Product manual

Glossary
77 A1 69UP Rev00 G-7
Record Zero
The first record after the home address.
Reselect
The function that occurs when a target disconnects from an initiator in order to perform a time-
consuming function and, then after performing that function, reestablishes the connection.
Reserved
The term used for bits, bytes, fields, and code values that are set aside for future standardization.
S
SCSI
Small Computer System Interface.
SCSI Adapter
A circuit board used to interface the SCSI bus with an internal bus. Used in this manual to identify
the Symmetrix SCSI Adapter that interfaces the SCSI bus from the host(s) to the Symmetrix SCSI
Channel Director. Symmetrix SCSI Adapters, located in the rear card cages, have four SCSI
connectors for attaching cables from the hosts(s).
SCSI Address
The octal representation of the unique address (0-7) assigned to a SCSI device. This address would
normally be assigned and set in the SCSI device during system installation.
SCSI Device
A host computer adapter or peripheral controller or intelligent peripheral that can be attached to the
SCSI bus.
SCSI ID
The bit significant representation of the SCSI address referring to one of the signal lines DB(7-0).
Short Miss
Requested data is not in cache, but is in the process of being fetched.
Single-ended Interface
An electrical signal configuration that uses a single line for each signal and references a ground
path common to the other signal lines. The single-ended configuration is susceptible to common
mode noise and has a maximum cable length of 6 meters. See also Differential Interface.
SIO
Start I/O.
SRDF
Symmetrix Remote Data Facility. SRDF consists of the microcode and hardware required to
support Symmetrix remote mirroring.