Panasonic FP-D250 User Manual page 609

Print Server A computer and/or software to provide users or a network with access
to a central printer. The printer server acts as a buffer, holding the information to be
printed out in memory until the printer is free. It is possible to program the printer
server to print jobs in the order they arrive or to give priority to particular users who,
in effect, jump the queue. The advantages of a printer server include maximum
exploitation of expensive resources like laser printers and not having to retry if the
printer is initially busy. The print server keeps track of print jobs, allows manipulation
of printer queues, and sends print jobs to the printer.
Printer driver A program that controls printing and sets options such as print quality
and paper size for a particular printer. For example, in LAN Manager, each printer
queue has a single printer driver associated with it.
Print Spooler A separate cache of memory dedicated to accepting and sending
print data to a printer, allowing the user to run another program without interference.
Print Quality A term describing the visual impression of a printed piece. In paper,
the properties of the paper that affects its appearance and the quality of reproduction.
PAD (Packet Assembler/Disassembler) A device used in a packet switched network
to convert data to an appropriate format so that a non X.25 (non-packet switching)
device can send information over an X.25 (packet switched) network, The pad is
responsible for call set up and addressing routines.
Parallel interface An interface that can handle a group of bits transmitted at the
same time, by sending each bit over a separate wire. Probably the best known parallel
interface of all is the one developed by Centronics, a printer manufacturer, that has
36 pins and can handle a byte of data at a time. The transmission of the data is
controlled by a computer generated strobe pulse.
Parity Bit An extra bit added to a group of bits, usually to a seven-bit byte. The parity
bit can be of 0 or 1 value so that every byte will then add up to an odd or even
number, depending on whether odd or even parity is chosen. When the transmitting
device frames a character, it counts the numbers of 0s and 1s in the frame and
attaches the appropriate parity bit. The recipient counts all the 0s and 1s and compares
the total to the odd or even message contained in the parity bit. If there's a discrepancy
the recipient asks for the data to be resent.
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