FOCUS Enhancements 3.2 - Manual (Page 166)

External Control Commands
152
Display Control (DS)
Command:
Turns the on screen status display on or off .
Format:
xDS<CR>
Response:
R<CR>
Explanation:
This command is used to call up a graphic overlay. All elements
of that overlay except the border box around the edge of the picture
are included. A value of 0 for x will turn on the graphic overlay
while a value of 1 will turn off the graphic overlay. Any other
value is considered invalid and will return an error code of NAK
without changing the state of the graphic overlay.
Examples:
0DS
Turns on the graphic overlay for the Firefly. If the graphic overlay
was already enabled on a channel at the time this command was
received, no change is made.
0@0DS
Turns off the graphic overlay. If the graphic overlay was already
off, no change is made.