Interface Specifications
Serial interface pin assignments
The serial interface connector pin assignments and a description of
the interface signals are shown in the table below. The direction of
signals is given relative to the printer.
6
DSR
IN
7
20
SG
DTR OUT
Signal Pin
Signa
1
FG
2
TXD
3
RXD
IN
4
RTS
OUT
5
CTS
I
Direction Description
This line is connected to the printer chassis.
OUT
IN
Transmits data. This pin transmits serial data
from the printer to the computer.
Received data. This pin transmits serial data from
the computer to the printer.
Request to send. This pin is held high by the
printer.
Clear to send. This pin indicates that the
computer is ready to receive data from the
printer. The printer will not proceed unless the
signal is high. Can be set high with SelecType.
Data set ready. This pin indicates that the
computer is ready to receive data from the
printer. Can be set high with SelecType.
Signal ground. This pin provides a ground for all
the signal lines.
Data terminal ready. This pin indicates whether or
not the printer is ready to receive data. If the
printer ready protocol is not selected, this pin is
always high (i.e. the printer is ready to receive
data). If printer ready protocol is selected, the
printer can accept data when the pin level is high,
and cannot accept data when the pin level is low.
When the DTR signal goes low the host computer
must stop sending data within 128 characters.
Can be set high or low with SelecType.
Technical Specifications
8-17
