We have already received some of the parts. Actually all the parts in my additional part list but not the Raspberry Pi B+ and the TBS1202B-EDU Oscilloscope.

Here are a couple of pictures of the boxes and modules:
EnOcean Pi Receiver Module
EnOcean Pi Module assembled on an Raspberry Pi
Next the Sensor Kit:




TCM 320C TRX Module to act as Actuator Receiver :
Connected using a 2mm Pitch connector on the board.


Raspberry Pi Camera and Web Server Raspberry Pi: This would be hanged on the wall of the drawing room.




Some more pictures of the working assembly for testing as of now:



Hope to post more pictures of the implementation as we go forward.
As part of our blogging for the Forget Me Not challenge we would first like to detail the idea that we wish to implmented.

SCHO – Safe Connected Home

An IoT based automation and energy efficient monitoring

This project is designed to provided connected control of house and security monitoring. Utilizing the energy efficient wireless network of sensors, switches and actuator outputs by EnOcean this project intends to provide a connected framework which can be remotely controlled using a mobile phone or using an internet gateway. The following are the objectives of SCHO design:
  • Control of electrical outlets from central server as well as wireless switch panels
  • Sensing of Doors and Windows for open/closed status
  • Sensing of soil moisture in the garden and motor actuation
  • Timed dispensing of water and food for the pet and reporting low stock situations
  • User control using Web API
  • Camera monitoring for image and video recording in case of security breach
  • SMS / Twitter status update and alert sending feature
Here is how it would be designed:
  • EnOceanPi with one Raspberry Pi B+ acts as the Wireless network central server
  • Additional Raspberry Pi helps to host the SMS gateway using 3G modem and the Web-server for Remote monitoring of the system Status
  • Both Raspberry Pi would communicate to internet using the home Wi-Fi network.
  • Front Door would be coupled with a STM320 Magnetic sensor sense its open-close status
  • A kitchen window would be coupled with another STM320 Magnetic sensor to sense its open-close status
  • The presence detection of the user would be ascertained using the MAC ID polling on the users Mobile with Wi-Fi connection via the Web-server Raspberry Pi. This would send an instruction to the EnOcean Raspberry Pi controlling the Wireless node network to turn off the Power outlets connected to the TCM 320 module system.
  • Another function of the Web-server Raspberry Pi B+ would be to use a Camera to monitor the front door for movement when the security system is armed. This would be done by the edge detection algorithm executing in python for each snap shot taken by the Raspberry Pi camera.
  • The power control would use two TCM320 modules in Mode 3 with 4 Relay control outputs. One of such output would be used to control the timed Cat feed actuation. Another output would be used to control the Garden water pump to water the plants in case the soil moisture goes below a threshold. Other outputs would be used to control the power plugs using relays. The complete control system housing the TCM320 and the relays would be powered from an external supply to help run the relays. 
  • The additional sensing function of the Soil Moisture and Load Cell on the Cat Feeder would be done using the STM 310 module. Two Soil moisture sensors would be used and one load cell would be used to achieve this.
  • The sensing actuation would be controlled using OpenHAB running on the Web-server Raspberry Pi to the EnOcean Raspberry Pi.

There are important assumptions made to achieve the functionality in time for the Challenge :
  • Soil humidity sensor would be emulated using a potentiometer
  • All the outputs from the TCM320C modules would be LEDs rather than the actual Relay's
  • The pressure input from the cat feeder would again be emulated using potentiometer.

All the above assumptions would help to complete the proof of concept first to help go the next step of actual field testing the rig.
We are pleased to announce our selection in to the highly anticipated Forget Me Not Challenge by Element 14.
This design challenge is all about solving your daily life worries about you house hold items and consumptions.
Some of the key questions that one asks in busy day to day life:
  • Did I leave the door unlocked?
  • Did I leave the iron on?
  • Did I water the plants?
  • DId I feed the cat?
These are the question that we are trying to provide a solution to help people not to worry any more about the mundane things and focus their attention on better parts needing their attention.

In this challenge the competitors would be provided with the best in class energy harvesting wireless control infrastructure by EnOcean in the form of their latest kit the EnOcean Raspberry Pi & Sensor Kit.
EnOcean Raspberry Pi Module
And you guessed it right we would be using the most popular Linux Board that created a new bread of makers - Raspberry Pi. And Element 14 has been generous enough to provide the latest B+ model for this challenge.
Raspberry Pi B+ Model


Not only Element 14 provides us with these goodies but they also provide us with Tektronix TBS1202B-EDU Oscilloscope and Eagle Cadsoft Pro 7 License.
Tektronix TBS1202B-EDU with 200MHz BW and 2G/s Sample Rate

Cadsoft Eagle Pro V7

Apart from this big lot of cool stuff from Element 14 we also get $500 budget to buy additional stuff from Element 14 to complete our entry.
Of course they are are great distributor of parts as well so off we go, implementing the next innovation worry-free-daily-life.

We wish to extend our thanks to Element 14, Tektronix, Raspberry Pi Foundation and EnOcean for organizing this amazing the challenge.
UPDATE 31st July 2014: There has been an issue our only Windows XP laptop has now crashed! So we have no other choice but have this post re-documented for Linux only.


We came across the LPC800 series of microcontroller from NXP. Actually it was an unused board lying in our closet of dev-boards. This is the NGX LPC800 Mini Kit. This board was a limited edition low cost kit part of the marketing campaign of LPC800 microcontrollers. Although there are much better boards to work with LPC800 we chose what we already had to try out this tiny ARM Cortex M0+ chip.
Image Courtesy lpcware.com
This is a nice tiny board with basic features to get started on LPC800. One thing that attracts us is the small PDIP package of the LPC810 microcontorller, more technically called as LPC810M021FN8. That's the exact part name of this chip if you would ever like to sample some from NXP.
On this board we have two buttons - one for Reset and another for ISP entery. Even though this board can be loaded with the LPC-Link or LPC-Link2 etc debuggers we prefer to use the cheaper route using a friendly USB-2-Serial adapters that we buy off ebay and Flash Magic tool. Although this would be a windows centric tutorial we would also provide a Linux alternative for this later, since that's our base system. For us we have been using windows under Virtual Box for some of the windows centric tools. The main problem with this board is that the LED that the board has is connected to the SWDIO pin which is used for debugging. This was the point we decided to do away with the debugger. Another important thing to note is that this board does not have a crystal on-board so the on-chip crystal oscillator needs to be used, this has implication in code we would discuss later. Lets have a quick look whats inside LPC800:
Image Courtesy lpcware.com
Well lets get started in our usual step by step way of running our first code on this microcontroller.

