A Printer Is a
Printer Is a Printer …
Computer users
get rather animated and emotional when their printers don't work. No matter
what type of printer is involved, at some point it will all of a sudden just
stop working. The true definition of a nanosecond is the length of time it
takes the user to dial your number after the printer has not immediately spewed
forth a document in perfect form. A significant portion of the exam is devoted
to printers, their function, problems, and care. Although most of the questions
are about laser printers, be ready for questions on dot matrix and inkjet
(bubble jet) printers.
The
most commonly used connectors used to connect printers directly to a PC are
l 25-pin DB (data bus) female connector: The
parallel port on the back of a PC is a 25-pin female connector into which the
male connector counterpart on the printer cable is connected. Most computers
today have only one LPT port, and it's usually mounted either on the motherboard
or an expansion card.
l 36-pin Centronics: This common connector is used at the printer end of the
connecting cable. The PC end of the cable is a 25-pin male connector, as
described in the previous bullet. The Centronics connector is also the standard
connector for the HP-IB (Hewlett Packard Interface Bus). This general style of
connector has become known as the Centronics connector because Centronics
Corporation produced a large share of the printers used for the earliest PCs.
Ampenol produced the original design. Other types of Centronics connectors are used
on the PC, such as the 50-pin SCSI, but the 36-pin is the one used with
printers.
l USB: Some of the latest printers now feature a USB connection in addition
to the standard parallel connector. But, if the printer you're working on is a
bit older, it can still be connected to the PC via a USB port using a USB to a
parallel adapter cable. This cable has a Centronics connector on the printer
end and a USB connector on the PC end. Why would you connect your printer via
the USB port? You may want to free up your parallel port for another use, such
as a scanner or a Zip drive, or you may want to connect the printer to a USB
hub.
l IR (infrared) or IrDA (Infrared Data Association):
Some adapters, such as the one made by Extended Systems ( www.extendedsystems.com
), can be used to connect a parallel printer to a PC through its
IrDA connection, which frees the parallel port on the PC for other uses. A
number of handheld-size printers designed for use with notebooks and PDAs that
interface with an IrDA connection are also available.
A
Plethora of Printers
You
can connect many different types of printers to a PC. If you are one of the
lucky few who always have the latest and greatest hardware, you probably have a
distorted view of the kinds of computers that most users actually have--not the
latest and greatest. Many dot-matrix, inkjet, bubble jet, and even some noisy,
old daisy-wheel printers are still in use. Not everyone has a laser printer.
Remember
The printers that are listed in the objectives of the A+ Core
Hardware exam (the ones you are supposed to know) are:
l Dot-matrix: These printers create characters by
forming a group of hard-wire pins into the pattern of the letter, number, or
special character and then striking the entire pin group through a ribbon, forming
the character on paper.
l Inkjet or bubble jet: Inkjet printers are probably
the most popular printer type in use. They produce a better-quality print
without the noise of the dot-matrix printer and at a lower price than a laser
printer. Inkjet printers produce an image by heating ink into steam and then
"jetting" it onto the paper.
l Laser: These printers use a complex printing process to produce very
high-quality documents.
Laser
printers are becoming more common on the desktop, especially with prices continuing
to decline.
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