Pi4J Version 1.2 Release

Version 1.2 of the Pi4J Library is finally released!

The long overdue release of version 1.2 is finally here!  It's been over two year since the 1.1 release and there have been about 136 new commits to the 1.2 release which include many enhancements, optimizations, bug fixes and additional platform support for Odroid, BananaPi, BananaPro, and OrangePi boards as well as adding support for the new RaspberryPi models introduced during this time..

Pi4J Version 1.2 is also available in Maven Central.  <<View in Maven Central>>

Notable Version 1.2 Changes:

• Removed support for statically compiled wiringPi library (for Raspberry Pi).
• Added support for Raspberry Pi 3B+
• Added support for Raspberry Pi Zero W
• Added support for Raspberry Pi Compute Module 3
• Updated to Java 8 (enhancement #203)
• Updated build dependencies/plugins to latest versions.
• Removed unsupported sub-projects (pi4j-temp, pi4j-service).
• Added SPI mode support for Odroid, BananaPi, BananaPro, and OrangePi platforms.
• Added experimental support for OrangePi platform.
• Added experimental support for Synovoip BPI (BananaPi) platform.
• Added experimental support for NanoPi platform.
• Fixed #438: ArrayIndex Out of Bounds when pin address address is >= 100
• Fixed #278: wiringPiSetup*: You must only call this once per program run.
• Fixed #294; added java runtime and compiler check to pi4j helper script
• Fixed #291; W1Device name contains "\n"
• Fixed #275; LCDExample.java doesn't work in release
• Fixed #276; RaspiBcmPin pins not firing pin state change events
• Fixed #198; Problems with data from HMC5883L class
• Fixed #351; Pi4J packages excluded in OSGI manifest ImportPackage declaration
• Fixed #360; Serial.setBreak(TRUE|FALSE) is printing debug lines to stdout
• Fixed #355; ButtonBase Executor Service should be closed on GpioController.shutdown()
• Fixed #356; SystemInfoProvider CPU temperature was divided by 1000 on OrangePi
• Fixed #272; SerialDataEvent should not fire when event.length() == 0
• Fixed #361; SerialFactory isShutdown() state not getting updated on new instance

Special Thanks:

Thank You to all the Pi4J users, contributors, testers, and tinkerers for all your help and support to continue making Pi4J the go-to library for Java access to the Raspberry Pi's hardware interfaces. 

Pi4J Related Links: 

• Pi4J Website
• Pi4J Github Repository
• Pi4J Google Groups/Forum
• Pi4J JavaDoc

(click to enlarge)The Pibrella add-on board serves as a simple and easy platform to get started with and learn about inputs and outputs on your Raspberry Pi.  

Pibrella is an excellent development tool for both hobbyist and students to learn about programmatic interfacing with inputs and outputs to monitor and control things in the real world. 

For beginners, three LED lights and a momentary button are provided directly on the board so you can get started playing with the input signals for the momentary button and output signals for controlling the LED lights without having to wire any circuits yourself.  

One you are ready to sense (inputs) or control (outputs) other external devices you can use the 4 generic inputs and 4 generic outputs at the bottom of the Pibrella board via the 2 8-pin header connectors.  (Note, breadboard/prototyping jump wires fit perfectly into these header blocks.) 

<<< BUY PIBRELLA ON AMAZON $22.99 with Prime Shipping >>>

More details and instructions for getting started can be found at: http://pibrella.com/

Pi4J + Pibrella

The Pibrella documentation primarily includes information about programming the Pibrella using Python.  However, we at Pi4J recognizing the Pibrella device as an excellent tool for beginners did not want to leave Java programmers out of the party.  So, we have added native support for the Pibrella board directly into Pi4J.  

Sources

The Pibrella devices interfaces can be found here:
https://github.com/Pi4J/pi4j/tree/develop/pi4j-device/src/main/java/com/pi4j/device/pibrella

An example program demonstrating the usage of the Pibrella device interface can be found here:
https://github.com/Pi4J/pi4j/blob/develop/pi4j-example/src/main/java/PiBrellaExample.java 

Example

Below is a sample program to help you get started using the Pibrella board in your Java program.