[1] Getting the Setup on Windows

First we would need to following to be downloaded:
Looks to be a long list of things, well this is much simpler than reading the complete datasheet and co-relating the User manual.

[2] Setting up the Environment


We would keep adding more as we go ...
This is an update for Building Android Kitkat from source on Ubuntu 13.10 for the latest version of the Android which android-4.4.2_r2 (Build: KVT49L) on the new 14.04 LTS version of Ubuntu.
We would be targeting this tutorial for the Nexus 5 device codenamed 'hammerhead', however similar procedure can be followed for Nexus 7C 2013('deb') or Nexus 7 ('Grouper').

As discussed in the previous post the procedure remains nearly the same. There are minor changes that would help to make this updated build work. But First:
DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 5 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

Now for the steps.

[0] PC and Other Requirements:

The basic system requirement are same as stated in the earlier post.

# PC configuration to have a decent build performance:
  • Processor: Quad Core 2.6GHz Intel Core i5 and above
  • RAM: 4GB DDR3 1066MHz and above
  • HDD Space: 120GB Free (build tools + Android source + build cache)
  • Internet Connection: 2mbps and above
# Nexus 5 with PC Cable

[1] Prepare Ubuntu 14.04 for building Android

The update package requirements from Ubuntu have changed so the particular step would need some correction to help install the required packages needed to build the Android Kitkat.

[1._ ] Most of the commands need to run in a terminal window so we need to open it before starting any of the below steps. The easy way on Ubuntu is to press the keyboard combination Ctrl + Alt + 't' else one can also go to the app launcher icon and type "terminal"

[1.a] Correcting and Installing Java

First thing that we need to perform is removing the Icedtea Java or OpenJDK
sudo apt-get purge openjdk-\* icedtea-\* icedtea6-\*

This time the problem is that we can not use the offical Java update from Oracle.
Instead we need to use the Last java version available in the JDK1.6 SE pacakge.
To do so one needs to signup at Oracle Java website: https://login.oracle.com/mysso/signon.jsp
After sign-up and login into the Oracle website use the JDK1.6SE u46 version link to get to the download area.
Now one needs to select the correct package:
Finally after downloading these files one needs to extract them and add to the path here are the commands:
chmod +x jdk-6u45-linux-x64.bin
./jdk-6u45-linux-x64.bin
echo "export PATH=$PATH :"`pwd`" >> $HOME/.bashrc
This would help to place the directory to path. Next there would be restart needed for the Terminal to enable the new path to take effect.
Note: If you have multiple Java installation then better ignore the last line and add it as per your requirement. We use both Java7 SE for application development and Java6 for Android. Hence we modify the path when needed.

[1.b] Installing the package dependencies into Ubuntu

This is a long an time taking process, where nearly 1050MByte+ data is downloaded. So be careful if you have limited bandwidth connection like ours. This might take up a lot of your Internet connection bandwidth.
sudo apt-get install git-core gnupg flex bison \
gperf build-essential zip curl \
zlib1g-dev zlib1g-dev:i386 libc6-dev \
lib32ncurses5-dev lib32ncurses5 \
lib32bz2-1.0 x11proto-core-dev \
libx11-dev:i386 libreadline6-dev:i386 \
lib32z1-dev libgl1-mesa-glx:i386 \
libgl1-mesa-dev g++-multilib mingw32 \
tofrodos python-markdown libxml2-utils \
xsltproc readline-common \
libreadline6-dev libreadline6 \
lib32readline-gplv2-dev libncurses5-dev \
lib32readline5 lib32readline6 \
libreadline-dev libreadline6-dev:i386 \
libreadline6:i386 bzip2 libbz2-dev \
libbz2-1.0 vim libghc-bzlib-dev \
lib32bz2-dev libsdl1.2-dev libesd0-dev \
squashfs-tools pngcrush schedtool \
libwxgtk2.8-dev python

This would update the base packages needed to compile the Android source.

This would take some time to get the complete download done and then the dependency fixes need to be applied:
sudo apt-get install -f
After this we need to do the following linking:
sudo ln -s /usr/lib/i386-linux-gnu/mesa/libGL.so.1 \
/usr/lib/i386-linux-gnu/libGL.so

This completes the installation of dependencies and necessary packages to begin our build

[2] Downloading the Google Repository tool - repo

In order to obtain the Android source code from Google there is a special tool called "repo". This tool enables us to download all the component repositories sources that come together to make Android OS source for a specific version.

First lets create a local directory which would hold our executable code:
mkdir ~/bin
Now let us download the repo tool into this directory and apply the executable permission:
curl http://commondatastorage.googleapis.com/git-repo-downloads/repo >\
~/bin/repo && chmod a+x ~/bin/repo


Finally adding this to the path to help us get the tool working
echo 'export PATH=$PATH:$HOME/bin' >> ~/.bashrc && \
source ~/.bashrc

We are now ready to obtain the source code from Google for Android OS

[3] Downloading the Android Sources & Vendor Binaries

For the Nexus 5 Device we have the 'hammerhead' Google code release:
Build: KVT49L
Repository Tag: android-4.4.2_r2

To start the download we need to first create a folder eg. android-4.4.2_r2
mkdir android-4.4.2_r2
cd android-4.4.2_r2


Now lets Initialize the Repository for GIT configuration
git config --global user.name {Your Name}
git config --global user.email {Your@Email}


This would set up your identity that would be part of this source code checkout
Finally we can Initialize the Repository using the following command:
repo init -u https://android.googlesource.com/platform/manifest -b android-4.4.2_r2
This command will take some time to finish as it creates the basis for the list of location from which the different components are downloaded.

