Tuesday, April 11, 2017

QuickStart: Programming Java On Your Raspberry PI

The Raspberry PI comes with Java already installed when you install Rasbian however the 2 Programming IDE that it comes with will not let you open your java files for editing rather you have to use an alternative.

There are a few choices in doing this. You can install Eclipse on your computer and then deploy and/or debug from your computer connected remotely to your Raspberry PI.  This is nice in some ways because you have the power of the full IDE however as you are working remotely, so if you want to tweek stuff right on the Raspberry PI you are constantly flipping from SSH or VNC to your local computer and back.

Alternatively, you can install a lightweight IDE right on the Raspberry PI.  This allows you to work locally, edit files locally. No switching back and forth.  Here is a list of some lightweight IDE:

  1. Dr. Java is a lightweight development environment for writing Java programs. It is designed primarily for students, providing an intuitive interface and the ability to interactively evaluate Java code. It also includes powerful features for more advanced users.  
  2. Geany is a lightweight ide as well. You can install it using this the following:

    sumo apt-get install geany
  3. BlueJ is one of the IDE already installed however when you try to open the files you MUST choose Open Non BlueJ

  4. Algoid is a light weight IDE as well. 
There are lots of other ways to work with Java on your Raspberry PI. If you have other ways let me know and I will add them here.  Email me at chris.williams@readwatchcreate.com and follow me on twitter @BerryPIChris

Monday, April 10, 2017

Thursday, April 6, 2017

QuickStart: Installing Ubuntu On Raspberry PI From Windows

The Raspberry PI offers support for a large number of Operating Systems. This article lists all the operating systems supported by Raspberry PI.  I started off with Raspbian, which installs by default.  I went on to try Windows 10 IOT Core for Raspberry PI 3, following that I tried Ubuntu.  This article details how to install Ubuntu by copying it to your MicroSD from a computer running Windows.
  • To start make sure your computer has a slot to insert the MicroSD card.
  • An Ubuntu SSO account is required to create the first user on an Ubuntu Core installation.
    so login or register.
  • Once logged in you can retrieve the Ubuntu SSH Keys. You will need these later when you load Ubuntu for the first time.
  • If you don't have a program to unzip .tz file then download 7Zip.
  • Next download the Ubuntu Mate from the Raspberry PI tab
  • Use 7Zip or whaterver program you use to unzip .tz to unzip the Ubuntu image .tz file
  • Next download and install Windows Disk Imager. Make sure you choose Create Desktop Shortcut as it will save you time later. You can always delete it when done
  • When completed choose to run Windows Disk Imager
  • Click the icon beside Image File to select the Ubuntu image

  • Use the device dropdown to choose your Micro SD card.
  • Click on Write and it will copy the image to the card.
  • After the copy completes successfully you are ready to install.
  • Insert the Micro SD card into your Raspberry PI and plug in the power.
  • You can follow the Ubuntu installation steps
My next step is installing .NET Core on Ubuntu. I will keep you posted.

If you are having trouble installing Ubuntu on Raspberry PI or have other questions, let me know. My email is chris.williams@readwatchcreate.com. Please follow me on twitter at @BerryPIChris

QuickStart: Install Remote Desktop On Raspbian

Once you get the basic install done, you probably don't want to use the HDMI and would rather just access the device remotely from your laptop or computer.  You can use SSH or if you want to see the full desktop would want to use Remote Desktop or more accurately VNC.

This article explains how to install Real VNC on Raspberry PI.

However, there are a couple places that we ran into issues:

  1. Enable VNC is Missing
    • Once your run the sudo command to install the server and client. You still may not see the setting to Enable VNC. If this is the case then you may need to enter the terminal using CTRL-ALT-F1 and then enter the command: sudo shutdown -r 0
    • After the reboot is finished, then look for the option again.
    • If you still cannot find the option from the menu -> preferences enter the terminal window again.
    • Type: sudo raspi-config
    • You will likely find the option here and can enable it.  Once you enable it here it will show up under preferences as well.
    • I installed Raspbian and VNC multiple times and sometimes it worked using the article and other times I needed to follow the above tips. I am not sure why but if you run into it too you have a solution.
  2. When connecting from a Client you will need the IP of your Raspberry PI. If you are plugged into the internet using the network adapter and a cable the article explains well how to find the IP however if you connect via WI_FI, an easy way to find the IP is to hover over the network icon in the top right corner of your desktop.
If you are still having trouble with the setting up VNC or have other questions, let me know. My email address is chris.williams@readwatchcreate.com. Please follow me on twitter at @BerryPIChris

QuickStart: Use 35mm Audio Jack Instead Of HDMI Audio On Raspbian

In some cases, using the HDMI Audio is ideal especially if you are connecting it to a display but in most cases you will not be using the Raspberry PI this way and will likely want to switch to using the Audio Jack or later even use other connectors such as a USB or Bluetooth Speaker.  This article will show you how to change it to the 35mm Audio Jack but you can use this as a pattern for later.

  • Click CTRL-ALT F1 to open the Terminal Window.
  • Type: sudo raspi-config
  • Choose option 8 - Advanced Options
  • Choose option 6 - Audio
  • Change from 0 to 2 using the arrows or your mouse and press enter.
  • Use the arrows to move to finished and press enter.
  • Reboot using: sudo shutdown -r 0
  • When it boots back up open the browser and navigate to YouTube and try playing a video. If the audio plays through your speaker you are all set.  

If this does not work, then you will have to use this workaround.

  • Click CTRL-ALT-F1 to open the Terminal Window
  • Type: sudo leafpad /boot/config.txt
  • When the editor comes up look for the line hdmi_drive=
  • If the number after the equal sign is not 2 change it to 2
  • Reboot using: sudo shutdown -r 0
  • When it boots back up open the browser and navigate to YouTube and try playing a video. If the audio plays through your speaker you are all set. 
If you are still having trouble with the 35mm Speaker or have other questions, let me know. My email address is chris.williams@readwatchcreate.com. Please follow me on twitter at @BerryPIChris

QuickStart: Setting Up Your Raspberry PI

This QuickStart will help you through the initial set up of your Raspberry PI 3. After getting it set up, take a look at our other QuickStarts that will help you do things like configure the Raspberry PI 3 to use the Audio Jack rather than HDMI for audio, Set up Remote Desktop, Enable Bluetooth and pair with a Bluetooth Headset and more.

The Raspberry PI 3 comes with a good set of instructions to get you started however, the first struggle I had and from Googling others have as well is getting the "Demonic" plug removed from the Power Adapter and your proper plug attached.  It is actually quite simple once someone points it out.  In the center of the plug is a T shape.  Press on that and slide.  Now slide the proper one on until it clicks.

Before plugging in, make sure the MicroSD card is inserted. It should go in easy, if not then you have it upside down.  Once you have it in, you can put the Raspberry PI in its inclosure with the SD card down first. If you do this it should slip into the case easily.  Next make sure all your peripherals such as USB keyboard, USB mouse, speakers, microphones, HDMI cable are all plugged in then plug in the power.

Once you power on it will automatically detect the keyboard and mouse and start the set up of the Raspberry OS.  The wizard is pretty straight forward getting you set up.

If you run into problems getting your Raspberry PI 3 set up or if you have other questions, let me know.  My email address is chris.williams@readwatchcreate.com.  Please follow me on twitter at @BerryPIChris