Epson C82310 - Manual (Page 11)

The tables below describe the interface conditions that
can be selected using jumpers. In all cases, ON means
you connect the jumper (cover both terminals), while
OFF means you disconnection of the jumper.
Table 3. Jumper settings
Jumper Function Factory setting
J1 Fixed (See Note)
J2 Fixed (See Note)
J3 Fixed (See Note)
J4 Fixed (See Note)
JG ON: Connect chassis ground to signal OFF
ground
Note
Jl,J2,J3, and J4 jumpers are connected at the factory; do
not change these setting.
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