• We recently switched our forum platform. If you experience any issues please email support@crystalfontz.com

Controlling the Backlight on 631


New member
I have been unsuccessfully trying to programmatically turn the backlight on and off on a 631 display. I believe that the message type is a 14 with a data length of 1. I have been sending the following:
(all values decimal)
14 1 0 15 207 to turn off and
14 1 100 5 239 to turn on.

Neither message works. I have also been "playing" with wintest.exe trying to understand this command.

Can anyone help with this problem? There appears to be some question as to what actual data is being sent. For example when using the wintest.exe, I must send "\000" to turn the backlight off. "0", "\0" and "\00" do not work.
Looking for additional LCD resources? Check out our LCD blog for the latest developments in LCD technology.