Seagate Ultra 320 - Manual (Page 20)

6 Parallel SCSI Interface Product Manual, Rev. A
double transition (DT)—The latching of data on both the assertion edge and the negated edge of the REQ or
ACK signals.
driver—The circuitry used to control the state of the bus.
enabled task state—The state of a task that may complete at any time. Alternatively, the state of a task that is
waiting to receive the next command in a series of linked commands.
ended command—A command that has completed or aborted.
exception condition—Any event that causes a SCSI device to enter an auto contingent allegiance or contin-
gent allegiance condition.
faulted initiator—The initiator to which a Command Terminated or CHECK CONDITION status was returned.
faulted I_T nexus: The I_T nexus on which a CHECK CONDITION status was returned that resulted in the
establishment of an ACA. The faulted I_T nexus condition is cleared when the ACA condition is cleared.
faulted task set: A task set that contains a faulting task. The faulted task set condition is cleared when the
ACA condition resulting from the CHECK CONDITION status is cleared.
faulting command: A command that completed with a status of CHECK CONDITION that resulted in the
establishment of an ACA.
faulting task: A task that has completed with a status of CHECK CONDITION that resulted in the establish-
ment of an ACA.
function complete—A logical unit response indicating that a task management function has finished. The
actual events comprising this response are protocol specific.
hard reset—a SCSI target port response to a reset event or a SCSI target port Reset in which the target per-
forms the operations described in Section 7.6.7.
implementation—The physical realization of an object.
implementation-specific—A requirement or feature that is defined in a SCSI standard but whose implemen-
tation may be specified by the system integrator or vendor.
implementation option—An option whose actualization within an implementation is at the discretion of the
implementor.
indication—The second step in a four-step confirmed service reply to a request.
information unit transfer—Parallel transfers that transfer data, status, commands, task attributes, task man-
agement information, acrid, and nexus information using only SPI information units.
initial connection—The result of a physical connect. It exists from the assertion of the BSY signal in a
SELECTION PHASE until the next BUS FREE PHASE or the next QAS REQUEST message.
initiator—A SCSI device containing application clients which originate device service and task management
requests to be processed by a SCSI target port SCSI device.
interconnect—The electrical media (including connectors and passive loads) used to connect the TERM-
PWR, terminators, and SCSI devices in a SCSI bus.
interconnect subsystem—One or more physical interconnects which appear as a single path for the transfer
of information between SCSI devices in a domain.
intersymbol interference (ISI)—The effect of adjacent symbols on the symbol currently being received.
in transit—Information that has been sent to a remote object but not yet received.