Friday, January 02, 2015

Getting Yamaha Disklavier Piano and DKVBrowser and Virtual PRC to work with Mac's Yosemite System

With every Mac system update, I have to test not only old programs or applications, but also some other devices and equipment to make sure they still function.

The DKVBrowser application I use to edit songs, create playlists, and control my disklavier from my laptop seemed to have a problem after installing Yosemite 10.10.  But, luckily someone posted a solution on the yahoo forum.  Basically, the application needed the Java SE 6.0 runtime module installed on my Mac.

Download of Java can be found here:

After downloading this version (which includes the correct SE 6.0 runtime module), I installed it on my Mac laptop.  The java module can be accessed from the Systems Preferences.  There are some settings that may need to be changed to have another desktop application called Virtual PRC to run properly on your Mac.
Figure 1

After installing the java runtime, DKVBrowser made an excellent attempt to connect to my piano.  Due to the fact that the IP address for my piano changes everytime I lose power or unplug it while away, the IP address had to be corrected in the DKVBrowser settings and tested for connection.   See DKVBrowser application preferences window  (figure 2).

Figure 2

In the past I have been able to type in the DKV##### number for the IP address and usually the IP address is determined automatically.  I then selected test.  The piano was still not found. This time I had to actually find the IP address to put in the edit field.  (It may also be possible that this problem happened due to the fact that my piano had also been disconnected from the airport express box near the piano.) Anyway, I was able to find the IP address eventually and DKVBrowser ran successfully -- my piano is functioning -- playing my favorite playlist.

Next on the schedule was a test of the Virtual PRC java script that puts a virtual remote controller on my Mac screen to use to control the piano - like the real one that comes with the piano.

Figure 3
If you are having problems getting Virtual PRC to run correctly after the Yosemite install:

1) Make sure your piano is connected to the internet.  My disklavier is physically connected to an Apple Express box that is near the piano.

2) Place any previous 'prcstart.php' or 'prcstart.php.jnlp' file you have used into your trash can on your Mac.

3) Click on the DKV##### icon under 'Shared' column on left of the Finder window.  Double click on the 'DNA' folder on the right-hand side of the Finder window. Double click on Virtualprc.html file or open in a browser like Firefox.  (Note: I use Firefox to run this file as I have previously had problems with Safari and Chrome working with this file.)
4) You will need to enter a username (root) and password (prcstart).  Follow the steps below for setting up and downloading a new prcstart.php file for your desktop:
Figure 4

5) After clicking on Save, a file should be downloaded to your Mac. The name of the file should be prcstart.php.jnlp -- if not -- then add the extension .jnlp to filename -- if you see only a file named 'prcstart.php'

 6) If you double click on that file, it should run the virtual PRC (see Figure 3 above).

7) If you get some error message about security blocking the app, then you will need to change the settings in the Java control panel.   This Java control panel can be accessed from Systems Preferences (under Apple icon in menu bar).  Open the Java control panel by clicking on the Java icon in the Systems Preferences panel.  See Figure 1 above.

8) Select “Security” tab from top of panel.   From here you will be able to allow for reduced security and run this java prcstart.php.jnlp file successfully.

Figure 5  

You can add in the IP address for your piano into the Exception Site List edit field.

Figure 6

Or, you can change the level of security to medium.  This will still display a security warning before any such files are run, but you can choose to ignore the security message and run anyway. 

Figure 7

 I chose to adjust the Security Level to medium as my IP address changes when I unplug from power or have an outage.  All works fine now with Yosemite System update.

Update notes for El Capitan are in the comments below (click on comments).  Please check second comment for info on correct Java 8 Version that is needed to get Virtual PRC to work with El Capitan System for Mac.  


Granny Joan said...

After installation of El Capitan, I have not been able to get Virtual PRC to work with my Mac laptop and Disklavier Mark IV

Granny Joan said...

George from pianobench in the disklavier yahoo group forum posted a solution to getting the Virtual PRC to work with El Capitan. Thanks George.

His post:

"I am able to run the Virtual PRC in El Capitan on my Mac by downgrading Java to Java 8 Update 25. Given all of the security issues surrounding Java, especially older versions of Java, I am not advising anyone to do this downgrade. However, if you want to know how it is done, here are the instructions:

1) Verify your version of Java.
To determine your version of Java, select System Preferences from the Apple men. Then click the Java icon to bring up the Java Preference Pane.

Click the Update tab to see what version of Java you have.

2) If your version of Java is earlier than Java 8 Update 25, do not use the update feature of your Java Control Panel because it will update to a later version of Java. Instead, download and install Java SE Runtime Environment 8u25 from this location:

3) If your version of Java is later than Java 8 Update 25, uninstall Java and then follow the instructions in Step 2. Instructions for uninstalling Java may be found here:

4) When your computer gives you messages to update Java or block Java, ignore them.

5) In your Finder, locate your Disklavier, which will show up as a computer on your network with a name that starts with dkv. Open the Disklavier, locate the DNA folder, and double-click VirtualPRC.html.

6) This will open a page in your web browser. Log in with the following username and password (unless you have changed them):


7) Click the Start button. This action will download a file called prcstart.php.jnlp. Locate the file and put it somewhere for future use. Then, double-click the file. This action will launch the actual PRC Java application from the Disklavier’s hard drive.

Next time you want to run the Virtual PRC, locate and double-click prcstart.php.jnlp."