Section: Commands (1)
Updated: Last change: Jan 2017
mode2 - Show kernel output available for LIRC drivers
mode2 --driver <driver> [--device <device>] [other options]
mode2 --raw --device <device> [other options]
mode2 --driver <driver> --list-devices
The original purpose of this program has been to check operation of home-brew LIRC receiver hardware and to see the IR waveform of the remote controller without an expensive oscilloscope. Over time, mode2 has evolved to a generic tool to check what kind of output the kernel makes available for lirc.
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.
From version 0.9.4, mode2 can also list the devices available for a given driver. This requires enumeration support which is available in most but not all drivers.
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.
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 ... Invoked using mode2 --list-devices for the devinput driver with a single X10 RF usb device plugged in: $ ./mode2 --list-devices --driver devinput /dev/input/event12 [0bc7:0006] X10 WTI RF receiver vers: 1.10 serial: ? /dev/input/by-id/usb-X10_WTI_RF_receiver-event-if00 -> ../event12 /dev/input/by-path/pci-0000:0b:00.0-usb-0:1:1.0-event -> ../event12
Drivers are loaded dynamically. The search path used for this is determined by (falling priority):
The documentation for lirc is maintained as html pages. They are located under html/ in the documentation directory.
This document was created by
using the manual pages.
Time: 20:22:15 GMT, June 09, 2017