Oki 182 Handbook page 168

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Interface
LPI
Parallel Interface
Parity
PROM
The connection between two pieces of equipment,
such as between a computer and a printer. The
two basic types of interface are parallel and serial.
The word is loosely used to mean either the
method of connection or the actual hardware used
to connect equipment, including the circuits that
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control communication. As a verb, it usually
means the act of making the connection.
Lines Per Inch: a measure of line spacing. When
the line spacing is 6 LPI, the distance between the
bottom of one line of print and the bottom of the
next is 1/6 inch.
An interface in which the eight bits comprised by
a byte of data are transmitted simultaneously over
eight separate wires.
A method of checking for data transmission errors
used in some serial interfaces. The computer adds
a bit (the "parity bit") to each byte of data so the
total number of 1 s is either always even ("even
parity") or always odd ("odd parity"). The printer
checks each incoming byte plus parity bit to make
sure the parity is correct. If the parity is not cor­
rect, the data has not been sent (or received) prop­
erly. The printer will signal when it detects a
"parity error."
Programmable Read-Only Memory: ROM that can
be programmed, but only with special equipment,
so for most people PROM and ROM are the
same. Some MICROLINE options consist of a set
of PROMs to replace those in the standard printer.
The new PROMs tell the printer to interpret con­
trol codes differently.
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