irattach — binds the Linux-IrDA stack to a IrDA port
irattach [<dev>] [-s] [-d dongle] [-v] [-h]
irattach binds the Linux-IrDA stack to an IrDA port. It configures the
low level of the Linux-IrDA stack in the kernel. This step is usually
necessary before you (or applications) can use the higher layer of the
The irattach command loads the necessary Linux-IrDA driver, which con-
figures the IrDA hardware, and configures the IrDA stack to operate on
the new IrDA port. Multiple IrDA ports can be activated through multi-
ple irattach commands.
irattach by default uses the irtty driver which connects to the Linux
TTY subsystem and use the standard Linux serial driver. This works well
for most machines and configurations, but limits the baud rate to
115200bps (IrDA SIR mode). The mode of operation will work with most
FIR hardware (as found in laptops - they provide serial emulation) and
most serial dongles (provided the proper dongle type is specified),
making it a safe choice. However, USB dongles and a few FIR hardware
don’t support serial emulation and can’t be used with the irtty driver.
irattach can also use one of the Linux FIR drivers (including USB don-
gle drivers) instead of the irtty driver. Most FIR drivers require
proper configuration of module parameters (this is documented below).
FIR drivers allow you to use higher baud rates (generally up to 4Mbps).
In general, Linux FIR support is not as stable and mature, due to lack
of time and documentation.
irattach must be run as root or installed setuid root, as it requires
root privileges. If you have compiled the IrDA stack as modules (recom-
mended), then you will need to edit the /etc/modules.conf file. See
the Infrared-HOWTO for details.
<dev> : this is the name of a TTY, an IrDA interface or IrDA driver.
irattach decides to use the irtty driver or one of the FIR drivers
based on this argument.
· TTY name : this is the serial port to be configured using the
irtty driver, such as /dev/ttyS0. irattach will use the irtty
driver, so only SIR will be available. You need to check your
serial configuration or BIOS to know which serial port is the
IrDA port that need to be passed to irattach.
· interface name : this is the device name of an IrDA interface,
such as irda0. irattach will use one of the FIR drivers (includ-
ing USB dongle drivers). The selected FIR driver must be loaded
prior to the call to irattach, or the proper alias for the device
name must be set in /etc/modules.conf.
· module name : this is the name of an FIR driver module, such as
nsc-ircc (see list below). All new IrDA interfaces created after
loading the module will be configured, so this won’t work if the
module is already loaded. This feature is still experimental.
-s : starts discovery of remote IrDA devices (note that the form "-s 1"
is no longer supported)
-v : shows version information (this happens, when no option is given,
-h : shows help information.
-d dongle : attaches an additional dongle driver to the IrDA port.
You need a dongle driver if you have an infrared device that connects
to your computer’s serial port (normal 9-pin serial port connector).
These devices are called dongles, and can currently be used by any SIR
driver (IrTTY or irport). This option is not compatible with FIR
drivers, and only works with the irtty and irport drivers.
The currently known (serial) dongles are:
· esi Extended Systems JetEye PC ESI-9680
· tekram Tekram IrMate IR-210B dongle
· actisys ACTiSYS IR-220L dongle
· actisys+ ACTiSYS IR-220L+ dongle
· girbil Greenwich GIrBIL dongle
· litelink Parallax LiteLink dongle & Extended Systems JetEye PC
· airport N.N.
· old_belkin Belkin (old) SmartBeam dongle or any dongle only capa-
ble of 9600 bauds
· ep7211 IR port driver for the Cirrus Logic EP7211 processor
· mcp2120 Dongles based on the MCP2120 (Microchip)
· act200l ACTiSYS Ir-200L dongles
· ma600 Mobile Action ma600 dongles
FIR DRIVER MODULES
If you are one of the lucky people which have a FIR chipset or USB don-
gle that is supported by one of the Linux-IrDA drivers, you can use
irattach with the interface name of the IrDA port to configure. You
will need to configure /etc/conf.modules appropriately, with at least
an alias of irda0 to the driver name, or load the driver manually
You don’t strictly need to use irattach with FIR drivers, you can use
modprobe to load the driver, ifconfig to bring up the interface and set
the various sysctl by hand, but irattach offer a convenient way to do
Of course, you need to know which FIR driver applies to your hardware.
You may use findchip to get information about the FIR chip. If this
doesn’t help, the Infrared-HOWTO shows other means to retrieve these
Also, you often need to configure the Linux-serial driver to ignore the
IrDA port, otherwise both drivers will conflict. This can usually be
done with setserial /dev/ttySx uart none.
The currently known FIR drivers are:
· ali-ircc ALi FIR Controller Driver for ALi M5123 (options: io,
irq, dma). This driver supports SIR, MIR and FIR (4Mbps) speeds.
This chipset is used by e.g.:
The ALi M5123 FIR Controller is embedded in ALi M1543C,
M1535, M1535D, M1535+, M1535D South Bridge.
· irda-usb IrDA-USB device driver, for USB devices/dongles that
comply with the official IrDA-USB class specification. Note: USB
2.0 is not yet tested. (options: qos_mtt_bits int, description
"Minimum Turn Time"). This is used, for e.g.:
KC Technology KC-180
Extended Systems XTNDAccess ESI-9685
Note that there is another USB driver for those devices
called ir-usb which is NOT compatible with the IrDA stack and
conflict with irda-usb. Because it always loads first, you
have to remove ir-usb completely.