Board Layout

<<< BUY PIBRELLA ON AMAZON $22.99 with Prime Shipping >>>

Thanks to all that attended yesterday's #Devoxx "Let's Get Physical" talk on #Raspberry_Pi & #Pi4J #java #iot #raspi pic.twitter.com/3dyngd6jKY

— Robert Savage (@savageautomate) November 13, 2014

Thanks to all that attended today's #Devoxx talk on #Java 8 #Raspberry_Pi & #Pi4J with @steveonjava @JavaFXpert & me. pic.twitter.com/mbz5dH11vW

— Robert Savage (@savageautomate) November 11, 2014

For anyone that may have missed it, check out this article in May/June issue of Java Magazine featuring me and the Pi4J project.
http://www.oraclejavamagazine-digital.com/javamagazine_open/20140506/?pg=18&pm=1&u1=friend

	Look inside >
PI4J PROJECT

My Raspberry Pi just got a whole lot *sweeter*.

While attending JavaOne this year, Oracle announced that the Raspberry Pi foundation would soon start shipping the Oracle JDK/JVM (Java) baked into the Raspbian distribution.

Here was the official announcement on raspberrypi.org:
http://www.raspberrypi.org/archives/4920

And a day later new images were posted for download that include Oracle Java SE fully "baked in".
http://www.raspberrypi.org/archives/4959 

You can download the latest Raspian image that includes Oracle Java SE 7 here:
http://www.raspberrypi.org/downloads 

Here is a slide (photo) from the JavaOne Community Keynote where this was announced.

Photo by @yarasenger

Its a real treat to flash and boot up a fresh Raspberry Pi (Raspbian) image and Java be there without requiring additional steps to install it.

Java SE 8 - Developer Preview

If you prefer to install the JDK8 developer preview/early access version, please see this page:
Install Oracle Java SE8 (Milestone 8) Developer Preview (JDK)

Thank You

Thank You JavaOne attendees for joining my session today on I/O programming with Java using Pi4J on the Raspberry Pi.  Thank You Oracle for accepting my talk and providing the opportunity to for me to spead the embedded/IOT message.

I do plan on posting additional in-depth articles to this blog that cover how I built the demo system and the access control solution.  In the meantime,  I have posted a couple of photos from the session as well as the slides and links to the source code below.

Photos

Slides / Presentation

Source Code

All of the source code examples used in the presentation can be found here on GitHub:
https://github.com/savagehomeautomation/pi4j-javaone-demos

Here is a recent interview with Steven Chin (steveonjava) on the NightHacking Tour for my upcoming JavaOne session.

Session: CON7968 - Let’s Get Physical: I/O Programming with Java on the Raspberry Pi with Pi4J
When: Wednesday, Sep 25, 11:30 AM - 12:30 PM
Where: Hotel Nikko - Monterey I/II

Video streaming by Ustream

We will be reviewing into the fundamentals of programming with Pi4J and jumping into some real world demos of how you can use Pi4J and the Raspberry Pi platform to automate things in your life!    

Session: CON7968 - Let’s Get Physical: I/O Programming with Java on the Raspberry Pi with Pi4J
When: Wednesday, Sep 25, 11:30 AM - 12:30 PM
Where: Hotel Nikko - Monterey I/II

Abstract:

Overview

Announcing the release of Version 0.0.4 of the Pi4J project!

Version 0.0.4 is the first "official" release of the Pi4J project.  Development snapshot builds have been available since September but now an official release is available complete with an installer and a number of sample projects to help you get started.    

Project Summary

This project is intended to provide a bridge between the native hardware and Java for full access to the Raspberry Pi in with a Java-friendly object-oriented approach.  Pi4J provides a set of advanced features that make working with the Raspberry Pi an easy to implement and more convenient experience for Java developers.   

>> View original project announcement.

Pi4J Project Website

The Pi4J website content has been updated with instructions and examples for 0.0.4.

• http://www.pi4j.com

Follow @Pi4J on Twitter

The Pi4J project now posts announcements on Twitter.  
Follow us to get the latest Pi4J release notices and other Pi4J news.

Follow @pi4j  

Pi4J Google Groups - Forums

The Pi4J project has started a Pi4J Google Groups forum for community discussions on Pi4J project development.

