1-Wire Wireless Router

Synopsis:

The Hack

• Jim Buzbee very cleverly adds a mini distribution to the router. See his page for full explanation. This is a simple script that adds user tools, like busybox, telnet, etc to make the router accessible. The nice part is that the router is not harmed, a reset restores it to pristine state.
• OWFS is 1-wire filesystem for linux that allows 1-wire access for linux. It is quite light-weight, and will run from the ram disk.
• Chrstian Magnusson is modifying OWFS for the WRT54G, based on his experience getting owfs to run on coldfire processors. This is quite a feat considering that he is changing glibc to uClibc, processor architecture, memory and mutex handling, and filesystem organization.

Hardware

• Serial ports

  There are several discussion on the web for accessing the hardware of the WRT54G and adding serial ports. Rod Whitby
  
  has a beautifully illustrated and annotated discussion. See also http://jdc.parodius.com/wrt54g/serial.html
  Adding a serial adapter requires a serial to 1-wire adapter. See my list.

• DS2480B

  At least in theory, it should be possible to add the DS2480B directly to the board. Here is a rough schematic:
  
  
  
  The idea behind this circuit is taking the serial outputs from the circuit board header (WRT54G v2 and WRT54GS, not earlier versions). The 3.3V is stepped up by the MAX883, and DS2480B negotiates with the 1-wire bus, the capacitors are for signal conditioning (from the MAX883 datasheet) and the diodes (you can use the DS9503) protect the circuit from attempts to drive the data line too low. Additional note: Rev4 of the circuit uses shottky diodes and a 7805 voltage regulator. Power source is from the power to the box, not the 3.3V on the serial header.
  

  On Wed, Jun 17, 2009 at 6:59 AM, Plich Konrad wrote:
  
  > Please note that schematic http://owfs.sourceforge.net/rev4.png linked on
  > the page http://owfs.sourceforge.net/WRT54G.html  has mistake: 1-wire bus
  > schould be connected to PIN2 of DS24080B and not to PIN3 - this one is NC.
  >
  > Second mistake is connected with PIN 6 - acording to DS2480 data sheet it
  > should be conected to +5v for 3.3V serial operation.
  >
  > Please correct it - in this form the picture can spoil a lot of time for
  > careless people (like it did for me :-)
  

• Circuit Improvements

  David Lissiuk of Springbok writes:
  I'd suggest the use of Shottky diodes for the line protection instead of IN4004 (faster response). Putting optocouplers and DC to DC in the circuit would protect the Linksys from anything that happened to the 1-wire side. (Maybe as an optional components?) The addition of switchable line filter on the 1-wire side of the DS2480 would be appropriate also to remove the need in some situations. Need to look closer at the Linksys for other suggestions.
  

• Available as Kit or Assembled

  
  

  David Lissiuk has announced availability of a working circuit for modifyiong the Linksys router. He includes better protection, optional sensors, and a second serial port.
  



• Hardware docs

  • Linksys WRT54G User Guide
    
  • Linksys circuit board serial header:
    The pinout of JP1 on the Linksys PCB is as follows:
    
    Pin  1: 3.3V        Pin  2: 3.3V
    Pin  3: Tx (ttyS1)  Pin  4: Tx (ttyS0)
    Pin  5: Rx (ttyS1)  Pin  6: Rx (ttyS0)
    Pin  7: NC          Pin  8: NC
    Pin  9: GND         Pin 10: GND
  • DS2480B
    
     
    
  • DS9097U
    
    
    

Software
(works for both DS2480B direct circuit and serial port with adapter)

If you just want to try owfs by uploading the binaries to RAM (without upgrading your firmware) follow the instructions below:

1. Download and unpack owfs_wrt54g-*.tar.gz from the download area.
2. If you want to upload and start owhttpd only, then you could start the script:
   

   host> ./upload-owhttpd [host]
   

3. Try http://192.168.1.1:3001/ after the script has finished. You should now see the 1-wire devices connected to your router.
4. If you want to upload all owfs files, including fuse-module, owfs, owhttpd and some start-scripts, then you have to install wrt54g-0.51.tar.gz from Buzbee's website first. (see above)
   Download it from http://www.batbox.org/wrt54g-linux.html, unpack and install it. (and eventually modify wrt54g.sh for local conditions)
5. You should now be able to install the owfs-files with the script called
   

   host> ./upload-all [host]
   

6. You can now try to start everything (owserver + owfs + owhttpd).
   

   host> telnet 192.168.1.1
   / # kill-owfs    (stop old running processes)
   / # run-owserver
   Starting owserver (/dev/tts/1)
   Starting owhttpd (owserver)
   Starting owfs (owserver)
   Using /var/bin/fuse.o
   / # ls /var/1wire/
   1F.CCF201000000  settings         structure        uncached
   alarm            statistics       system
   

   If you want to create graphs on all temperature sensors, then start temploggerd.
   

