Viper 60s Theory Of Operation And Maintenance Manual page 169

VIPER SCSI 60, 125 & 150 THEORY OF OPERATION AND MAINTENANCE
LUN.
See Logical Unit Number.
MODE.
Definition of parameters that control the method in which the Viper reads or writes
data.
MSB.
Most significant byte or most significant bit.
PARAMETER.
An operational element, such as the number of buffers used, whose value varies
depending on system applications.
POINTERS.
SCSI provides two sets of three pointers, current and saved, to help maintain
communication.
QIC.
Quarter-Inch-Cartridge standard.
RECONNECT.
The action of a target selecting an initiator to resume an operation after a
disconnect has occurred.
SCSI.
Small Computer System Interface. A standard for communication between microcom-
puters and peripherals that allows multiple peripherals.-
SCSI DEVICE.
Any host computer or peripheral device that can be connected to a SCSI bus.
SCSI ID.
A bitwise representation of the SCSI Address.
SCSI ADDRESS.
A unique address value (range 0-7) that identifies a device connected to a SCSI
bus. The Viper 150 SCSI address is set by jumpers prior to installation and connection.
SERPENTINE.
The winding, logical pattern that results when the streaming tape drive records
data on the tape.
SOFT ERROR.
Is a repeated attempt by the tape drive firmware to read or write data on the tape
to correct a problem area on the tape. Soft error is not a real error, but a reliability feature.
No data is lost.
STATUS BYTE.
One byte of information returned from a target to an initiator upon completion
of a command.
STREAMING.
Tape recording method designed for continuous tape motion with continuous
recording of data on the tape.
TAPE POSITION.
Where the tape is stopped with respect to the tape drive recording heads.
TARGET.
Any SCSI device that performs operations requested by an initiator.
UNRECOVERABLE ERROR.
An error that is not correctable. Usually the result of a soft error
condition that cannot be corrected by retries. Data is lost.
UNDEr:RUN. ,,\
condition that occurs when data is transferred faster than it can be processed.
The underrun tally is the number of times that the tape drive streaming action stops
during a backup or a restore operation.
VENDOR-UNIQUE.
Any bits, fields or command values that are not defined by the ANSI X3.131
standard.
WRITE-PROTECTED.
Cannot be written (recorded) on.
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