User`s guide

Chapter 2 Installing Internal Tape Drives
Reviewing Drive Default Settings
DDS-4/DAT 72 User’s Guide 17
Parity Checking 2
Jumper Pins 9–10:
Pins 9-10 shunted: Enable parity checking (default)
Pins 9-10 open: Disable parity checking
By default, parity checking is enabled on the internal tape drive. To
disable parity checking, remove the jumper from pins 9 and 10.
Terminator Power 2
Jumper Pins 11–12:
Pins 11-12 shunted: Enable terminator power
Pins 11-12 open: Disable terminator power (default)
By default, terminator power is disabled on the internal tape drive. To
enable terminator power, place a jumper across pins 11 and 12.
Data
Compression
2
Settings:
Switch 1 ON = Enable hardware data compression (default)
Switch 1 OFF = Disable hardware data compression
Switch 2 OFF = Recognize SCSI data compression commands (default)
Switch 2 ON = Ignore SCSI data compression commands
The internal tape drive provides two switches for controlling data
compression.
Switch 1 determines whether hardware data compression is enabled or
disabled. By default, switch 1 is set to ON, enabling hardware data
compression. To disable hardware data compression, set switch 1 to the
OFF position.
Note: If you disable parity checking, the drive still generates a parity
bit.
Note: If you enable terminator power, be careful not to short the
TERMPWR signal to ground (for example, by attaching the
SCSI cable upside down). If a short occurs, terminator power to
the bus is interrupted. After the short is removed, a fuse in the
drive is automatically reset, restoring terminator power.