Interfaces
8-29
Serial Interface
The serial interface allows data to flow back and forth between the computer and the
printer. However, the serial interface transfers data at a slower rate than the parallel
interface.
If a serial connector is required, you may be able to install an RS-232C Serial Interface
Card, an External Serial Adapter, or an RS-232C Serial/Parallel 1284-C Interface
Card. Refer to your printer user documentation for more information.
The External Serial Adapter supports two serial interface standards: RS-232C and
RS-422. The RS-422 serial interface provides more protection from electrical noise
than RS-232.
Use RS-232C serial interface if the printer is more than 3.04 m (10 ft) from the
computer but less than 15.24 m (50 ft) away. (You can also use a 6.1 m (20 ft) Lexmark
cable to connect a printer and a computer located up to 20 feet apart.)
Use RS-422 if your computer is more than 15.24 m (50 ft) away from the printer. You
may need to purchase an RS-422 adapter and software for your computer to run
RS-422. Refer to your computer documentation for more information. You also need
to purchase a custom cable for the serial interface, because serial RS-422 interface
pinouts are usually unique to each computer.
When using the serial interface, your printer has the following differences from the
serial interface on some other printers:
•
The printer returns XON/XOFF with 2 stop bits in all cases.
•
The printer does not support DTR inversion.
Using the RS-232C Serial Interface
This section describes how to use the RS-232C serial interface. If you are using
RS-422, see “Using the RS-422 Serial Interface” on page 8-39.
How to Connect the RS-232C Serial Interface
Use Lexmark serial cable P/N 1038693 (15.24 m or 50 ft) to connect the serial
interface.
