Howto setup an infrared-connection with Belkin F5U235 and Linux

On this page you will a find a short guide on how to set up this USB infrared adapter with Linux.
Please note: the page was written in 2005, so many things I had to do the hard way back then can now be skipped or will work automatically (e.g. the driver is included in the vanilla kernel now, so Step 1 can be skipped altogether).

All comments, suggestions etc. are welcome. Please contact me at

Setting up the Infrared USB Dongle

I assume you have the USB-subsystem up and running.

Step 1: Kernel-Config

The Belkin F5U235 works with a vanilla-kernel at least since kernel 2.6.12 (what I am using right now).

You need the stir4200.c module, ver. 0.4 works for the SigmaTel STIr4200 chip.
If you are using an older version of the kernel where the module is not included you can download a patch from

Compile (recommended: as a module)

The necessary Parameters in the kernel-.config-file are

Step 2: Install Necessary Software

Install the following software packages:

for debian users:
install the necessary packages:
apt-get install irda-utils

for non-debian users:
Go to
Download and compile/install irda-utils.

Step 3: Configure USB-Subsystem

The loading of the module works out-of-the-box.
You only have to bring the interface up
ifconfig irda0 up
and start detection of other infra-red devices
echo -n "1" > /proc/sys/net/irda/discovery

In former versions of irda-utils for this purpose the program irattach had to be used.

Step 4: Infrared Setup

You have to enter the appropriate parameters when installing the irda-utils package.
This is the contents of the file /etc/default/irda-utils (this is Debian, the location of such a config-file depends on your distribution).


Now you can connect to another device via infrared and the device /dev/ircomm0. Fire up any terminal program like minicom to test and play.

SieFS doesn't work with this IR-adapter (altough it does on the same machine with my serial IR adapter). I can mount the phone but it cannot display any directory contents (after some time I get an Input/output error). Obexftp works.

I cannot tell if FIR-mode works, too, since I don't have a FIR-device to test it. If you can try FIR please send me an e-mail whether it works.

Have fun!

Some interesting links:

Infrared Devices at

Written 2005-06-22 - last update 2006-08-19