Citizen CT-D101 User Manual page 29

Notes
To connect more than one printer to a single computer by USB, you must change the serial
number of the USB interface.
Use a serial cable with the connection layout shown below.
Place the interface cable so that people do not trip on it.
9-pin (female) - 9-pin (female) cable
PC
Signal Pin
RXD 2
TXD 3
DTR 4
SG 5
DSR 6
RTS 7
CTS 8
CAUTION
– 29 –
Printer
Pin Signal
2 RXD
3 TXD
4 DTR
5 SG
6 DSR
7 RTS
8 CTS