Epson TM-T20II Technical Reference Manual page 39

Pass-through connection
This printer is connected to the host computer through the serial interface via the customer
display (DM-D).
AC Adapter
+ AC cable
Serial cable
Connecting the serial interface (RS-232) cable
Be sure to turn off the power supply for both the printer and host computer before
connecting the cables.
WARNING
1
Insert the serial cable connector firmly into the serial interface
connector.
2
When using connectors equipped with screws, tighten them to secure
the connectors firmly.
3
Connect the other end of the serial cable to the host computer.
Extended
power cable
Serial cable
DM-D
TM-T20II
Chapter 2 Setup
DK cable
Cash drawer
2
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