Raspberry Pi – Part II – Get Up and Going with Java

In recent weeks, I haven’t revisited the Raspberry Pi – Running, Vacation, Work have conspired to keep me away from hobby project.

I’ve stared at the parts long enough, and decide to plug the Raspberry Pi base into the wired network. I plugged in the Raspberry Pi into the Power outlet, and I got the Red Light.  I logged into my router to see if the Pi picked up the Raspberry Pi, and I found the IP from my routers IP reservations table.   I was able to SSH into the Pi and quickly check the release version ( cat issue ) – Raspbian GNU/Linux 7 \n \l.

Headless + SSH + Version

I turned on the SSH server using sudo raspi-config and the advanced options.

The first thing I thought – Upgrade / Update to get the latest environment for the Raspberry Pi.  It’s a good start – always good to be up-to-date. Per the documentation, it may be necessary to run – sudo apt-get clean.

sudo apt-get upgrade
sudo apt-get update

The raspi-config is another item that may need to be updated.   The update goes out and queries for the latest raspi-config, installs and relaunches the raspi-config.

sudo raspi-config
Select Option 8 - Advanced Options
Selection Option A0 - Update 
Select Yes
raspi-config
raspi-config

Next, I looked updated the Java version.  From reading the documentation, the next versions of the Pi are going to automatically include the Java installs.

sudo apt-get update && sudo apt-get install oracle-java7-jdk
Java Installation
Java Installation

I grabbed the Pi4J project jar files. The Pi4J is an opensource project which has some great details on PINOUT and boilerplate java code to access the underlying pin readouts.  I ran some quick code to get the latest snapshot installed.

wget http://get.pi4j.com/download/pi4j-1.1-SNAPSHOT.deb
sudo dpkg -i pi4j-1.1-SNAPSHOT.deb

WGET
WGET

dpkg
dpkg

Pi4J is also installed on the Sonatype repositories and developed on GitHub.  Pi4J includes a script for managing updates.   It’s very convenient with the Apache 2.0 License.

I was ready run a sample program – Get Sample, Compile and Run.

wget https://raw.githubusercontent.com/Pi4J/pi4j/master/pi4j-example/src/main/java/ListenGpioExample.java
pi4j ListenGpioExample.java
pi4j -run ListenGpioExample
First Sample
First Sample

Eventually, I am going to get to the point where I use the diagram from Pi4j.  The future efforts are going to take some time to get to – This step was the right step in the direction I want to go.  BBQ Champion.

Raspberry Pi – Initial Thoughts

Thanks To Ada Fruit  I picked up a first version Raspberry Pi B+.   The experience brings me back to building my first computer and modifying it.

I picked up an B+ Kit from Ada Fruit (based on the fact they have awesome tutorials).  I also picked up a Motor Controller, a Bread Board to hook up peripherals, and a Touch Screen Display.  The touch screen display wasn’t actually compatible with the kit I purchased.  Lesson learned – check the Male and Female connectors for the Displays and PIN (IN/OUT) counts.

I laid out all the components on the bubble wrap, and I started assembling the components into one computer. The experience was rather like assembling a jigsaw puzzle.

Easy As Pi
Easy As Pi

I used the 4G microSD card that came with the B+ kit.  I used it to immediately configure Debian and setup SSH. I got it on the wireless using the USB dongle for wireless, and I ran the updates for aptitude update and aptitude full-upgrade.  It’s nice that it persists all these changes.

Now, that I am on the wireless, I can unplug the Raspberry Pi from the monitor, and connect to it via SSH.  It’s fantastic stuff. I am now going to work on my motor controller.

Running Debian
Running Debian