Kyocera FS-680 - Manual (Page 127)

Serial (RS-232C/RS-422A) Interface (Option)
C-10
Overview of Signals (RS-422A)
FG – Frame Ground – (Pin 1)
This pin is connected directly to the printer frame.
SG – Signal Ground – (Pin 7)
All signals can transmit between the printer and the host computer to send each signals with a signal
ground.
RDB – Receive Data – (Pin 18)
RDA – Receive Data Inverted – (Pin 3)
These pins carry asynchronous data sent from the computer to the printer. (differential input)
SDB – Send Data – (Pin 10)
SDA – Send Data Inverted – (Pin 9)
These pins carry asynchronous data sent from the printer to the computer. (differential output)
RS-422A interface voltage levels
The interface signal voltage levels conform with the EIA RS-422A standard. The differential voltage
varies from 200 mV to 6V.
SERIAL Connector
The connector marked "IOIOI " (RS-232C/RS-422A) on the rear panel is a DB-25S connector. Use a
DB-25P connector (or equivalent) for the connector on the cable.