Epson LQ-1500 Service Manual page 75

3.2.2.3 Pin assignment of interface connector
A. CN1 : .This connector communicates CN1 of the UXMCL board
Refer to 2.3.1.
B. CN2: Future specification
C. CN3: This connector communicates with the Host Computer.
(1 ) Number of pins: 25 pin cannon type
Notes:
1. "Direction" refers to the direction of signal flow as viewed from the printer,
2. All signals except TTY-TXD and TTY-RXD are based on EIA RS-232C level.
Table 3.13 Pin assignment (CN3 of IURS)
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