RPi and Java Embedded GPIO: It all begins with hardware

Posted by hinkmond on Oracle Blogs See other posts from Oracle Blogs or by hinkmond
Published on Tue, 30 Oct 2012 23:58:53 +0000 Indexed on 2012/10/31 5:13 UTC
Read the original article Hit count: 223

Filed under:

/Java Embedded

So, you want to connect low-level peripherals (like blinky-blinky LEDs) to your Raspberry Pi and use Java Embedded technology to program it, do you? You sick foolish masochist. No, just kidding! That's awesome!

You've come to the right place. I'll step you though it.

And, as with many embedded projects, it all begins with hardware. So, the first thing to do is to get acquainted with the GPIO header on your RPi board. A "header" just means a thingy with a bunch of pins sticking up from it where you can connect wires. See the the red box outline in the photo.

Now, there are many ways to connect to that header outlined by the red box in the photo (which the RPi folks call the P1 header). One way is to use a breakout kit like the one at Adafruit. But, we'll just use jumper wires in this example.

So, to connect jumper wires to the header you need a map of where to connect which wire. That's why you need to study the pinout in the photo. That's your map for connecting wires.

But, as with many things in life, it's not all that simple. RPi folks have made things a little tricky. There are two revisions of the P1 header pinout. One for older boards (RPi boards made before Sep 2012), which is called Revision 1. And, one for those fancy 512MB boards that were shipped after Sep 2012, which is called Revision 2. So, first make sure which board you have: either you have the Model A or B with 128MB or 256MB built before Sep 2012 and you need to look at the pinout for Rev. 1, or you have the Model B with 512MB and need to look at Rev. 2.

That's all you need for now.

More to come...

Hinkmond

Related posts about /Java Embedded

Tomcat 6: Access Control Exception?

as seen on Server Fault - Search for 'Server Fault'
I'm trying to setup a tomcat6 server, and I'm trying to match another setup someone else established. However, my deployment (default Ubuntu install) uses a policy.d/ directory structure, and the established server just uses a catalina.policy file. I've tried setting every entry in policy.d to match… >>> More
failing to establish connection between Postgres db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am using Postgres and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When I try to connect it gives "ClassNotFoundException". Here is what I get when I try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
failing to establish connection between postgre db and gwt

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, For i am using postgre and gwt 2.0 for one of my applications. I am facing problem connecting to the database. When i try to connect it gives "ClassNotFoundException". Here is what i get when i try to connect to database: java.lang.ClassNotFoundException: org.postgresql.Driver at java.net… >>> More
Problem in creation MDB Queue connection at Jboss StartUp

as seen on Stack Overflow - Search for 'Stack Overflow'
I am not able to create a Queue connection in JBOSS4.2.3GA Version & Java1.5, as I am using MDB as per the below details. I am putting this MDB in a jar file(named utsJar.jar) and copied it in deploy folder of JBOSS, In the test env. this MDB works well but in another env. [ env settings and… >>> More
Migration and deployement problems JBoss 4.2.2.GA to JBoss 6.0.0.M2

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I'm trying to migrate an application running on JBoss 4.2.2.GA to JBoss 6.0.0.M2 I give you some log to explain my problem : boot.log : 2010-03-16 09:59:29,406 ERROR [org.jboss.system.server.profileservice.ProfileServiceBootstrap] (Thread-2) Failed to load profile: Summary of incomplete deployments… >>> More

Developer IT