Now we are ready to receive the real code:
repo sync -j4

The Vendor Specific Binaries located at :
https://developers.google.com/android/nexus/drivers

For 'hammerhead' and Android Kitkat Release download the binaries at this link:
https://developers.google.com/android/nexus/drivers#hammerheadkot49h


Go to the android-4.4.2_r2 directory and Download the drivers:
cd android-4.4.2_r2
wget -c https://dl.google.com/dl/android/aosp/broadcom-hammerhead-kot49h-a670ed75.tgz
wget -c https://dl.google.com/dl/android/aosp/lge-hammerhead-kot49h-e6165a67.tgz
wget -c https://dl.google.com/dl/android/aosp/qcom-hammerhead-kot49h-518133bf.tgz
tar -xvf broadcom-hammerhead-kot49h-a670ed75.tgz
tar -xvf lge-hammerhead-kot49h-e6165a67.tgz
tar -xvf qcom-hammerhead-kot49h-518133bf.tgz
rm *.tgz


Finally extract the Vendor Specific binaries by the following commands:
./extract-<filename>.sh
You need to enter the "I ACCEPT" at the end of license notices to execute the program.

Perform this for all the three files extracted above.

For 'Grouper' Nexus 7 these binaries are available at: https://developers.google.com/android/nexus/drivers#grouperkot49h

For 'deb' Nexus 7C 2013 these binaries are available at: https://developers.google.com/android/nexus/drivers#debkot49h

Now we are ready for the next big step - Compiling!

[4] Building the Sources

First open another Termial window and go the Android directory:
cd android-4.4.2_r2
. ./build/envsetup.sh


Now to select the type of device we give the following command:
lunch

This would display a menue:
You're building on Linux

Lunch menu... pick a combo:
     1. aosp_arm-eng
     2. aosp_x86-eng
     3. aosp_mips-eng
     4. vbox_x86-eng
     5. mini_x86-userdebug
     6. mini_armv7a_neon-userdebug
     7. mini_mips-userdebug
     8. aosp_tilapia-userdebug
     9. aosp_flo-userdebug
     10. aosp_deb-userdebug
     11. aosp_grouper-userdebug
     12. aosp_manta-userdebug
     13. aosp_hammerhead-userdebug
     14. aosp_mako-userdebug

Which would you like? [aosp_arm-eng] 13


Select the option '13. aosp_hammerhead-userdebug' choice by entering '13'.
Now we are ready to start the build.
make -j4

Here the "-j4" switch would help to run the build on Quad core.

This process would take some time ranging from 30minutes to 3hours depending of your PC performance and configuration.
After this is done you are ready with your source to flash the image into your device.
DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 5 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

[5] Flashing the Device

This would definitely damage your device and load the image of Android OS built in the previous steps. In order to perform this step one needs to unlock the bootloader as explained in the XDA forum post.
Connect your device into the Linux PC. And give the command in the existing terminal prompt from the earlier step.
adb root
adb reboot bootloader
cd out/target/product/grouper


This would help you enter the bootloader mode. And change the directory to the place where the actual build image files are located
Final command that would kill the device and load your compiled image:
fastboot oem unlock && fastboot -w flashall

This would load the complete image into your device and then reboots it.

Now in order to restore the device back to its original os follow the steps outline in another post. Although this is for the Nexus 7 device the similar steps work for Nexus 5 device also.
We were evaluating different IDE's for development with our newly acquired STM32 board that we posted about earlier and a new Stellaris Launchpad . The initial example that we covered was completed in Keil environment. Next we wanted to extend beyond the 32KByte limit imposed by Keil so we need to look for alternatives. Although we were quite happy with coocox IDE, we needed some thing with lot more debugging options. Even though the CCS IDE from TI is good but for older PC's like ours its difficult. This lead us to work with Keil, but under the hood GCC would do the heavy lifting.

We would explain the process of compiling for thee different ARM Cortex-M3 architectures and all that you would need to get started on that.

UPDATE 19,Apr 2014: There has been some changes to the STM32 Standard Libs location
Recently we discovered the long awaited MSP430GCC which was released in support with RedHat and TI . It was disclosed in the sourceforge MSP430GCC website notice on 26th October, 2012 . Well we were hoping since a long time that this release to be out. It seams that last year in December'2013 the first version was released.
The MSP430GCC is officially supported in the beta version of the CSSv6. This can be installed using the new TI AppCenter feature.
This feature of CCSv6 helps to install the required software features such as GCC and MSP430Ware directly from the CCS IDE. TI has also included support for Energia in this latest beta release. The sketches of Energia can be directly composed in CCS IDE along with the native CCS projects. We have not tested this feature and would be posting more on the review of all the features of the CCSv6.
The only problem we found was that the CCSv6 now requires a online installation which consumes roughly 460MB of internet bandwidth for download not including the MSP430Ware and MSP430GCC. They are downloaded separately after the installation of the CCS itself through the AppCenter.

MSP430GCC can also be individually installed for Windows and Linux , for normal operation using makefiles like the older times. However there is a need to download additional device header files and install them into correct path so that during the make these files get included correctly. However inside the CCS environment this is take care directly. The links for the download location are mentioned below. We would be covering this new MSP430GCC compiler in our next review.

We would like to thank TI and RedHat for bringing the MSP430GCC release.

Here are the relevant links

MSP430GCC Download for Windows and Linux :
http://software-dl.ti.com/msp430/msp430_public_sw/mcu/msp430/MSPGCC/1_00_00_00/index_FDS.html
Note: Under Linux the installation file downloaded needs to be first made executable using the 'chmod +x FileName.run' command. And later the installation needs to be run in super user mode using the 'sudo ./FileName.run' command. Here the FileName would change as per the installation file downloaded.

MSP430GCC Device Specific Header files Download:
http://software-dl.ti.com/msp430/msp430_public_sw/mcu/msp430/MSPGCC/1_00_00_00/exports/GCC_RH_20131206.zip

CCSv6 Download for Windows and Linux :
http://processors.wiki.ti.com/index.php/CCSv6
We were investigating a way to make some automation for file generation and tried to use python to solve our problems. Doing so we found an interesting way to use python scripts.
Our python scripts were stored in various directories below a root directory.
It looked some thing like this:







Each of the directories contained several scripts that would generate corresponding pages for a website. This would mean that we need to parse the directory tree and then run the Scripts. That was done using the 'walk' function available as part of the 'os' Package. Here is the code for the function:

Another thing that was done in this function was that some time due to inclusion of the sub-modules the '__pycache__' is create or there are '__init__.py' files for packages that would not be executed.

