Spectec SDV-841/842 - Manual (Page 17)

Cursor Key and Edge Panning
In addition to using the onscreen control, the view window can also be panned
by pressing a cursor key or by moving the pen to one of the edges of the
physical display. If the pen is held at an edge, the view window will pan
continuously in very small increments until it reaches the edge of the virtual
display.
To use the cursor keys for panning you must check the Pan with Arrow Keys
property as described in Modifying Configuration Properties .