Avago Technologies LSI53C120 - Manual (Page 58)

B-6 Glossary
Peripheral
device A device that can be attached to an SCSI bus. Typical peripheral devices
are disk drives, tape drives, printers, CD ROMs, or communications units.
Phase One of the eight states to which the SCSI bus can be set. During each
phase, different communication tasks can be performed.
Plug and Play
(PnP) Plug and Play is a specification that frees users from locating and setting
ID and IRQ switches and jumpers. PnP permits a card to be configured
automatically after installation.
Port A connection into a bus. The SCSI bus allows eight ports.
Priority The ranking of the devices on the bus during arbitration.
Protocol A convention for data transmission that encompasses timing control,
formatting, and data representation.
Receiver The circuitry that receives electrical signals on a line.
Reconnect The function that occurs when a target reselects an initiator to continue
an operation after a disconnect.
Release The act of allowing the cable terminators to bias the signal to the false
state (by placing the driver in the high impedance condition).
REQ/ Request – Driven by a target, indicates a request for an SCSI data-
transfer handshake. This signal is received by the initiator.
Reselect A target can disconnect from an initiator in order to perform a time-
consuming function, such as a disk seek. After performing the operation,
the target can “reselect” the initiator.
RESET Reset – Clears all internal registers when active. It does not assert the
SCSI RST/ signal and therefore does not reset the SCSI bus.
RST Reset – Indicates an SCSI Bus reset condition.
SCSI Address The octal representation of the unique address (0-7) assigned to an
SCSI device. This address is normally assigned and set in the SCSI
device during system installation.
SCSI ID
(Identification)
or SCSI Device
ID The bit-significant representation of the SCSI address referring to one of
the signal lines DB0/ through DB7/.