Reference
PC/AT-compatible
computers
A “PC/AT-compatible computer” is a
computer that is compatible with PC/AT
computers made by U.S.-based IBM
Corporation.
The “IBM PC/AT” computer specification was released in 1984. Many hardware manufacturers produced computers according to this specification, and
it is now a global standard for computers.
(1)Serial interface
A “serial interface” is an interface that transfers data one bit at a time.
It uses few signal lines and is not prone to signal variation, making it suitable for long-distance transmission.
The standards for serial interfaces are summarized below.
Standard
RS-232C
An interface used to connect a computer unit to a modem or mouse.
They are standard and built into PC/AT-compatible computers.
USB
An interface used to connect various types of peripherals such as a
keyboard, mouse, printer, or display. A USB hub can be used to
connect up to 127 peripherals. While the power is on, peripherals
can be connected or removed (hot plugging), and power can also
be supplied to them over a cable.
Data transmission speeds range from 1.5Mbps for low-speed mode
(USB 1.1) to 480Mbps for high-speed mode (USB 2.0).
IEEE1394
An interface used to connect devices such as a digital video camera
or DVD-RAM. Up to 63 peripherals can be connected. It enables hot
plugging and power to be supplied. Also referred to as “FireWire”
and “i.Link.”
Reference
Bus power method
“Bus power method” is a method of
supplying power to USB equipment
over a USB cable. USB equipment that
does not need an AC adapter or power
cord is operable simply by connecting a
USB cable and receiving power via
USB.
Characteristics
RS-232C
D-sub 25-pin
D-sub 9-pin
Reference
bps
“bps” refers to the amount of data that
can be transferred in one second.
Abbreviation for “bits per second.”
USB
IEEE1394
USB connection example
USB hub
Printer
CD-ROM
drive
USB hub
Scanner
MO
drive
Digital
camera
Up to 127 devices including USB hubs can be connected
* Printers and other peripherals can also be directly connected to the
USB port of the computer unit.
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