mode2 - Show pulse/space length or decoded input from infrared drivers.


   mode2 --driver <driver> [--device <device>] [other options]

   mode2 --raw --device <device> [other options]

   mode2 --driver <driver>  --list-devices


   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

   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.


   -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

   -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

   -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.


   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.


   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


   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).


       Used as fallback when there is no --loglevel option present. Syntax
       is the same as for --loglevel, see OPTIONS.


       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

       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.



   The documentation for lirc  is  maintained  as  html  pages.  They  are
   located under html/ in the documentation directory.


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