAME
mode2 - Show pulse/space length or decoded input from infrared drivers.
SYNOPSIS
mode2 --driver <driver> [--device <device>] [other options] mode2 --raw --device <device> [other options] mode2 --driver <driver> --list-devices
DESCRIPTION
The main purpose of this program is to check operation of your home- brew LIRC receiver hardware and to see the IR waveform of the remote controller without an expensive oscilloscope. Very useful for debugging also in situations you just need to verify configuration. mode2 will simply print pulse and space lengths to stdout for drivers supporting LIRC_MODE_MODE2. For drivers supporting LIRC_MODE_LIRCCODE such as TV-cards and the irman driver writes the decoded, integer values. When given the correct driver mode2 should always work. Without a driver, the --raw option should always work for /dev/lirc* devices. At the time of writing, usb devices also works in most cases. However, since it is tricky to get the path to the usb device, such ones are normally best accessed using a driver. Not all drivers requires a device.
OPTIONS
-d --device=device
Read from given device.
-H --driver=driver
Use given driver.
-m --mode
Write pulse/space data as raw config files. Does not affect
LIRCCODE drivers.
-s --scope=time
Enable 'scope like display with time us per char. Does not
affect lirccode drivers.
-k --keep-root
Don't drop root privileges after opening device. See RUNNING AS
ROOT.
-l --list-devices
List all available devices for given driver. Requires support
not present in all drivers.
-g --gap=time
Treat spaces longer than time as the gap. Time is in
microseconds.
-r --raw
Access device directly. This is primarely intended to be used
with kernel rc drivers i .e., when accessing /dev/lirc* devices.
Using other devices might work, but is in general undefined.
-A --driver-options=key:value[|key:value...]
Set driver-specific option named key to given value.
-U --plugindir=directory
Load drivers from directory. See DRIVER LOADING.
-O, --options-file <path>
File containing default values for all options. A relative path
is interpreted from current directory. See [FILES] below.
-D --loglevel=level
Determine the amount of logging information. [level] can be a
symbolic syslog level: 'error','warning, 'info', 'notice' or
'debug'. lirc also defines three additional levels 'trace',
'trace1' and 'trace2' which gives even more messages ('trace2'
bringing the most). However, in the log these messages are
marked as 'debug'. The level can also be an integer in the
range 3 (almost no messages) to 10.
-h --help
Display usage summary.
-v --version
Display version.
RUNNING AS ROOT
In many cases mode2 needs to run as root to access devices not
available to regular users. On the other hand, running as root creates
problems such as log files owned by root, security concerns etc.
In order to cope with this, mode2 by default drops root privileges
after opening the input device. This support is based on that root
permissions are accquired using sudo(1) e. g., using
$ sudo mode2 --raw /dev/lirc0
If not using sudo, the same behaviour could be accomplished using the
SUDO_USER environment variable e. g.,
# SUDO_USER=$LOGNAME mode2 --raw /dev/lirc0
The --keep-root option will make mode2 to keep root privileges for the
complete run.
EXAMPLES
Invoked with a MODE2 type driver with mode2 prints space/mark timings:
al@snorken $ ./mode2 --driver default --device /dev/lirc0
Using driver default on device /dev/lirc0
Trying device: /dev/lirc0
Using device: /dev/lirc0
pulse 2750
space 800
pulse 500
space 350
pulse 550
space 350
pulse 550
...
Invoked with a LIRCCODE type driver mode2 prints decoded values:
$ ./mode2 --driver atilibusb
Using driver atilibusb on device /dev/lirc0
Trying device: /dev/bus/usb/001/007
Using device: /dev/bus/usb/001/007
code: 0x14709b0000
code: 0x14709b0000
code: 0x14709b0000
code: 0x14709b0000
code: 0x14709b0000
...
DRIVER LOADING
Drivers are loaded dynamically. The search path used for this is
determined by (falling priority):
- The --plugindir option.
- The 'plugindir' entry in the [lircd] section of the
lirc_options.conf file.
- The environment variable LIRC_PLUGINDIR.
- A hardcoded default (/usr/lib/x86_64-linux-gnu/lirc/plugins).
ENVIRONMENT
LIRC_LOGLEVEL
Used as fallback when there is no --loglevel option present. Syntax
is the same as for --loglevel, see OPTIONS.
FILES
/etc/lirc/lirc_options.conf
The options file holding default values for command line options in
the [mode2] section. For some values including debug, plugindir,
driver and device mode2 falls back to the [lircd] section if not
found in [mode2].
The location of this file can be changed using the -O/--options-
file command-line option or using the environment variable
LIRC_OPTIONS_PATH.
~/.cache/mode2.log
Debug log. Setting the XDG_CACHE_HOME environment variable
relocates this file to $XDG_CACHE_HOME/mode2.log. The amount of
logging respects the LIRC_LOGLEVEL environment variable, defaulting
to the debug value in lirc_options.conf.
SEE ALSO
xmode2(1) lirc(4) The documentation for lirc is maintained as html pages. They are located under html/ in the documentation directory.
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