Oki Microline 520 Service Handbook page 258

Serial Cable Information
The information in this section will help you make a serial cable to connect between the printer
and computer.
Refer to the computer documentation to determine the cable requirements on the computers end.
The printer has the following cable requirements.
• Shielded, RS-232C cable
• UL and CSA approved
No more than 50 feet long
•
Cannon DB-25P plug (or equivalent) with 25 pins
•
Cannon DB-C2-J9 (or equivalent) connector shell
•
Serial Interface Signal Requirements
Pin Signal
1 Protective Ground
2 Transmit Data
3 Receive Data
4 Request to Send
5 Not Used
6 Data Set Ready
7 Signal Ground
8 Not Used
to
10
11 Supervisory Send Data
12 Not Used
to
19
20 Data Terminal Ready
21 Not Used
to
25
Failure Analysis
Symbol Direction
PG Ground
TD From Printer
RD To Printer
RTS From Printer
DSR To Printer
SG Ground
SSD From Printer
DTR From Printer
4 - 50
Description
Connected to the printer frame
Serial data transmitted to the system
Serial data received by the printer
Always set to low (mark)
Indicates that data can be sent
Ground
Indicates that the printer is not ready to
receive data
Indicates that the printer is not ready to
receive data
Microline 520/521 Service Handbook
P/N 59257803