Using the TonidoPlug² as a Datalogger for Photovoltaic Panels

I managed to setup my TonidoPlug² (TP2) as a data-logger that automatically uploads live statistics of my solar panels to pvoutput.org. This post details the steps I followed to run sma-bluetooth on the TP2 .

After ssh'ing to your TP2, prepare a build environment on the plug pc:

• follow the steps in: http://www.tonido.com/communitywiki/doku.php?id=advanceduses:setupbuildenvironment
• step 4 & 5 are slightly outdated:
  • (4a) I had to install the deb-multimedia-keyring package first:

    apt-get install deb-multimedia-keyring 
    

  • (4b) the url for wget is diffent:

    wget http://www.debian-multimedia.org/pool/main/d/debian-multimedia-keyring/debian-multimedia-keyring_2010.12.26-3_all.deb 
    

  • (5) dpkg -i debian-multimedia-keyring_2010.12.26-3_all.deb

After that you can follow the steps I detailed in my previous post: http://michael-peeters.blogspot.com/2012/04/sb-inverter-bluetooth-connection-on.html. Summarized:

• compile sma-bluetooth:

  wget http://sma-bluetooth.googlecode.com/files/sma-bluetooth-0.17b.tar.gz 
  tar -xzf sma-bluetooth-0.17b.tar.gz 
  cd sma-bluetooth-0.17 
  sudo apt-get install mysql-server mysql-client  libmysqlclient-dev 
    # (don't forget to enter a non-blank password for mysql!) 
   
   gcc -c smatool.c 
   gcc smatool.o -L/usr/lib -lmysqlclient -lbluetooth -lcurl -lm -o smatool 
  

• edit the configuration. This can be tricky! Check the details first.

  # nano ./smatool.conf 
  

• install the mysql tables:

  ./smatool --INSTALL 
  

• run / debug errors:

  ./smatool -d -v 
  

Once smatool runs OK from the command-line, you can consider scheduling the run in cron.

• create a smatool.cron file in your home-directory. Contents:
  

  # /etc/cron.d/smatool: crontab entries for smatool (monitoring of Sunnyboy Grid Interactive Inverter) 
   
  SHELL=/bin/sh 
  PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/home/smatool/bin 
   
  # The following line runs the smatool every 15 minutes between 0500 and 2300 and logs all output to the /var/log/smatool.log file. 
  */15 5-23 * * *   root cd /root/sma-bluetooth-0.17; ./smatool 2>&1 | logger -t smatool -p local5.info 
  

• activate the new cron entry:

  cp ./smatool.cron /etc/cron.d/smatool 
  chmod 744 /etc/cron.d/smatool 
  

• checkout /var/log/syslog for errors
• each run is logged in /var/log/syslog

The result:



Possible improvements:

• sma-bluetooth requires mysql which is a relatively heavy database for a plugpc. Sqlite would be a better choice. I experimented with the excellent fork http://rcphills-sma-bluetooth-dbabstraction.googlecode.com/ that supports sqlite, but the connection to pvoutput.org didn't work anymore.
• the current setup does too much I/O preventing the SATA HD to sleep. Unfortunately booting from an external USB flash disk is not easy on TP², so I'll have to investigate other alternatives.

Adding Bluetooth support to the TonidoPlug2

I'm planning to use my TonidoPlug2 (TP2) for reading out the electricity production of my solar panels. I attached a very small USB bluetooth dongle to my TP2. The USB bluetooth device is detected, but the default kernel has no bluetooth support:

root@TonidoPlug2:~# lsusb 
... 
Bus 001 Device 003: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth) 
... 

The only solution to this problem is to build a new TP2 kernel with bluetooth enabled. The next section details the specific steps that did the trick for me.

Important note: Do NOT change the kernel on the internal flash memory as it might brick your device! Configure your TP2 to boot from the SATA HD first. I created a dedicated 32GB boot partition on my SATA device. Details:

• best manual: http://www.tonido.com/communitywiki/doku.php?id=advanceduses:usbboot (pay special attention to the fdisk part as the TP2 can only boot from "msdos" partitions)
• other info: http://www.tonido.com/support/display/docs/Booting+off+USB+Drive

Once you are booting from the SATA HD, you can proceed with the instructions below.

Building a TP2 kernel with bluetooth

The arm-kernel can be built on a linux desktop. I used my regular Ubuntu laptop.

