Terms 5
Definitions and Questions
ISA
The original 8- and 16-bit
expansion card standard used
in PCs. ISA cards run at a bus
speed of 8MHz. You can plug
ISA expansion cards into an
ISA slot.
Modems and sound cards
were the last ISA cards due to
their low bandwidth
requirements.
ISA is rarely found on new
motherboards nowadays, as it
has been replaced by PCI.
PCI
PCI (Peripheral Component Interconnect) is an
interconnection system between a microprocessor and
attached devices in which expansion slots are spaced
closely for high speed operation.
PCI transmits 32 bits at a time in a 124-pin connection (the
extra pins are for power supply and grounding) and 64 bits
in a 188-pin connection in an expanded implementation.
AGP
Accelerated Graphics Port (AGP) is an interface
specification that enables 3-D graphics to
display quickly on ordinary personal computers.
AGP is designed to convey 3-D images (for
example, from Web sites or CD-ROMs) much
more quickly and smoothly than is possible
today on any computer other than an expensive
graphics workstation.
It is especially useful in conjunction with gaming,
three-dimensional (3D) video, and sophisticated
scientific/engineering graphics programs.
AGP
AGP Slot
PCI Express
PCI Express - A high-speed peripheral
interconnect from Intel introduced in
2002.
Intending to eventually replace the PCI and AGP
buses entirely, PCI Express was designed to
match the higher speeds of today's CPUs. It can
accommodate Gigabit and 10 Gigabit Ethernet
and even support chip-to-chip transfers.
PCI Express
PCI Express Slot
PCI, AGP, PCI Express Q/A
Q: Please identify 3 of the following 4
pieces of hardware according to their card
type
ISA, PCI, AGP Q/A
ISA, PCI, AGP Q/A
AGP
PCI Express
PCI
ISA
IDE
IDE: Intelligent Drive Electronics or Integrated
Drive Electronics depending on who you ask. It
is an interface for mass storage devices, the
controller is integrated into the disk or the CD
ROM drive.
IDE is the standard hard drive interface for PCs.
You can connect a maximum of two hard drives
to an IDE connection or channel.
IDE hard drives are cheaper than SCSI drives,
but IDE is generally slower than SCSI and does
not support sector re-mapping.
SCSI
Pronounced “skuzzy”
SCSI: Small Computer Systems Interface is an
interface consisting of a standard port between a
computer and its peripherals that is used in
some computers.
SCSI ports allows data to be transmitted in a
“daisy chain” to up to seven devices at speeds
(32 bits at a time) higher than those possible
with serial and parallel ports.
IRQ
Interrupted Request Line is hardware lines
over which drives can send interrupt
signals to the microprocessor. When you
add a new device to a PC you sometimes
need to set its IRQ number by setting a
DIP switch. This specifies which interrupt
line the device may use.
IRQ conflicts used to be a common
problem when adding expansions boreds
but Plug-and-Play has solved most of
these.
ATAPI
Attachment Packet Interface is an
extension to EIDE that enables the
interface to support CD-ROM players and
tape drivers.
IDE / SCSI/ IRQ Q/A
Q: What is this?

A: A SCSI Terminator
USB
USB ia an acronym for Universal Serial Bus.
It is a port on a computer that allows external
devices to be connected simply and easily.
It is a protocol for transferring data to and from
digital devices.
It is known as a plug and play interface between
a computer and a low-speed peripheral, such as
a mouse, keyboard, digital camera, printer or
scanner.
Unlike devices connected via SCSI ports, USB
devices can be added to and removed from the
computer without having to reboot the computer.
Fire Wire
Firewire is the former name for High Performance Serial Bus.
It is a form of connection standard for connecting external devices to
home computers.
It is a type of cabling technology for transferring data to and from
digital devices at high speed.
Firewire card readers are typically faster than those that connect via
USB.
It allows for faster data transmission speed than SCSI and is
currently replacing SCSI connectivity.