   / # run-temploggerd
   Starting temploggerd
   / # 
   

   Visit http://192.168.1.1:8000/temploggerd/ after the script has finished. You should now see a list of all 1-wire devices, and the links will display graphs of all temperature sensors.
   If you want to change the generated web-pages, then you could edit the template files before starting temploggerd. Some of the template-files are:

   index.html.templ all_temperature.cgi.templ sensor_temperature.cgi.templ all.cgi.templ

Firmware with OWFS based on ewrt-0.3
(works for both DS2480B direct circuit and serial port with adapter)

NOTE: Don't try to use it unless you know what you are doing! LOADING AN UNOFFICIAL FIRMWARE WILL VOID YOUR WARRANTY

1. Download and unpack owfs_wrt54g-firmware-*.tar.gz from the download area.
2. Set your router configuration BOOT_WAIT=1. Don't upgrade your firmware until this is done!!! The OpenWRT project has a good page which helps you set the BOOT_WAIT configuration.
3. Upgrade your WRT54G firmware with the file "code.bin"
4. After your router has rebooted, login with ssh and start owfs.
   

   host> ssh root@192.168.1.1
   / # /usr/bin/rc.start.example
   Starting owserver (/dev/tts/1)
   Starting owhttpd (owserver)
   Starting owfs (owserver)
   Using /var/bin/fuse.o
   Starting temploggerd
   / # ls /var/1wire/
   1F.CCF201000000  settings         structure        uncached
   alarm            statistics       system
   

   Visit http://192.168.1.1:8000/temploggerd/ after the script has finished. You should now see a list of all 1-wire devices, and the links will display graphs of all temperature sensors.
   If you want to change the generated web-pages, then you could edit the template files before starting temploggerd. Some of the template-files are:

   index.html.templ all_temperature.cgi.templ sensor_temperature.cgi.templ all.cgi.templ

   
   
   If everything seems to work, then copy the startup-script to /opt/rc.start if you want it to start automatically when rebooted.
   

   / # cp /usr/bin/rc.start.example /opt/rc.start
   

Packages with OWFS to OpenWRT distribution

NOTE: These packages require you to have OpenWRT installed on your router.

1. I can't recommend OpenWRT to users without any experience of Linux, shells-script experience. There are NO web-interface to configure all network settings, so you should have some knowledge and read the documentation, FAQ and examples at OpenWrtDocs, OpenWrtFaq and the forums.
2. Set your router configuration BOOT_WAIT=1. Don't upgrade your firmware until this is done!!! The OpenWRT project has a good page which helps you set the BOOT_WAIT configuration.
3. Download and install OpenWRT.
   I installed RC5-version of openwrt-wrt54gs-jffs2.bin as a firmware on my WRT54GS router. (and openwrt-wrt54g-jffs2.bin if you have a WRT54G router.)
4. Make sure to read the OpenWRT documentation on http://wiki.openwrt.org/OpenWrtDocs before you flash the new firmware. Go to the "Administration->Firmware" tab and select the path where you have the .bin file. Upgrading the firmware could take up to 5 minutes. DON'T reboot or power-off the router during this procedure!
5. First time OpenWRT is booting (after the firmware-upgrade), it will setup and prepare the jffs2 partition. This could take 1-2 minutes. Be patient and wait....
6. When filesystems are created, you have to reboot your router once more to mount the filesystems in read/write mode. This reboot is neccesary to do since you are going to install new packages. You should be able to login with telnet and reboot it manually when it's ready.
   

   host> telnet 192.168.1.1
   root@OpenWrt:/# reboot
   

7. Login to your router add my repository http://owfs.sourceforge.net/openwrt/packages/ to your /etc/ipkg.conf
   

   host> telnet 192.168.1.1
   root@OpenWrt:/# echo "src owfs http://owfs.sourceforge.net/openwrt/packages" >> /etc/ipkg.conf
   

8. Update the ipkg repository and install the packages
   

   ipkg update
   ipkg install ntpclient
   ipkg install owfs
   ipkg install temploggerd
   

   (Note: libpthread, kmod-fuse, libfuse, fuse-utils, librrd1, rrdtool1, rrdcgi1 will also be installed due to dependencies)
   (Note: ntpclient or rdate should set the date if the router reboots. If not, the graphs won't show correct date)
   
9. Try starting owfs and temploggerd manually (after setting date):

   /etc/init.d/S60ntpclient
   run-owfs
   run-temploggerd
   

   (Default settings for the scripts could be changed in /etc/default/*)
10. Visit http://192.168.1.1/temploggerd/ after the scripts has finished and the rrd-file is created (could take 30 seconds). You should now see a list of all 1-wire devices, and the links will display graphs of all temperature sensors.
    If you want to change the generated web-pages, then you could edit the template files in /usr/share/temploggerd/templates/ before starting temploggerd. Some of the template-files are:

    index.html.templ all_temperature.cgi.templ sensor_temperature.cgi.templ all.cgi.templ

11. To upgrade all installed packages to the latest version, just run the commands:
    

    ipkg update
    ipkg upgrade
    

12. Since there are startup-scripts for all applications, you should be able to reboot your router and have owfs and temploggerd automatically restarted.
13. All files generated from temploggerd are saved in /var/lib/temploggerd/ as default. Those files are lost if router reboots since it's located in the ramfs partition. Therefor I added the config-parameters "backup_dir" and "backup_freq" in /etc/temploggerd.conf which tell temploggerd to copy all files from /var/lib/temploggerd/ to /opt/backup (in flash-disk) once per hour for example. This method will increase the lifetime of the flash-memory and give you the possibility to save the rrd-files if you reboot the router. You could of course make a cronjob to copy the files from /var/lib/temploggerd/ to /opt/backup/temploggerd/ for example, if you feel more comfortable with that. Remember that a startup-script should then copy the backup files to /var/lib/temploggerd/ before starting temploggerd.