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HARDWARE DESCRIPTION
1. I/F board connector: EIA standard 25-pin D-SUB female
connector.
2. For signal description and pin assignment, refer to the
table below:
Table 9. Signal Description and Pin Assignment
Pin No. Signal Name Direction*
Description
1
Protective
Ground
-
Chassis ground
2
Transmitted
Data (TXD)
Out
Transmitted serial data
3
Received
Data (RXD)
In
Received serial data
4
Request to
Send (RTS)
Out
This signal is always at the
positive EIA level.
7
Signal
Ground
In
Return path for data and control
signals.
11
Reverse
Channel
(=2nd RTS)
Out
This signal is at the positive EIA
level when the printer is ready to
accept data entry and at the
negative EIA level when the
printer is not ready to accept data
entry. Operator can invert the
polarity of this signal with
jumper J2.
20
Data
Terminal
Ready (DTR)
Out