RadiSys EPC-5A, Справочное руководство по аппаратному и программному обеспечению

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Glossary
G-7
Interrupt Request (IRQ): In ISAbus 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 or KByte): Approximately one thousand bytes. 2
10
= 1024 bytes
exactly.

L

Logical Address: The memory-mapped location of a segment after application of the
address offset to the physical address.
Logical Block Addressing (LBA): A method the system BIOS uses to reference hard
disk data as logical blocks, with each block having a specific location on the
disk. LBA differs from the CHS reference method in that the BIOS requires
no information relating to disk cylinders, heads, or sectors. LBA can be used
only on hard disk drives designed to support it.

M - N

Megabyte (MB or MByte): Approximately one million bytes. 2
20
= 1,048,576 bytes
exactly.