Fujitsu DL7400 Manuale Utente

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. 

 

1 FG 

− 

Frame Ground 

2 TD  Output 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.