Epson Endeavor Setup Manual page 23

To connect a mouse to the built-in mouse port, plug the
connector into the port marked MOUSE, as shown below.
Caution
Although the connectors and ports for the mouse and
keyboard are physically identical, they cannot be used
interchangeably. Be sure to plug the mouse connector into
the MOUSE port.
If your system has not already been configured, you may need
to install a mouse driver. See your mouse manual for
instructions.
1-12
Setting Up Your System
MOUSE