Next we need the way to run the Python sctipts using the above 'runner' function. For this there are three ways to go about. This completely depends on the way in which the script is called , its dependencies and possible case of individual or ' Runner' execution. We decided to write for all the different ways.

In this snippet depending on the variable 'bDirect' the way of execution is decided.

  • The option 0 calls the module by using the internal interpreter function 'exec' after compiling the script.
    In this case the environment of the Caller eg. the Runner function would be completely inherited.
  • The option 1 executes the script in command line. This is same a going to each of the directories and then executing the files individually. This case no environment can be inherited. Each script is responsible for seting up its required environment for execution.
  • The option 2 executes a specific function called 'run()' defined in each of the script files. In this the script being run inherits only the Path and not any other entity. This call is similar to calling any function in any other module or package. However the user program now has a way to pass parameters to the scripts which may include local / global variables, generators or even functions.
Here is the complete program for this we call it the 'main.py' and is placed in the root for the folder:

Still there is one problem that remains , how to detect if the python scripts are being executed from the Runner or are being directly executed. As this would effect the environment initialization. To solve this we created a example script that could be used to test its own environment and be able to set up the environment in case its not being run from the 'Runner' script.

This Example program how to create the scripts in the directories such that they can either run using the Runner or directly. The 'config ' here is a package that contain the configuration data for each of the scripts. So relative paths can be used to correct the errors in case the files are run directly.

Hope that this tip would be helpful, let us know your comments if you like this.

This is an update from our last post of Building Android from Source for Nexus 7 on Ubuntu 13.04 : Step-by-Step. This time we upgrade our Ubuntu Installation to 13.10 Saucy Salamander along with the update Android Version 4.4 KitKat for the Latest Nexus 5 device code named 'hammerhead'.
UPDATE: New build instructions for Ubuntu 14.04 LTS version
As discussed in the previous post the procedure remains nearly the same. There are minor changes that would help to make this updated build work. But First:
DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 5 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

Now for the steps.

[0] PC and Other Requirements:

The basic system requirement are same as stated in the earlier post.

# PC configuration to have a decent build performance:
  • Processor: Quad Core 2.6GHz Intel Core i5 and above
  • RAM: 4GB DDR3 1066MHz and above
  • HDD Space: 120GB Free (build tools + Android source + build cache)
  • Internet Connection: 2mbps and above
# Nexus 5 with PC Cable

[1] Prepare Ubuntu 13.10 for building Android

The update package requirements from Ubuntu have changed so the particular step would need some correction to help install the required packages needed to build the Android Kitkat.

[1._ ] Most of the commands need to run in a terminal window so we need to open it before starting any of the below steps. The easy way on Ubuntu is to press the keyboard combination Ctrl + Alt + 't' else one can also go to the app launcher icon and type "terminal"

[1.a] Correcting and Installing Java

First thing that we need to perform is removing the Icedtea Java or OpenJDK
sudo apt-get purge openjdk-\* icedtea-\* icedtea6-\*

This time the problem is that we can not use the offical Java update from Oracle.
Instead we need to use the Last java version available in the JDK1.6 SE pacakge.
To do so one needs to signup at Oracle Java website: https://login.oracle.com/mysso/signon.jsp
After sign-up and login into the Oracle website use the JDK1.6SE u46 version link to get to the download area.
Now one needs to select the correct package:
Finally after downloading these files one needs to extract them and add to the path here are the commands:
chmod +x jdk-6u45-linux-x64.bin
./jdk-6u45-linux-x64.bin
echo "export PATH=$PATH :"`pwd`" >> $HOME/.bashrc
This would help to place the directory to path. Next there would be restart needed for the Terminal to enable the new path to take effect.
Note: If you have multiple Java installation then better ignore the last line and add it as per your requirement. We use both Java7 SE for application development and Java6 for Android. Hence we modify the path when needed.

[1.b] Installing the package dependencies into Ubuntu

This is a long an time taking process, where nearly 1050MByte+ data is downloaded. So be careful if you have limited bandwidth connection like ours. This might take up a lot of your Internet connection bandwidth.
sudo apt-get install git-core gnupg flex bison \
gperf build-essential zip curl \
zlib1g-dev zlib1g-dev:i386 libc6-dev \
lib32ncurses5-dev lib32ncurses5 \
lib32bz2-1.0 x11proto-core-dev \
libx11-dev:i386 libreadline6-dev:i386 \
lib32z1-dev libgl1-mesa-glx:i386 \
libgl1-mesa-dev g++-multilib mingw32 \
tofrodos python-markdown libxml2-utils \
xsltproc readline-common \
libreadline6-dev libreadline6 \
lib32readline-gplv2-dev libncurses5-dev \
lib32readline5 lib32readline6 \
libreadline-dev libreadline6-dev:i386 \
libreadline6:i386 bzip2 libbz2-dev \
libbz2-1.0 vim libghc-bzlib-dev \
lib32bz2-dev libsdl1.2-dev libesd0-dev \
squashfs-tools pngcrush schedtool \
libwxgtk2.8-dev python

This would update the base packages needed to compile the Android source.

This would take some time to get the complete download done and then the dependency fixes need to be applied:
sudo apt-get install -f
After this we need to do the following linking:
sudo ln -s /usr/lib/i386-linux-gnu/mesa/libGL.so.1 \
/usr/lib/i386-linux-gnu/libGL.so

This completes the installation of dependencies and necessary packages to begin our build

[2] Downloading the Google Repository tool - repo

In order to obtain the Android source code from Google there is a special tool called "repo". This tool enables us to download all the component repositories sources that come together to make Android OS source for a specific version.

