Mita DP-2800 Instruction Handbook Manual page 212

Serial (RS-232C/RS-422A) Interface
Overview of Signals (RS-422A)
C-12
Interface Signals
The pins in the printer's RS-422A interface connector carry the signals listed in Table C.3 .
Table C.3. RS-422A Signal Pin Assignments
Pin In/out
1 –
3 In
7 –
9 Out
10 Out
11 –
18 In
FG – Frame Ground – (Pin 1)
This pin is connected directly to the printer frame.
RDA – Receive Data Inverted – (Pin 3)
RDB – Receive Data – (Pin 18)
These pins carry asynchronous data sent from the computer to the printer. (differential input)
SG – Signal Ground – (Pin 7)
All signals can transmit between the printer and the host computer to send each signals with a signal
ground.
+5V DC (Pin 11)
This line is connected to the printer's +5V DC line (+5V ±0.5V, 250 mA [Serial and Parallel total]
maximum, fused).
Signal Description
FG Frame ground
RDA Receive data Inverted
SG Signal ground
SDA Send data Inverted
SDB Send data
– +5V DC
RDB Receive data