Oki Microline 3390 User Manual page 292

RS-232C Serial Interface
In a serial interface the bits of one byte are transmitted consecutive-
ly. Additional lines control the flow of data. This type of connection
is often used with networks. Using a serial interface large distances
can be covered without any disturbances.
When using a serial interface, correct wiring as well as correct set-
ting of the interface parameters (configuration) is of importance.
For most applications the default settings are sufficient. Occasional-
ly you might have to change some parameters. Never change val-
ues which are not described in your computer or network manual.
The position of jumper plug SP1 should never be changed. If the
interface's control program is stored in the microprocessor, SP1 has
to connect the two pins close to the interface connection (Position
B). If the control program is stored in the EPROM, SP1 has to con-
nect the two pins pointing away from the connection (Position A).
Jumper SP1
Appendix D: Interface Data
Interface boards may vary in
design.
D-5