It is well suited to applications that move large amounts of data.
It is a fast and versatile interface used to connect DV cameras to
computers.
It was invented by Apple Computer but is now commonly used with
Windows-based PCs as well.
It is also known as IEEE 1394.
iLink
Sony's name for the IEEE 1394, or FireWire,
interface. For some reason Sony decided to pick
its own name for the IEEE 1394 interface when it
is used on Sony's devices. There are no
differences between "i-Link" and IEEE 1394.
iLink is a high-speed serial digital interface
standard enabling data communication between
the digital STB and DVD Players or D-VHS
recorders.
USB, FireWire, iLink Q/A
Q: Please identify these two ports:
A: The one on the left is FireWire, the one on
the right is USB.
USB
USB
Parallel Port
The parallel port on your computer is a commonly used
interface for printers. Before USB ports became so
widely used, printers were connected through this port,
as well as scanners, external CD burners, external hard
drives, Zip drives, and network adapters.
Each byte (8 bits) of data must be sent separately to the
computer. Instead of sending each bit individually as
well, the 8 bits are all sent at the same time, which saves
a lot of time. They are sent in parallel, which is where
the name comes from.
Serial Port
The serial port is related to the parallel port. It, too, is
being eclipsed in use by USB ports, but is still in use for
some modems, printers, PDAs, and digital cameras.
Serial ports have been around for decades. They are
slower than parallel ports.
Just as the parallel port transmits data “parallel” to itself
– all 8 bits at a time, the serial port transmits data in
order, one bit at a time.
The advantage to serial ports is that they only need one
wire (instead of 8), but they take 8 times as long to send
data. Serial ports are bi-directional, which means that
data can travel in both directions on the wire.
PS/2
PS2 ports are most often used for mouse and
keyboard connections. They are electronically
similar, but the computer will not recognize them
if they aren’t on the right sockets. They function
especially well for pointer devices, like the
mouse. Mouse and keyboard devices, too, are
migrating over to USB ports.
These are bi-directional ports. They free serial
ports up for use for modems and other such
devices.
Parallel, Serial, PS/2 Port Q/A
Q: Please identify these connectors:
Parallel, Serial, PS/2 Port Q/A
PS/2
Parallel
Serial
PCMCIA
PCMCIA stands for Personal Computer Memory Card International
Association, which is an organization that consists of about 500
companies that develop a standard for PC cards. They set
standards for adding memory to portable computers, and with the
expanded standards the cards are capable to use for many other
types of devices. There are three types of cards and slots:
Type I cards are about 3.3 mm thick and are used for adding ROM
or RAM to a computer. Type I slots can only hold Type I cards.
Type II cards about up to 5.5 mm thick and are used for modem and
fax modem cards. Type II slots can hold Type I or Type II cards.
Type III cards are up to 10.5mm thick and is used for portable disk
drives. Type III slots can hold Type III cards or two Type I or Type II
cards (two of one or one of each).
Generally, you can switch PC cards without having to restart your
computer.
PCMCIA
Express Card
The Express Card was developed using PCMCIA. Some of the
rewards of using Express Cards are the cards are smaller and faster
PC Cards, it’s suitable for mobile and desktop systems, it supports
USB 2.0 and PCI Express applications, and there is a lower system
and card complexity.
There are two sizes of cards and both are smaller than a CardBus
PC Card. All Express Cards have a standard thickness of at least
5.5 mm.
The larger card (Express Card/54) supports things such as
smartcard readers, CompactFlash adapters, and 1.8 inch hard
drives.
The smaller card (Express Card/34) is appropriate for applications
such as communication, media, and general add-ins. These cards
are inserted into a universal Express Card slot.
PC Card, Express Card
PCMCIA / PC Card / Express Card Q/A
Q: Please identify this PCMCIA slot:
PCMCIA / PC Card / Express Card Q/A
A: It’s a PCMCIA Type II slot, since it can take 2
cards.