Creating this application is a snap using several of the built-in features of the DVM. To implement this functionality, we are going to create and load the following files onto the DVM’s flash card.
- VID00001.MPG – This is the actual MPEG2 video file that will loop each day
- PLY00010.LST – This file contains the commands needed to start playback and enable the video output at the beginning of each day. (Startup playlist)
- PLY00011.LST – This file contains the commands needed to stop playback and disable the video output at the end of each day.(Shutdown playlist)
- SCHEDULE.SCL – This schedule file tells the DVM what time to launch the Startup playlist, as well as what time to launch the Shutdown playlist
Now that we know what we need to do, let’s make it happen.
If you plan to use the real-time scheduler on your Alcorn McBride product, the first thing you should do is set the time and date to ensure their accuracy. This can be done with the help of a program called AMI Terminal, which is a free software download from Alcorn McBride’s website.
AMI Terminal is a software tool that is designed to provide easy communication with Alcorn McBride products over serial and/or Ethernet. This graphical interface will allow you to control playback and configure the product (including time and date).
To set the time and date of your Alcorn McBride product using AMI Terminal, please follow these steps:
- Launch AMI Terminal and configure it to communicate with your product.
- Select the Date/Time control page for the product.
- Select the ‘Set’ option, and then click the Time and Date buttons.
- Verify that the product responds with an R<0D>.
Now it is time to create the actual schedule that the DVM will use to start and stop playback each day. Alcorn McBride provides a helpful utility for creating these schedules called Schedule Builder.
Before we launch Schedule Builder, let’s review what we want to accomplish with this schedule:
- We want to launch Playlist #10 at 8:00AM every day
- We want to launch Playlist #11 at 9:00PM every day
Now, let’s use the following step-by-step instructions to create a schedule that will do this:
- Open Schedule Builder and select the DVM-7400
- The Add/Edit Event window will automatically pop up expecting you to insert the first scheduled event. Select ‘Play Clip’ from the list of available events.
- Below the event, select the option to play the clip ‘By Number’ and insert the number 10 in the given field.
- In the Start Date/Time field, select 8:00 AM. The date is unimportant as long as it is the current date or it is a date in the past.
- Now, check the ‘Repeat’ box and specify that you want this event to Repeat every 1 Day.
- In the comment field, type in the message "Trigger the Startup Playlist at 8AM each day"
- Click the OK button to add the event to the schedule
- Click the New Event button at the top and repeat this procedure to create a daily event that will trigger playlist 11 at 9:00PM each day.
- Save this file as SCHEDULE.SCL to the DVM’s flash card.
Creating the Playlists
This application requires 2 playlists.
- Playlist #10 – This playlist must Unmute the video output, and then tell the DVM to play and loop a video file.
- Playlist #11 – This playlist must Mute the video output (forcing the output to be black) and then stop the video file from looping.
We’re going to create these playlists using Playlist Builder. To do so, follow these steps:
- Launch Playlist Builder and select the DVM-7400
- Create a new command, and select ‘Unmute’ from the command list.
- Use the parameters to specify that you want to Unmute the Video, and then click Ok to add the command.
- Create another new command, and select ‘Search Play and Loop Clip’.
- Select the ‘By Number’ parameter, and enter in the number 1 (this number represents the number of the MPEG file we want to play).
- Click Ok to add this command to the playlist.
- Save this playlist to the DVM’s flash card as PLY00010.LST
- Follow the same procedure to create another new playlist.
- Add a ‘Mute Video’ command to this new playlist
- The next event should be a ‘Stop’ command
- Once you have added these two commands, save the playlist to the DVM’s flash card as PLY00011.LST.
Now, the system is ready to operate as planned. When the DVM powers up, it loads the schedule into memory. At exactly 8AM, the schedule will launch playlist #10 causing the video output to un-blank the screen and loop the manager’s video. The video will continue to loop until playlist #11 is launched by the scheduler at 9PM. This playlist then mutes the video output to black, and commands the DVM to stop playback. At 8AM the next day (and every day), this process repeats.
Thanks to the Scheduler, the DVM-7400 is automatically playing video based on the time of day. This is just a simple example where every day is the same, but the scheduling capabilities at your disposal are practically endless. If you spend just a few minutes playing with Schedule builder, you will quickly see the flexibility you have to accomplish your goal.
As for the Playlist feature, it allows the DVM-7400 to perform a whole list of commands from a simple trigger source (i.e. Scheduler, Serial, Parallel, etc.). This example just uses Play, Stop, and Mute commands, but any command within the machine’s capabilities can be added to these playlists. For example, with the addition of a simple playlist entry the DVM could send a serial command to a plasma display to turn it on and off to prolong display life.