There are two possible resolution settings for Interact Applications.
MOST 5 and 6 inch displays are Quarter VGA (320x240) but there have been some part numbers over the years that were 6 inch but VGA (640x480) resolution.
Units 8 inches and larger displays are all 640x480 resolution.
You can change from 8 to 10 or from 10 to 15 or 15 to 8 inch units and the application fills the screen since all of the displays are 640x480 regardless of physical dimensions.
The 6 inch units had both so knowing which one you have is critical. We require the full part number of the old unit so we can tell you the correct replacement.
Starts with Resolution Replaced By Alternate
P11-xxxxx 320x240 P1306QT-Qx PA206Q-13x
P12-3xxxx 320x240 P1306QT-Qx PA206Q-13x
P12-4xxxx 640x480 P1306VT-Qx PA206V-13x
NOTE: Alternate Replacement using PA2 requires mod to hole size in panel. Not drop in.
Check user guides for cutout dimensions.
These are basically MSDOS PCs and they have a FIXED resolution so there is no way to change resolution on the units.
Picking the wrong replacement will result in screens that look like the images below:
320x240 application running on 640x480 display
640x480 application running on a 320x240 display.