Printronix L5520 - Manual (Page 221)

RS-422 Serial Interface
221
The serial data transfer baud rate is selectable from the control
panel. The input format consists of a single start bit, 7 or 8 data bits,
and one or two stop bits. The operator can set the number of data
bits from the control panel. The data bits are interpreted with the
least significant bit first. The operator can also set parity checking
via the control panel. The printer interface uses a first-in/first-out
buffer with the size selectable from the control panel. The
asynchronous interface accepts data as it is provided by the host
computer.
The maximum cable length from the host computer to the printer is
4000 feet.
The maximum baud rate supported by the RS-422 serial interface
is 256 KB.