OWFS with i2c support on Raspberry Pi (English version)
This guide will help you to get OWFS working on Raspberry Pi's i2c GPIO port.
Goal
To get full OWFS support using the i2c bus the Raspberry Pi.
Software
- Raspian Wheezy
- OWFS (Latest tested version is 2.8p20)
Hardware
Prerequisites
This guide is written based on a clean install of Raspbian Wheezy (2012-10-28).
Modules
Make sure that the i2c-bus module is not included in the blacklist file.
sudo nano /etc/modprobe.d/raspi-blacklist.conf
Add "#" before
blacklist i2c-bcm2708
The row will look like this:
#blacklist i2c-bcm2708
Make sure that the i2c-dev module is included in /etc/modules
sudo nano /etc/modules
Add "i2c-dev" on it's own row in the file.
i2c-dev
Installation of OWFS
First you'll have to install som neccecary and usefull packages.
sudo apt-get update sudo apt-get install automake autoconf autotools-dev gcc-4.7 libtool libusb-dev libfuse-dev swig python2.6-dev tcl8.4-dev php5-dev i2c-tools
Answer Yes on any question during the install.
Download the latest version of OWFS (currently 2.8p20)
cd /usr/src sudo wget -O owfs-latest.tgz http://sourceforge.net/projects/owfs/files/latest/download
Unpack OWFS
sudo tar xzvf owfs-latest.tgz
Configure OWFS
cd owfs-2.8pXX sudo ./configure
If everything goes as planned you'll get a result like this:
Current configuration:
Deployment location: /opt/owfs
Compile-time options:
Caching is enabled
USB is DISABLED
I2C is enabled
HA7Net is enabled
W1 is enabled
Multithreading is enabled
Parallel port DS1410E is enabled
TAI8570 barometer is enabled
Thermocouple is enabled
Zeroconf/Bonjour is enabled
Debug-output is enabled
Profiling is DISABLED
Tracing memory allocation is DISABLED
1wire bus traffic reports is DISABLED
Module configuration:
owlib is enabled
owshell is enabled
owfs is enabled
owhttpd is enabled
owftpd is enabled
owserver is enabled
owexternal is enabled
ownet is enabled
ownetlib is enabled
owtap is enabled
owmon is enabled
owcapi is enabled
swig is enabled
owperl is enabled
owphp is DISABLED
owpython is DISABLED
owtcl is enabled
Compile OWFS, it will take approx 30 minutes
sudo make
Install OWFS, it will take a couple of minutes
sudo make install
Create a mountpoint for the 1wire folder.
sudo mkdir /mnt/1wire
To make it possible to access the 1wire devices without root privileges you'll have to modify the FUSE settings. Open the fuse configuration file:
sudo nano /etc/fuse.conf
Change
#user_allow_other
to
user_allow_other
Now you can start OWFS!
sudo /opt/owfs/bin/owfs --i2c=ALL:ALL --allow_other /mnt/1wire/
If you're using the USB adapter (DS9490R), just replace "--i2c=ALL:ALL" with "-u"
Make sure everything works as it should by checking the contents of the 1wire folder or by reading a sensor: (Change path according to your sensor id)
cat /mnt/1wire/10.F6877C010800/temperature
You should get the current temperature as result.
Make sure OWFS is started automatically at boot
Create the startup script in /etc/init.d/
cd /etc/init.d sudo nano start1wire.sh
Add the folowing to the file (remove the first space on each row):
#!/bin/bash ### BEGIN INIT INFO # Provides: start1wire # Required-Start: $local_fs $syslog # Required-Stop: $local_fs $syslog # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: Start OWFS at boot time # Description: Start OWFS at boot time ### END INIT INFO # Starts OWFS /opt/owfs/bin/owfs --i2c=ALL:ALL --allow_other /mnt/1wire
If you're using the USB adapter (DS9490R), just replace "--i2c=ALL:ALL" with "-u"
To make the script executable, run the following command:
sudo chmod +x start1wire.sh
Add the script to the default runlevel.
sudo update-rc.d start1wire.sh defaults
Congratulations, if you've made it this far you've installed OWFS with i2c support and made sure that it starts automatically when the Raspberry Pi boots.
