Siemens SIMATIC PANEL PC 877 - Manual (Page 104)

Operation
10.3 Device with key panel
SIMATIC Panel PC 877
10-16
Operating instructions, Release 07/2006, A5E00877780-01
10.3.4 Using the integrated mouse
The position on which you press the middle round button of the integrated mouse determines
the direction in which the cursor moves. The amount of pressure determines the speed of
the cursor.
Alternatively to using the integrated mouse you can also connect an external mouse to the
front USB port.
Figure 10-11 Integrated mouse