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
- Noobs 1.3.12 (2015-02-02) / Raspian Wheezy
- OWFS (Latest tested version is 3.0p0)
Hardware
Prerequisites
This guide is written based on a clean install of Raspbian Wheezy installed via Noobs 1.3.12 (2015-02-02).
Modules
Add i2c-bcm2708 and i2c-dev in /etc/modules
sudo nano /etc/modules
Add them on separate lines in the file.
i2c-bcm2708 i2c-dev
Open /boot/configt.txt
sudo nano /boot/config.txt
Add the following lines at the bottom
dtparam=i2c1=on dtparam=i2c_arm=on
Reboot:
sudo reboot
Verify that the i2c to 1wire module is found
Run
sudo i2cdetect -y 1
Which should give an output like this:
0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- 1b -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- --
If you see 1b, the i2c to 1wire module is found.
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-1.0-0-dev libfuse-dev swig python2.7-dev tcl8.5-dev php5-dev i2c-tools
Answer Yes on any question during the install.
Download the latest version of OWFS (currently 3.0p0)
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-3.0p0 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 on A/B/A+/B+ and approx 5 minutes on Pi 2 A/B/A+/B+
sudo make
Pi 2 (-j 4 makes sure all four cores is used)
sudo make -j 4
Install OWFS, it will take a minute or two
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.