First lets create a local directory which would hold our executable code:
mkdir ~/bin
Now let us download the repo tool into this directory and apply the executable permission:
curl http://commondatastorage.googleapis.com/git-repo-downloads/repo >\
~/bin/repo && chmod a+x ~/bin/repo


Finally adding this to the path to help us get the tool working
echo 'export PATH=$PATH:$HOME/bin' >> ~/.bashrc && \
source ~/.bashrc

We are now ready to obtain the source code from Google for Android OS

[3] Downloading the Android Sources & Vendor Binaries

For the Nexus 5 Device we have the 'hammerhead' Google code release:
Build: KRT16M
Repository Tag: android-4.4_r1

To start the download we need to first create a folder eg. android-4.4_r1
mkdir android-4.4_r1
cd android-4.4_r1


Now lets Initialize the Repository for GIT configuration
git config --global user.name {Your Name}
git config --global user.email {Your@Email}


This would set up your identity that would be part of this source code checkout
Finally we can Initialize the Repository using the following command:
repo init -u https://android.googlesource.com/platform/manifest -b android-4.4_r1
This command will take some time to finish as it creates the basis for the list of location from which the different components are downloaded.

Now we are ready to receive the real code:
repo sync -j4

The Vendor Specific Binaries located at :
https://developers.google.com/android/nexus/drivers

For 'hammerhead' and Android Kitkat Release download the binaries at this link:
https://developers.google.com/android/nexus/drivers#hammerheadkrt16m

Go to the android-4.4_r1 directory and Download the drivers:
cd android-4.4_r1
wget -c https://dl.google.com/dl/android/aosp/broadcom-hammerhead-krt16m-bf9b8548.tgz
wget -c https://dl.google.com/dl/android/aosp/lge-hammerhead-krt16m-0efa9c33.tgz
wget -c https://dl.google.com/dl/android/aosp/qcom-hammerhead-krt16m-53cf1896.tgz
tar -xvf broadcom-hammerhead-krt16m-bf9b8548.tgz
tar -xvf lge-hammerhead-krt16m-0efa9c33.tgz
tar -xvf qcom-hammerhead-krt16m-53cf1896.tgz
rm *.tgz


Finally extract the Vendor Specific binaries by the following commands:
./extract-<filename>.sh
You need to enter the "I ACCEPT" at the end of license notices to execute the program.

Perform this for all the three files extracted above.
Now we are ready for the next big step - Compiling!

[4] Building the Sources

First open another Termial window and go the Android directory:
cd android-4.4_r1
. ./build/envsetup.sh


Now to select the type of device we give the following command:
lunch

This would display a menue:
You're building on Linux

Lunch menu... pick a combo:
     1. aosp_arm-eng
     2. aosp_x86-eng
     3. aosp_mips-eng
     4. vbox_x86-eng
     5. mini_x86-userdebug
     6. mini_armv7a_neon-userdebug
     7. mini_mips-userdebug
     8. aosp_tilapia-userdebug
     9. aosp_flo-userdebug
     10. aosp_deb-userdebug
     11. aosp_grouper-userdebug
     12. aosp_manta-userdebug
     13. aosp_hammerhead-userdebug
     14. aosp_mako-userdebug

Which would you like? [aosp_arm-eng] 13


Select the option '13. aosp_hammerhead-userdebug' choice by entering '13'.
Now we are ready to start the build.
make -j4

Here the "-j4" switch would help to run the build on Quad core.

This process would take some time ranging from 30minutes to 3hours depending of your PC performance and configuration.
After this is done you are ready with your source to flash the image into your device.
DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 5 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

[5] Flashing the Device

This would definitely damage your device and load the image of Android OS built in the previous steps. In order to perform this step one needs to unlock the bootloader as explained in the XDA forum post.
Connect your device into the Linux PC. And give the command in the existing terminal prompt from the earlier step.
adb root
adb reboot bootloader
cd out/target/product/grouper


This would help you enter the bootloader mode. And change the directory to the place where the actual build image files are located
Final command that would kill the device and load your compiled image:
fastboot oem unlock && fastboot -w flashall

This would load the complete image into your device and then reboots it.

Now in order to restore the device back to its original os follow the steps outline in another post. Although this is for the Nexus 7 device the similar steps work for Nexus 5 device also.
We have been working on some Java based projects recently. The compile mechanism of Java is a bit different from the way each of the IDEs implement them. We have used Netbeans-IDE and Eclipse. We figured that both have radically different way of implementing the compile time and jar time constrains. However we wanted some thing as simple as "make clean" and "make compile". That's when we came across Ant.

Apache Ant is internal build system used by many of the IDEs, this is the build framework in the world of Java. Kind of like 'make' for Java but apparently bit easier than makefiles. We need a consistent build framework across our Linux, Mac OS and Windows. We made a generic build system and configured in the way to make building Java projects a breeze.

In this article we would be discussing how we went about setting up the all the three system to have a common build framework for our up coming project jNeelSer which would be detailed later.

[1] Obtain Java

The  Ant framework is written in Java and hence to execute the same we would need to have Java compiler and run time available. To do this we simply get the JDK and place it into our path.
One can obtain the Java SE JDK from the Oracle Website. For now one can use the Latest JDK Java SE 7 releases.
A word of caution for the Linux users - if one intend to use the JDK to compile Android and use it for general purpose Java programming then they need to have JDK 6 version separately for Android from the Oracle Java Archive and if JDK 7 is used for development then the Path needs to appended accordingly. We actually do this so we will show how to do this in the next steps.

[2] Obtain Ant

The Ant package is available in binary form at Apache Ant website. Its designed in such a way that one can easily run it in any platform. So to setup extract the Ant package into the desired directory.
We are using Ant 1.9.2. So we have the directory apache-ant-1.9.2/bin and we add this to our Path in all the three platforms. Its easy to understand the Zipped version is for windows and the .tar.gz & .tar.bz2 are for Linux or MacOS.

[3] Ant Environment Script

In order the Ant build system to work one needs to setup the system Environment in the correct way.
Lets try to spend a moment to understand the system variable and what they mean:
  • JAVA_HOME = Location of the Java Installed Directory. Not the 'bin' directory but the root directory of Java installation.
    Eg. JAVA_HOME=C:\jdk1.6.0_45 and not C:\jdk1.6.0_45\bin
  • ANT_HOME = Location of the Ant Installed Directory. Again not the 'bin' but the extracted directory.
    Eg. ANT_HOME=/home/efb/local/apache-ant-1.9.2 and not /home/efb/local/apache-ant-1.9.2/bin
  • PATH = Need to be modified to add the Ant as well as Java ahead of all parsing. We will show this how
 Now lets look at how we can configure these environment variables:
Windows Batch file script (Save this text into a .bat file replacing the 'path' strings):
For Linux / MacOS we can create a small shell script to do this:
However this also means that the file needs to executable, so below is the command:
chmod +x antconf.sh

Next lets progress with writing a simple build script.