Devices based on the SigmaTel chip are not not compliant with
the IrDA-USB class specification and therfore not supported
by this driver.
· nsc-ircc NSC IrDA device driver (options: io, irq, dma, don-
gle_id, qos_mtt_bits). This chipset is used by e.g.:
IBM ThinkPad dongle_id=0x09
HP OmniBook 6000 dongle_id=0x08
· sa1100_ir Infrared driver for devices based on the StrongARM
SA1100 embedded microprocessor (options: power_level, tx_lpm).
This driver may support FIR on devices that can do it. This
chipset is used by e.g.:
Samsung YOPY, COMPAQ iPAQ, SHARP Zaurus SL5000/5500
· smc-ircc SMC IrCC controller driver (options: ircc_dma,
ircc_irq). This chipset is used by e.g.:
Fujitsu-Siemens Lifebook 635t Sony PCG-505TX
· w83977af_ir Winbond W83977AF IrDA device driver (options: io,
irq, qos_mtt_bits). This chipset is used by e.g.:
· toshoboe Toshiba OBOE IrDA device driver, supports Toshiba Type-O
IR chipset. (options: max_baud). This chipset is used by e.g.:
Toshiba Libretto 100CT., and many more old Toshiba laptops.
· donauboe is a new version of toshoboe and has better FIR support
and compability with the Donauoboe chip http://libxg.free.fr/lib-
irda.html (options: ..). This chipset is used by e.g.:
Toshiba Libretto 100CT., Tecra 8100, Portege 7020 and many
more Toshiba laptops.
· vlsi_ir VLSI 82C147 SIR/MIR/FIR device driver This chipset is
used by e.g.:
HP Omnibook 800
· clksrc int, description "clock input source selection"
· ringsize int array (min = 1, max = 2), description "tx,
rx ring descriptor size"
· sirpulse int, description "sir pulse width tuning"
· mtt_bits int, description "IrLAP bitfield representing
Attach the IrDA stack to the second serial port (integrated IrDA port
using serial emulation) and start discovery:
· irattach /dev/ttyS1 -s
Attach the IrDA stack to the first serial port where you have an exter-
nal ACTiSYS serial dongle and start discovery:
· irattach /dev/ttyS0 -d actisys+ -s
Attach the IrDA stack to the first IrDA-USB dongle and start discovery:
· modprobe irda-usb ; irattach irda0 -s
Attach the IrDA stack to the NSC FIR (4Mbps) device driver on a
· modprobe nsc-ircc dongle_id=0x9 ; irattach irda0 -s.
Attach the IrDA stack to the NSC FIR (4Mbps) device driver on a
· irattach irda0 -s.
This assume that you have added the following entries to
options nsc-ircc dongle_id=0x09
alias irda0 nsc-ircc
The following hints are a very short introduction into the configura-
tion of Linux/IrDA. If this doesn’t help read the Linux/IrDA-Tutorial
and/or the Infrared-HOWTO . Before configuring Linux/IrDA make sure
whether you want to configure SIR or FIR. It’s recommended to try SIR
first, unless your device is not compatible with SIR (for example USB
To get the SIR "serial" device have a look into the BIOS. Then run
dmesg | grep tty to get a survey of tty devices supported by your
machine. Now try to choose the one, which is probably the IrDA device
and use irattach /dev/ttySx -s.
If you don’t succeed with SIR (which seems a rare case) you may try
FIR. First look up the BIOS. Then run findchip to get information about
the IrDA controller chip. Use setserial /dev/ttySx uart none to avoid
conflicts with the serial driver. Note: don’t use setserial if you
configure SIR. Now you may use irattach.
Finally irdadump should show at least your computer itself. If it
doesn’t start at the beginning.
This man page deal only with the low level of the IrDA stack (IrDA
ports and IrDA drivers). After this step is done, you usually need to
setup your favorite application to access the high level IrDA stack
(via IrCOMM, IrLPT, IrNET, IrLAN or IrSOCK), which is documented else-
This man page doesn’t document the usage of the irport driver. The
irport driver support the same hardware as the irtty driver, but is
configured like a FIR driver.
This section currently contains the raw error messages from source code
"irattach: tty: set_disc(%d): %s"
"Failed to open %s: %m"
"Couldn’t get device fd flags: %m"
"Couldn’t set device to non-blocking mode: %m"
irattach(8), irdaping(8), irdadump(8), findchip(8), irpsion5(8), mod-
Linux/IrDA Project http://irda.sourceforge.net -*- Linux/IrDA-Tutorial
Infrared-HOWTO http://tuxmobil.org/howtos.html -*- Infrared-Hardware-
This manual page is written by Werner Heuser firstname.lastname@example.org. It is
based on the READMEs from irda-utils by the Linux/IrDA Project and the
Linux/IrDA-Tutorial. It was subsequently updated and modified by Jean
Copyright (c) 2001 Werner Heuser Copyright (c) 2002 Jean Tourrilhes
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License (GFDL), Version
1.1 or any later version published by the Free Software Foundation;
with no Invariant Sections, no Front-Cover Texts and no Back-Cover
Man(1) output converted with