• https://groups.google.com/forum/#!forum/pi4j  

Raspberry Pi Java Forums

For general questions and support try posting to the Java topic on the Raspberry Pi community forums:

• Raspberry Pi > Programming > Java 

New Installation Package

Version 0.0.4 introduces a new installer package that makes it easy to install the Pi4J libraries and examples on a Raspbian / Debian OS distribution.  See the link below for instructions on downloading and installing Pi4J.

• http://pi4j.com/install.html

Maven Central

With the release of 0.0.4, the Pi4J project artifacts are now available on Maven Central:

• http://search.maven.org/#search|ga|1|pi4j

Release Notes - Version 0.0.4

2012-12-16 :: 0.0.4

• Added support for building a Pi4J .deb installer package for Debian/Raspian Linux distribution. (BETA)
• Modified NetworkInfo static methods to permit empty array return values when a network property cannot be obtained.https://github.com/Pi4J/pi4j/issues/3
• Fixed issue in newer Raspberry Pi 512mb firmware where Pi4J was not compiled against latest wiringPi library and thus not detecting the hardware properly. https://github.com/Pi4J/pi4j/issues/3
• Fixed defect where Pi4J library prevented consuming program from exiting properly. https://github.com/Pi4J/pi4j/issues/4 | https://github.com/Pi4J/pi4j/issues/6
• Added support for MCP23008 GPIO Provider using I2C bus.
• Added support for MCP23017 GPIO Provider using I2C bus.
• Modified build script to support concurrent soft-float and hard-float native library builds
• Modified build script to include pulling wiringPi sources and compiling when building native library
• Added power controller device interface, base impl, and reference impl
• Added GpioController.provisionXXXPin methods that allow name to be optional
• Relocated project downloads location to google code site; github deprecated downloads.
• Added Google Groups discussion forum to project docs.
• Added getTag() and setTag() to GpioPin interface and impl.
• Added TemperatureConversion utility.
• Added optional blocking argument to GpioPin pulse method to support blocking pulse invocations

>> Click here to see the full: Release Notes

Getting Started

To get started using the Pi4J library, please see the Usage page and review each of the examples to explore the functionality provided by the Pi4j library.

Overview

> sudo apt-get install openjdk-7-jdk

> wget https://github.com/downloads/savagehomeautomation/raspi-sspc/raspi-sspc-1.0.0.jar

> wget https://github.com/downloads/Pi4J/pi4j/pi4j-core-0.0.3-SNAPSHOT.jar

> sudo java -classpath classes:./'*' SSPC

> sudo java -classpath classes:./'*' SSPC -longitude=-73.985538 -latitude=40.748362

While working on The Pi4J Project, I found the need to have some type of GPIO prototyping board to quickly visualize the state of GPIO pins and control the state of GPIO pins.   I purchased a handful of electronics parts and set out to build my GPIO testing board.

The picture below is the final result of building this test board:

Design Goals

My design goals included:

• Support 7 GPIO pins.
• Small/compact footprint.
• Connect to Raspberry Pi via ribbon cable.
• Support for momentary and fix on/off switches.
• Display GPIO state using LEDs.
• Captive screw terminals for connecting GPIO pins to external devices.
• Order the GPIO test IO hardware based on the Pi4J/WiringPi pin numbering scheme. 

Supplies / Parts

I purchased most of the parts used in this project on eBay.  

• 1 @ 26P ribbon cable (1 meter or less)
• 2 @ 26P female IDC connectors (press-fit)
• 1 @ 26P box header IDC male sockets (right angle or straight)
• 7 @ 1.5 VDC red LED
• 7 @ 220 ohm resistors
• 7 @ 0.3A DC 50V Mini Vertical Slide Switch SPDT 3 Pin PCB
• 7 @ 6mm x 5mm Panel PCB Momentary Tactile Tact Push Button Switch DIP (normally open)
• 4 @ 3pin Block Terminal screw connector 5mm pitch
• Solder (lead-free)
• Scrap wire