[4] Writing the Build Script for Ant

The Ant build framework is written in Java and uses XML based format to write the build scripts. This is a complete paradigm shift from the conventional Makefile business that we have seen countless number of times. Have a look at the basic framework of the build script:

Here the first XML tag defines the usual DTD as per the W3C. This is similar to the one used in any conventional XML data file.
Next the header <Project> gives details about the project that we plan to compile/build. Its important to remember the name specified by the parameter 'name="jNeelSer"' gives the project its true name. The compiled output would use this parameter to name the file build output.
The parameter 'basedir="."' helps to determine the path to the source code base where the build.xml is present.

Forgot to mention that  build.xml is the default name of the build script for Ant.

The 'default="compile"' option helps to determine the default step to be performed when the build is invoked.
Here is the complete source for the jNeelSerial project, we would use this as an example to detail the way of writing the Ant build script.
In the above build script there are many additional tags that help to define more information about the project and help in correct build generation.
  • Fail tag shown in line 26 is used to declare that one can use this build script with 1.8.0 or higher version of Ant build.
  • Property Tag shown in line 34 is used to fine the source and build location directories using the location value. The Property tag can also have other values if needed.
  • Target Tag shown in line 38 is like a configuration which contains a set of actions to be perfomed when the build is invoked. One can also add some description to each of the targets if needed as shown in the Compile configuration. Lets have a detailed look at this:
    • Init configuration: This is the Initial target that helps to create the necessary directories or build related info before hand.
    • Compile configuration: This is used to actually build the classes for the source code with the correct Class path. This build target need to run the Init in case it was not explicitly called.
    • jar configuration: This is used to generate the executable manifest information and create the required JAR file that contains the supporting libraries in one place. jNeelSerial uses the jSSC library stored in the lib directory. Again Jar depends on the Compile configuration as the class files to be packaged need to be available.
    • clean configuration: This is used to clear the build and intermediate directories.
  • mkdir Tag shown in line 42 helps to create directories with reference to build.xml file directory path as the reference.
  • delete Tag shown in line 67 can be used to delete files(use file attribute) or directories (use dir attribute)
  • javac Tag shown in line 48 is the most important tag that actually performs the compilation. The srcdir attribute helps to locate the java source code. The destdir attribute specified the location where the compiled classes should be placed. The includeantruntime attribute helps to run the java compilation under ant system control to help produce useful output of the commands being executed.
    • Classpath Tag in line 49 helps to define and include the necessary classes/packages and their locations. It require the Pathelement Tag to declare the paths. There can be two types - Package/Class locations(Eg. Line 50) or Absolute includes (Eg. Line 51)
  • jar Tag shown in line 58 is used to generate the executable java archive. In this the destfile attribute defines the destination jar file and the basedir attribute specifies the location for the class files complied earlier.
    • Manifest Tag in line 59 is used to define the default executable class which contains the 'main'. This is achived by using the Attribute Tag for 'Main-Class' with the value of the exact class with namespace.
    • zipgroupfileset Tag in line 62 helps to include some additional files if needed into the final jar. In the above example shows how to specify the directory and include files using a wildcard sequence.
This concludes the description of he build script.
Now how to run this thing.

[5] Running the Build

In order to run the build, first we need to use the scripts that we wrote earlier to setup the Ant build environment inside a Terminal window. Then change directory to the desired project directory and run the ant command.
Here is the syntax:
ant [target]
Here the important point is that [target] should be a valid one specified in the build.xml file. And this is run in the directory of the project containing the build.xml file.
In our above example for jNeelSerial there are 3 main targets - compile, jar and clean
In case the file name of the build script is different then use the following syntax:
ant -f [build script.xml] [target]

For example in jNeelSerial the name of the build script is make.xml and hence the command would be:
ant -f make.xml compile

Hope that you like this tutorial, let us know your feedback on this article.
This is in continuation to our earlier article "Building Android from Source for Nexus 7 on Ubuntu 13.04 : Step-by-Step" where we discussed on how to build a complete android distro. This article focuses on restoring the Nexus 7 [2012] Wifi (grouper) device to the official version of android.

This process would completely format the Grouper device and the user would lose all the data.
DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 7 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

[1] Download the official Android Build

First step is to obtain the latest version of the Android OS. In order to do so we would need to visit the Google Factory Images Page At: https://developers.google.com/android/nexus/images
The correct Latest Android OS Image for Grouper is:
Official Name: nakasig
Android Version: 4.3
Build: JWR66V (more details from on Build Code Name page )
Link: http://developers.google.com/android/nexus/images#nakasijwr66v
Download Link: https://dl.google.com/dl/android/aosp/nakasig-jwr66v-factory-aebc7b11.tgz

After this extract this file into a directory just above the 'android-4.3_r1' created earlier.
In order to extract issue the following command in Ubuntu Linux Terminal prompt at the directory where the above downloaded file ".tgz" is located.

tar -xvf nakasig-jwr66v-factory-aebc7b11.tgz

This would create a directory called "nakasi-jwr66v" which would contain the required files to flash the factory Android image.

[2] Setting up and Download

 Now its time that we setup the environment to load the Image. Before we begin the Nexus 7 grouper device needs to be plugged to the Ubuntu machine. And the Android build that we did earlier needs to be present or the Android SDK must be in the path.

We will assume that you have the earlier Android build, else one can skip the steps given below if you have the Android SDK:
cd android-4.3_r1
. ./build/envsetup.sh
lunch 6

cd ..

Now we are ready to move with the installation step:

adb reboot bootloader

This would help to go into the Boot loader mode.
Now we need to go to the directory where the offical android build was extracted. And then run the command to flash the image:

cd nakasi-jwr66v
./flash-all.sh


This would format the complete flash and then load a fresh copy of the Official Android build.
Finally the device would reboot on its own and would ask for the default setup needed to get the device running.

