B-2 Appendix B—Serial Interface
abbreviations, and pin assignments. The direction of the arrow indicates
whether the signal is an input or output of the device.
Pin assignments are specified for 25-pin D-type connectors. The RS-232-
C standard does not specify pin assignments for serial communication on
9-pin connectors.
Only nine of the 25 RS-232-C signals are commonly used in serial
connections. These nine are listed in the table on Page B-4.
Serial Port
Connector
JB0-BL
RS-422-A serial interface is optional. RS-422-A serial connectivity
involves differential drivers and receivers for extended computer-to-printer
distances, depending on the baud. RS-422-A signals are not
implemented on the standard printer.