Tools Needed

• Wire snips (Hakko CHP170 Micro Cutter, 16AWG Clean Cut)
• Wire strippers (Paladin Tools 1118 GripP 20 Wire Stripper/Cutter, 30-20 AWG)
• Solder Iron (Weller WLC100 40-Watt Soldering Station)
• Digital Multimeter w/ Continuity Testing (Extech MN35 Digital Mini MultiMeter)

Logic

• When a GPIO pin is configured as an OUTPUT pin and its state is set to HIGH, the corresponding LED should be ON. (+3.3 VDC is delivered to the anode lead of the LED)
• When a GPIO pin is configured as an OUTPUT pin and its state is set to LOW, the corresponding LED should be OFF. (0 VDC is delivered to the anode lead of the LED)
• When a GPIO pin is configured as an INPUT pin and the correspondingly momentary switch is depressed or the toggle switch is in the ON position, the LED should be ON and +3.3 VDC is delivered to the GPIO pin on the Pi.
• When a GPIO pin is configured as an INPUT pin and the correspondingly momentary switch is not depressed and the toggle switch is in the OFF position, the LED should be OFF and 0 VDC is delivered to the GPIO pin on the Pi.

Wiring Diagram

The following illustration depicts the wiring schematic used to create this GPIO test board.

(NOTE:  The GPIO pin numbering is based on the Pi4J/WiringPi GPIO pin numbering scheme.  But of course you can apply whatever GPIO pin numbering scheme to meet your needs.)

Click diagram to enlarge.

Photos

Click any photo to enlarge.

Videos

This is a simple demonstration video of this GPIO test board in action with a simple Java program cycling states on the 7 GPIO output pins.

Announcing the Pi4J project!

This project is intended to provide a bridge between the native hardware and Java for full access to the Raspberry Pi in with a Java-friendly object-oriented approach.  Pi4J is an open source project developed by professional software engineers.  In addition to the basic raw hardware access functionality, this project also attempts to provide a set of advanced features that make working with the Raspberry Pi an easy to implement and more convenient experience for Java developers.   

Project Website

• http://www.pi4j.com

Source Repository

• https://github.com/Pi4J/pi4j/

Basic Features

• Export & unexport GPIO pins
• Configure GPIO pin direction
• Configure GPIO pin edge detection
• Control/write/set GPIO pin states
• Read GPIO pin states
• Send & receive data via RS232 serial communication

Advanced Features

• Pulse GPIO pin states
• Listen for GPIO pin state changes (interrupt-based events; not polling)
• Automatically set GPIO states on program termination (GPIO shutdown)
• Triggers for automation based on pin state changes
• Access system information and network information from the Raspberry Pi
• Wrapper classes for direct access to WiringPi Library from Java

Getting Started

To get started using the Pi4J library, please see the Usage page and review each of the examples below to explore the functionality provided by the Pi4j library.

• Control GPIO
• Listen for GPIO Events
• Shutdown GPIO
• Trigger GPIO on Events
• Serial Communication
• System/Network Information

Simple Usage Example

Below is a simple example demonstrating controlling a single GPIO pin state.
(Please visit this page for a more in-depth view of this example: Control GPIO Example) 

public static void main(String[] args) throws InterruptedException
{
    System.out.println("<--Pi4J--> GPIO Control Example ... started.");
        
    // create gpio controller
    Gpio gpio = GpioFactory.createInstance();
        
    // provision gpio pin #01 as an output pin and turn on
    GpioPin pin = gpio.provisionOuputPin(Pin.GPIO_01, "MyLED", 
                                                PinState.HIGH);
    System.out.println("--> GPIO state should be: ON");
        
    Thread.sleep(5000);
        
    // turn off gpio pin #01
    pin.low();
    System.out.println("--> GPIO state should be: OFF");

    Thread.sleep(5000);

    // toggle the current state of gpio pin #01 (should turn on)
    pin.toggle();
    System.out.println("--> GPIO state should be: ON");

    Thread.sleep(5000);

    // toggle the current state of gpio pin #01  (should turn off)
    pin.toggle();
    System.out.println("--> GPIO state should be: OFF");
        
    Thread.sleep(5000);

    // turn on gpio pin #01 for 1 second and then off
    System.out.println("--> GPIO state should be: ON for only 1 second");
    pin.pulse(1000);
}

Stay tuned ... more articles to come on using the Pi4J library.