Hope that you liked our articles, let us know your comments and suggestions to improve them.
Next we would be posting on how to develop some basic low level apps in Android.
We have been kept busy with our research work on Android operating system for mobile phones. We thought it would be nice to share a short tutorial to get started on building the Android source from scratch. There were several hurdles to pass before we could really get some thing working. Our target platform was Nexus 7 or what is called as "grouper" in Android terms.

Updated for Nexus 5 Source build on Ubuntu 13.10 >>

Nexus 7 is fairly a cheap device for now, as compared to the other high end phones. For disambiguation we are using a Nexus 7 with 16GB Storage and Only Wi-Fi. Since there are two variants available in the market, this one is called as "grouper".
However off the shelf devices are not the development units so you need to mod it to work as a development device. Here we would like to issue a warning.

DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 7 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

[0] PC and Other Requirements:

# PC configuration to have a decent build performance:
  • Processor: Quad Core 2.6GHz Intel Core i5 and above
  • RAM: 4GB DDR3 1066MHz and above
  • HDD Space: 120GB Free (build tools + Android source + build cache)
  • Internet Connection: 2mbps and above
# Nexus 7 with PC Cable
# Lots of patience and 1 day time ;-)

[1] Prepare Ubuntu 13.04 for building Android

In order to prepare the standard Ubuntu operation you can first update the installation to the most recent packages. Next follow the steps to install and configure the build system. Thanks to the Blog: soupdawg.wordpress.com
[1._ ] Most of the commands need to run in a terminal window so we need to open it before starting any of the below steps. The easy way on Ubuntu is to press the keyboard combination Ctrl + Alt + 't' else one can also go to the app launcher icon and type "terminal"

[1.a] Correcting and Installing Java

First thing that we need to perform is removing the Icedtea Java or OpenJDK
sudo apt-get purge openjdk-\* icedtea-\* icedtea6-\*
Next we need to add the official last JDK from Oracle:
sudo add-apt-repository ppa:webupd8team/java
Next perform an update on Apt Sources:
sudo apt-get update
Finally Install the Java6 version of JDK:
sudo apt-get install oracle-java6-installer
Just to make sure that you have the right stuff you run the following command:
java -version
The output would be something like:
java version “1.6.0_39″
Java(TM) SE Runtime Environment (build 1.6.0_39-b04)
Java HotSpot(TM) 64-Bit Server VM (build 20.14-b01, mixed mode)
So now we are done with Java which is one of the essential components needed by the Android Dalvik compiler

[1.b] Installing the package dependencies into Ubuntu

This is a long an time taking process, where nearly 900MByte+ data is downloaded. So be careful if you have limited bandwidth connection like ours. This might take up a lot of your Internet connection bandwidth.
sudo apt-get install git-core gnupg flex bison gperf \
build-essential zip curl zlib1g-dev zlib1g-dev:i386 \
libc6-dev lib32ncurses5-dev ia32-libs x11proto-core-dev \
libx11-dev:i386 libreadline6-dev:i386 lib32z1-dev \
libgl1-mesa-glx:i386 libgl1-mesa-dev g++-multilib \
mingw32 tofrodos python-markdown libxml2-utils \
xsltproc readline-common libreadline6-dev libreadline6 \
lib32readline-gplv2-dev libncurses5-dev lib32readline5 \
lib32readline6 libreadline-dev libreadline6-dev:i386 \
libreadline6:i386 bzip2 libbz2-dev libbz2-1.0 vim \
libghc-bzlib-dev lib32bz2-dev libsdl1.2-dev libesd0-dev \
squashfs-tools pngcrush schedtool libwxgtk2.8-dev python
This would take some time to get the complete download done and then the dependency fixes need to be applied:
sudo apt-get install -f
After this we need to do the following linking:
sudo ln -s /usr/lib/i386-linux-gnu/mesa/libGL.so.1 \
/usr/lib/i386-linux-gnu/libGL.so
This completes the installation of dependencies and necessary packaes to begin our build

[2] Downloading the Google Repository tool - repo

In order to obtain the Android source code from Google there is a special tool called "repo". This tool enables us to download all the component repositories sources that come together to make Android OS source for a specific version.
First lets create a local directory which would hold our executable code:
mkdir ~/bin
Now let us download the repo tool into this directory and apply the executable permission:
curl https://dl-ssl.google.com/dl/googlesource/git-repo/repo >\
~/bin/repo && chmod a+x ~/bin/repo
Finally adding this to the path to help us get the tool working
echo 'export PATH=$PATH:$HOME/bin' >> ~/.bashrc && \
source ~/.bashrc
We are now ready to obtain the source code from Google for Android OS

[3] Understanding and Downloading the Android Sources

There are multiple sources to obtain the Android OS source code. Here are a few of them:
1. Android Open Source Project - AOSP : This is the Google's official development project for android which would be detailed in this tutorial
2. AOKP from Team KANG : Offshoot with all bells-n-whistles loaded plus additional functionality
3. CyanogenMod : This project provides the complete Bootloader customization with specific Recovery and Andorid OS source integration. Slightly old but widely used to replace the official bootloader and recovery tool.

Digging deeper into the AOSP project we now need to know what are the Android OS distributions and what would be most suited towards our "grouper" device.
http://source.android.com/source/build-numbers.html
For now we would choose:
Build: JWR66V  
Repository Tag: android-4.3_r1
This is compatible to the "grouper" device so its a safe bet, there are others but possibly dont have official support for our target device.

UPDATE[4-Oct-2013] Latest version compatible for "grouper" is:
Build: JWR66Y
Repositrory Tag: android-4.3_r1.1
Please update the below commands and branch names accordingly

UPDATE[10-Nov-2013] Latest version compatible for "grouper" is:
Build: KRT16S
Repository Tag: android-4.4_r1.2
Finally we have Kitkat also for "grouper", thank to the signing campaign.
Update procedure for Kitkat have been published in another post

[3.a] Downloading the Source

To start the download we need to first create a folder eg. android-4.3_r1
mkdir android-4.3_r1
cd android-4.3_r1
Now lets Initialize the Repository for GIT configuration
git config --global user.name {Your Name}
git config --global user.email {Your@Email}
This would set up your identity that would be part of this source code checkout

Finally we can Initialize the Repository using the following command:
repo init -u https://android.googlesource.com/platform/manifest -b android-4.3_r1

The anatomy of this command is:
repo = Command
init = For Initialization
-u https://android.googlesource.com/platform/manifest = Location for all the source
-b android-4.3_r1 = Specific branch of source code that needs to be picked

This command will take some time to finish as it creates the basis for the list of location from which the different components are downloaded.

