Fujitsu DL3100 User Manual page 192

FUJITSU DL3100
D-8
Signal description
The signal electrical level of the interface pin is defined
as follow:
1 is low level (Mark) -25V~-3V
0 is high level(Space) +3V~+25V
DTR protocol(RS-232C)
Pin2(receiving data)
Receiving the serial data sent from the host with this
line, so when no data is sent, the host must be set to
MARK.
Pin4 DTR(Data terminal)
When the printer ready for receiving data，the signal is
SPACE(high level), when the printer did not receive
data, the signal is MARK(low level).
Pin 5 SGND(Signal ground lines)
Signal ground
XON/XOFF (RS-232C)
Pin2 RXD (Receiving data)
Receiving the serial data sent from the host with this
line, so when no data is sent, the host must be set to
MARK.
Pin3 TXD(Sending data)
Receiving the serial data sent from the host with this
line, so when no data is sent, the host must be set to
MARK.
Pin4 DTR(Data terminal)
When connecting to the printer, the signal sent from
printer is SPACE (high level).
Pin 5 SGND(Signal ground lines)
Signal ground
Pin 7 RTS(Request to send )
When connecting to the printer, the signal sent from
printer is SPACE (high level).
User's Manual