Monitoring: Video Input

All Digital View controllers enable users to remotely monitor whether there is a valid video input signal. This may be important for many display system applications but most obviously it is important for digital signage displays.

There are various ways to implement this but a good place to start is to test it. First connect an LCD using a Digital View LCD controller with a valid video source, ensure it is all operating properly, ie there is an image on the display. Then connect a PC to the LCD controller using RS-232 (see the controller manual for details). On the PC use a RS-232 terminal application such as Accessport (free download on the web).

In the RS-232 software select hex input mode and type the RS-232 command C9 to query the LCD controller for a valid video source. The system should respond with one of the following:

  • C9 50 31: This is a hex value and translates to 50=‘P’ 31=‘1’ where ‘P’ ‘1′ means there is a valid signal on the Display Port source.
  • C9 30 30: This is a hex value and translates to 30=‘0′ 30=‘0’ where ‘0’ ‘0′ means no video signal on the input port.

The full command structure as shown in the controller manual is:
“0”,”0” : no video source / disabled
“A”,”1” = VGA
“F”,”1” = DVI
“H,”1” = HDMI 1
“H,”2” = HDMI 2
“H,”3” = HDMI 3
“E,”1” = HD-SDI
“P,”1” = DP

Hex translation is done via an ASCII table, we provide a table in the LCD controller manual but you can also find many on the web.

In Practice

In practice entering commands is somewhat laborious so it is better to incorporate the command into an application that may run automatically and send data as a report to a dashboard or as a query within a GUI based software application. We provide some RS-232 applications for free down load on the Digital View software page.

If you need assistance with setting up display monitoring using a Digital View LCD controller let us know.

Active Notification

A custom option is to have active notification whereby the LCD controller board will send a notification over RS-232 if the video status changes. This is not enabled as a default due to the potentially unwanted messages it might create with some systems. For more details on options like this please contact us.