Now we are ready to receive the real code:
repo sync -j4

The anatomy of the command is:
repo = Command
sync = Download the code
-j4 = Use Quad core processing for downloading the source code

Once this command is completed you have the basic android source code available. Just to be sure that you have not missed any files try to run this command again. In case the download fails due to some reason you can ask for another download to fix any issues.
Once suggestion would be back up this basic source to have a copy that you can use to get back the older stage. Use this command to create the backup: (OPTIONAL)
cd .. && tar -jcvf android-4.3_r1_INIT.tar.bz2 --exclude ".git" \
--exclude ".repo" --exclude ".svn" android-4.3_r1/

[3.b] Getting Vendor Specific Binaries

In order to support the various sub-components in the "grouper" we would need to have the vendor binaries. These help to enable functionality + FW needed for the additional processors in the system.
One can find more info on this from the following link:
https://developers.google.com/android/nexus/drivers

For "grouper" and Android JBMR2 release download the binaries from the below location:
https://developers.google.com/android/nexus/drivers#grouperjwr66v

Download all the driver binaries into the android-4.3_r1 directory:
cd android-4.3_r1
wget -c https://dl.google.com/dl/android/aosp/asus-grouper-jwr66v-15547c77.tgz
wget -c https://dl.google.com/dl/android/aosp/broadcom-grouper-jwr66v-fa38dae8.tgz
wget -c https://dl.google.com/dl/android/aosp/elan-grouper-jwr66v-4235892f.tgz
wget -c https://dl.google.com/dl/android/aosp/invensense-grouper-jwr66v-0da5128c.tgz
wget -c https://dl.google.com/dl/android/aosp/nvidia-grouper-jwr66v-2cbbe013.tgz
wget -c https://dl.google.com/dl/android/aosp/nxp-grouper-jwr66v-202ba26a.tgz
wget -c https://dl.google.com/dl/android/aosp/widevine-grouper-jwr66v-c6bdbc54.tgz
tar -xvf asus-grouper-jwr66v-15547c77.tgz
tar -xvf broadcom-grouper-jwr66v-fa38dae8.tgz
tar -xvf elan-grouper-jwr66v-4235892f.tgz
tar -xvf invensense-grouper-jwr66v-0da5128c.tgz
tar -xvf nvidia-grouper-jwr66v-2cbbe013.tgz
tar -xvf nxp-grouper-jwr66v-202ba26a.tgz
tar -xvf nxp-grouper-jwr66v-202ba26a.tgz
rm *.tgz

Optionally create a backup for these shell scripts extracted:
cd ..
tar -jcvf Nexus7Binaries.tar.bz2 ./android-4.3_r1/*.sh
cd android-4.3_r1

[3.c] Extracting the Vendor Specific Binaries

In order to install the vendor specific binaries one needs to run the .sh files generated by extracting the .tgz files in the earlier step.
The method to run the shell files:
.\extract-<filename>.sh
Once you run them you would get a prompt to read the License agreement, press Enter to start reading and then Space bar to reach the end. Finally you need to type "I ACCEPT" to make the script extract the files. Finally the 'Vendor' directory would be ready after this step
Now we are ready for the next big step - Compiling!

[4] Building the Sources

First thing to do is to setup the Environment:
cd android-4.3_r1
. ./build/envsetup.sh

Anatomy of the command
'. ' = Signifies that we would be implying to execute the command in the current shell context
./build/envsetup.sh = Command to setup the environment variables and commands

Now to select the type of device we give the following command:
lunch

This would display some selection menu like:

You're building on Linux

Lunch menu... pick a combo:
     1. aosp_arm-eng
     2. aosp_x86-eng
     3. aosp_mips-eng
     4. vbox_x86-eng
     5. aosp_flo-userdebug
     6. full_grouper-userdebug
     7. full_tilapia-userdebug
     8. mini_armv7a_neon-userdebug
     9. mini_mips-userdebug
     10. mini_x86-userdebug
     11. full_mako-userdebug
     12. full_maguro-userdebug
     13. full_manta-userdebug
     14. full_arndale-userdebug
     15. full_toroplus-userdebug
     16. full_toro-userdebug
     17. full_panda-userdebug

Which would you like? [aosp_arm-eng]

For this you need to select the " 6. full_grouper-userdebug" choice by entering '6'
It would display the details of the selected "grouper" hardware.

Next major Step is to initiate big build process. This build process would take approximately 2hours 45minutes to complete on the machine specified above. If one has i7 then they can get even faster builds.
This command is:
make -j4

Here the "-j4" switch would help to run the build on Quad core.
After this is done you are ready with your source to flash the image into your device.

DISCLAIMER: If you proceed on the steps provided it will surely cause damage to your Nexus 7 device and the Author of this article will not be held responsible for any losses or damages of any type caused by following the steps below.

[5] Flashing the Device

This would definitely damage your device and load the image of Android OS built in the previous steps.In order to perform this step one needs to unlock the bootloader as explained in the XDA forum post.
Connect your device into the Linux PC. And give the command in the existing terminal prompt from the earlier step.
adb root
adb reboot bootloader
cd out/target/product/grouper

This would help you enter the bootloader mode. And change the directory to the place where the actual build image files are located

Final command that would kill the device and load your compiled image:
fastboot oem unlock && fastboot -w flashall

This would load the complete image into your device and then reboots it.
Now that you have successfully built and flashed the code you might not find it very useful until you add all the bells-n-whistles that a professional rom has. We would try to cover that in our next tutorial. Also next tutorials we have described how to restore the factory image.
Hope that you find this post helpful, let us know your feedback and suggestions.
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