User's Manual

D-7
User's Manual
INTERFACE INFORMATION
Interface
SERIAL INTERFACE
RS-232C is the standard serial interface for data terminal equipment. The
cable connector at the printer side should be a D-subminiature Cannon or
Cinch DB-25P male connector or equivalent that conforms to EIA standards.
The table that follows shows the pin assignments commonly used by most
computers. In the table:
• “Input” denotes a signal from the computer to the printer.
• “Output” denotes a signal from the printer to the computer.
• The signal level for mark state (logical 1) is -3 V or lower; for space
state (logical 0), it is +3 V or higher.
Pin Signal Direc- Description
No. Name tion
1 FG – Frame Ground
2 TD Output Transmitted Data. This pin carries information
from the printer to the computer.
3 RD Input Received Data. This pin carries information from
the computer to the printer.
4 RTS Output Request To Send. Spaces are sent when the
printer is ready to transmit data.
5 CTS Input Clear To Send. Spaces are sent when the
computer is ready to receive data.
6 DSR Input Data Set Ready. Spaces are sent when the
computer has been powered on and is ready to
receive or transmit data.
7 SG – Signal Ground (common return)
8 CD Input Carrier Detect. Spaces are sent when the
computer allows the printer to receive data.
11 RC Output Reverse Channel. This signal is used instead of
the DTR signal in the RC protocol. Spaces are
sent when the printer is ready to receive or
transmit data.
20 DTR Output Data Terminal Ready. Spaces are sent when the
printer has been powered on and is ready to
receive or transmit data.