LSI 20860 - Manual (Page 24)

A-2 Glossary of Terms and Abbreviations
Host Adapter A circuit board or integrated circuit that provides a SCSI bus connection
to the computer system.
Internal SCSI
Device A SCSI device installed inside the computer cabinet. These devices are
connected in a continuous chain using an unshielded ribbon cable.
IRQ Interrupt Request Channel. A path through which a device can get the
immediate attention of the computer’s CPU. The PCI bus assigns an IRQ
path for each SCSI host adapter.
Local Bus A way to connect peripherals directly to computer memory. It bypasses
the slower ISA and EISA buses. PCI is a local bus standard.
Mainboard A large circuit board that holds RAM, ROM, the microprocessor, custom
integrated circuits, and other components that make a computer work. It
also has expansion slots for host adapters and other expansion boards.
Main Memory The part of a computer’s memory which is directly accessible by the CPU
(usually synonymous with RAM).
Motherboard See Mainboard. In some countries, the term Motherboard is not
appropriate.
Operating
System (OS) A program that organizes the internal activities of the computer and its
peripheral devices. An operating system performs basic tasks such as
moving data to and from devices, and managing information in memory.
It also provides the user interface.
PCI Peripheral Component Interconnect. A local bus specification that allows
connection of peripherals directly to computer memory. It bypasses the
slower ISA and EISA buses.
Peripheral
Devices A piece of hardware (such as a video monitor, disk drive, printer, or
CD-ROM) used with a computer and under the computer’s control. SCSI
peripherals are controlled through a SCSI host adapter.
Pin-1
Orientation The alignment of pin 1 on a SCSI cable connector and the pin-1 position
on the SCSI connector into which it is inserted. External SCSI cables are
always keyed to ensure proper alignment. Internal SCSI ribbon cables
are sometimes not keyed, although they may have a colored strip
indicating pin 1.
Port Address Also Port Number. The address through which commands are sent to a
host adapter board. This address is assigned by the PCI bus.