Specifications

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Glossary
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Header: A mechanical pin and sleeve style connector on a circuit board. The header
may exist in either a male or female configuration. For example, a male header has a
number and pattern of pins which corresponds to the number and pattern of sleeves on
a female header plug.
Hexadecimal (h): A base 16 numbering system using numeric symbols 0 through 9
plus alpha characters A, B, C, D, E, and F as the 16 digit symbols. Digits A through F
are equivalent to the decimal values 10 through 15.
 I 
Industry Standard Architecture (ISA): A popular microcomputer expansion bus
architecture standard. The ISA standard originated with the IBM PC when the system
bus was expanded to accept peripheral cards.
Input/Output (I/O): The communication interface between system components and
between the system and connected peripherals.
Integrated Drive Electronics (IDE): A hard disk drive/controller interface standard.
IDE drives contain the controller circuitry at the drive itself, as compared to the
location of this circuitry on the computer motherboard in non-IDE systems. IDE
drives typically connect to the system bus with a simple adapter card containing a
minimum of on-board logic.
Interrupt Request (INT): A software-generated interrupt request.
Interrupt Request (IRQ): In ISA bus systems, a microprocessor input from the
control bus used by I/O devices to interrupt execution of the current program and
cause the microprocessor to jump to a special program called the interrupt service
routine. The microprocessor executes this special program, which normally involves
servicing the interrupting device. When the interrupt service routine is completed, the
microprocessor resumes execution of the program it was working on before the
interruption occurred.
Interrupt Service Routine (ISR): A program executed by the microprocessor upon
receipt of an interrupt request from an I/O device and containing instructions for
servicing of the device.
 J 
Jumper: A set of male connector pins on a circuit board over which can be placed
coupling devices to electrically connect pairs of the pins. By electrically connecting
different pins, a circuit board can be configured to function in predictable ways to suit
different applications.
 K 
Kilobyte (KB): One thousand bytes; 2
10
= 1024 bytes, to be exact..
 L 
Liquid Crystal Display (LCD): A device containing a series or matrix of liquid
crystal diodes. Each diode consists of a sandwich of transparent electrodes, between