First start with building a normal TP2 kernel:

• http://www.tonido.com/support/display/docs/How+to+build+a+TonidoPlug2+kernel
• note that the url to download the kernel changed: http://www.tonidoplug.com/partners/topkick/2011/kernel/source/kernel-2.6.31-topkick1281p2-codelathe-20111122.tar.bz2

After you built the kernel and modules you can enable bluetooth by modifying the .config file:

   make menuconfig 

• Options to enable: (toggle by pressing 'space' until an * or M appears)
  • Networking → <*>Bluetooth subsystem support (CONFIG_BT)
  • Networking → Bluetooth subsystem support → <*>L2CAP protocol support (CONFIG_BT_L2CAP)
  • Networking → Bluetooth subsystem support → <*>SCO links support (CONFIG_BT_SCO)
  • Networking → Bluetooth subsystem support → <*>RFCOMM protocol support (CONFIG_BT_RFCOMM)
  • Networking → Bluetooth subsystem support → [*]RFCOMM TTY support (CONFIG_BT_RFCOMM_TTY)
  • Networking → Bluetooth subsystem support → <*>BNEP protocol support (CONFIG_BT_BNEP)
  • Networking → Bluetooth subsystem support → <*>HID protocol support (CONFIG_BT_HID)
  • Networking → Bluetooth subsystem support → Bluetooth device drivers → HCI USB driver (CONFIG_BT_HCIUSB)
• this is how my .config file was modified:

  ~/tonido/kernel-2.6.31$ diff .config.old .config 
  4c4 
  < # Sat May 12 21:21:58 2012 
  --- 
  > # Sat May 12 22:24:11 2012 
  654c654,673 
  < # CONFIG_BT is not set 
  --- 
  > CONFIG_BT=y 
  > CONFIG_BT_L2CAP=y 
  > CONFIG_BT_SCO=y 
  > CONFIG_BT_RFCOMM=y 
  > CONFIG_BT_RFCOMM_TTY=y 
  > CONFIG_BT_BNEP=y 
  > # CONFIG_BT_BNEP_MC_FILTER is not set 
  > # CONFIG_BT_BNEP_PROTO_FILTER is not set 
  > CONFIG_BT_HIDP=y 
  >  
  > # 
  > # Bluetooth device drivers 
  > # 
  > CONFIG_BT_HCIBTUSB=m 
  > # CONFIG_BT_HCIBTSDIO is not set 
  > # CONFIG_BT_HCIUART is not set 
  > # CONFIG_BT_HCIBCM203X is not set 
  > # CONFIG_BT_HCIBPA10X is not set 
  > # CONFIG_BT_HCIBFUSB is not set 
  > # CONFIG_BT_HCIVHCI is not set 
  1351a1371,1372 
  > CONFIG_HID_APPLE=y 
  > CONFIG_HID_WACOM=y 
  

You can continue with the instructions for building a TP2 kernel at step 15:

make uImage 
... 

Some attention points with the last activation step:

• remove two unnecessary symlinks before running scp:

  ~/tonido/kernel-2.6.31$ rm ../current_kernel/lib/modules/2.6.31.8-topkick1281p2-001-004-20101214/build 
  ~/tonido/kernel-2.6.31$ rm ../current_kernel/lib/modules/2.6.31.8-topkick1281p2-001-004-20101214/source 
  

• run scp (don't forget the -r for a directory):

  ~/tonido/kernel-2.6.31$ scp ../current_kernel/boot/uImage root@tp2-ip:/boot 
  ~/tonido/kernel-2.6.31$ scp -r ../current_kernel/lib/modules root@tp2-ip:/lib/ 
  

• double-check if all transfers were OK before rebooting

If the TP2 booted successfully you can now enable and test bluetooth:

• apt-get install bluez
• test with hcitool:

  root@TonidoPlug2:~# hcitool scan 
  Scanning ... 
   E4:D5:3D:EB:EA:E4 ubuntu-0 
   00:80:25:1F:9A:F4 SMA001d SN: ... 
  

Background info:

• forum thread on building a TP2 kernel: http://www.tonido.com/forum/viewtopic.php?f=37&t=4338&start=10
• generic instructions for setting up Bluetooth for the Linux kernel: http://www.thinkwiki.org/wiki/How_to_setup_Bluetooth#Configuring_the_kernel
• adding new modules for audio to the TP2 kernel: http://www.tonido.com/forum/viewtopic.php?f=37&t=4344

Ubuntu: Undeleting Files on FAT Partition

I accidentally deleted all photos on an SD card in my camera. Luckily, it is very easy to recover those deleted files on a FAT partition under Ubuntu. Simply install the excellent "testdisk" utility and run it from the command line:

sudo apt-get install testdisk 
testdisk

I was able to recover all files back from the SD card to my hard disk.

Instructions: http://www.cgsecurity.org/wiki/TestDisk:_undelete_file_for_FAT

Details: https://help.ubuntu.com/community/DataRecovery