2
Description of the signals used
2.1
Reference (GND)
Computer and printer earth in common.
2.2
DSR (Data Set Ready)
in voltage levels transmission or
DSR+ and DSR-
in loop transmission.
A printer input. This signal activates the V24 mode.
A symbol appears on the screen when the DSR signal is active
on S4 or on S4 Plus.
2.3
DTR (Data Terminal Ready)
in voltage levels transmission
A printer output. The signal is active as soon as the printer is ready to dialog.
2.4
RTS (Request To Send)
A printer output. The signal is active at every character sequence sent by the printer.
2.5
CTS (Clear To Send)
A printer input. The signal instructs the printer to send.
2.6
TXD (Transmit Data)
in voltage levels transmission or
TTY OUT+ and TTY OUT-
in loop transmission.
A printer output. Data transmission.
2.7
RXD (Receive Data)
in voltage levels transmission or
TTY IN+ and TTY IN-
in loop transmission.
A printer input. Data reception.
C
General
A13862 Version E
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