Transcript Peripheral Devices

Scanner
Speaker
Monitor
External Drive
Mouse
Keyboard
XT Keyboard
AT (Standard)
AT (Enhanced)
Ergonomic
Keyboard
Dvorak Layout
Scan code
Interprets the key
New scan code
 Keys
stick.
 User with physical limitation is currently
unable to use the standard keyboard.
 No input is sent when keys are pressed.
 Keyboard-related messages or beep codes
given during computer boot.
 Wrong characters are displayed on the screen
when user inputs information.
 Multimedia buttons not working properly.
 New keyboard won’t plug into the same port as
the old keyboard.
Mouse
Touchpad
Trackball
Encoder wheel
Click!
 Mouse
pointer jumps around on the screen.
 Cordless mouse is in use and mouse pointer is
jumping around or not moving.
 Mouse works sometimes, but not others.
 Mouse is not working.
 USB mouse is not working properly.
Data
Horizontal & vertical
deflection coils
Magnetic yoke
Electron guns
Color dots
Red
Blue
Green
Technology
Description
Shadow mask
One way to keep the beam from hitting the wrong dot is to use
a metal sheet with a tiny hole for each trio of adjacent red,
green, and blue dots. This grill is a shadow mask; it keeps stray
electrons from bleeding over into other colored dots.
Aperture grill
Other monitors use very thin vertical strips of metal to block the
stray electrons from hitting the wrong dots on the tube. These
strips form an aperture grill. Monitors using the aperture grill
may have a brighter display with a sharper image, but wires
used to stabilize the strips form very thin horizontal lines on the
screen image.
Slotted mask
This is a combination of shadow mask and aperture grill
technologies. It uses vertical slots with horizontal masks to produce
a stable image that is brighter than shadow mask.
Characteristic
Description
Resolution
The maximum number of pixels on a monitor.
Refresh rate
The number of times per second that the entire monitor is scanned
to illuminate the pixels.
Color depth
The number of bits used to store the color of a pixel.
Font
A size and style of typeface.
15 14 13 12 11
5
10 9
4
3
8
2
7
1
6
The aspect ratio of most computer monitors is 4:3
Pincushion
Barrel
Trapezoid
 No
image displayed on the monitor.
 Monitor flickers.
 Monitor is dark or power indicator light is
not lit.
 Monitor turns itself off.
 Screen is fine until a specific application
is started, then the screen goes blank,
flickers, or acts bizarrely.
 Monitor is on, but rather than displaying
an image or being black, it is white.
Cut sheet feeder
Moves bail bar
against or away
from the platten
Select Tractor or
Friction Feed
Creates images using pins
that strike an inked ribbon
Slot for font cards
Adjust printer settings
with these buttons
Adjust gap between
print head and paper
Print head
Ribbon
Manually advance
the ribbon
Sprockets with
prongs and latches fit over
holes in the edge
of the paper
Continuous sheet paper
with perforations to
create individual sheets
Paper loaded in
cut sheet feeder
Bail holding
paper against
the platten
Lever set
for cut sheet,
friction feed
Paper
Ink ribbon
Tractor
Electrical signals from
microprocessor
Coils
Print head
Pins
Electrical signals cause pins
to move out toward the ribbon
Ink cartridges
with integrated
print heads
Paper feeds straight through the same side
up from cut sheet feeder at the top to the
output tray at the lower front
Separate black and color cartridges;
color cartridge contains reservoirs for
cyan, magenta, and yellow
Ink is sprayed
onto the paper
Paper
Print head and
reservoir
Melted ink is forced out to
spray against the paper;
each droplet is about one
one-millionth of a normal drop
Print head
nozzle detail
Resistor creates heat
that vaporizes some of
the ink from the reservoir
Rollers
LocalTalk port
Type B parallel port
Type C parallel port
Output tray
Laser cartridge
Input trays
IR port
Laser
Corona wire
charging the drum
Toner supply
Fusing unit uses
heat and pressure
to adhere toner
to paper
EP drum
Paper
Corona wires
charging the paper
Printer Type
Description
Dot matrix
Forms images using a set of pins that strike an
inked ribbon.
Inkjet
Forms images by spraying ink on the paper.
Laser
Forms images on paper by using a laser beam and an
electrophotographic drum.
Solid ink
Uses ink from melted solid-ink sticks.
Dye sublimation
Uses a thermal process to transfer dye to
paper to create images.
Thermo
autochrome
Uses special paper that has cyan, magenta, and yellow layers.
Thermal wax
Uses plastic films covered with colored wax.
Application
GDI
Print driver
1
User prints
document
2
Client-side
spooler
Server-side
spooler
Calls printer
driver
3
Renders
job
4
Returns
control to
application
5
Print router
Inserts job
into print
stream
6
Which print
server?
Local print
provider
7A
8
Spools job and
locates print
processor
Print
processor
7B
Completes
rendering
Separator page
processor
7C
Inserts
separator
page
To Windows
Remote print provider
To NetWare
Port
monitor
7D
Communicates
with printer
Printer
7E
Produces
output
 Nothing
will print from any application.
 Printer doesn’t print the way the user
expects it to.
 User can’t access network printer.
 Printer prints part of a document then prints
garbage for the rest of the document.
 Horizontal
lines appear in the print so parts
of characters are missing.
 Flecks and smudges on the paper.
 Poor print quality.
 Continuous-feed paper jams.
 Poor
print quality.
 No output; paper passes through printer but
is blank.
 Fuzzy output.
 Smeared
output or output rubs off the paper.
 Low-quality image.
 Repeating horizontal lines or white spaces.
 Repeating vertical lines or white spaces.
A
clean environment prolongs the life and
usability of most equipment, including
printers.
 Relative humidity of 50 to 60 percent is good
for computer equipment.
Touch sensor
panel
USB connector