Chapter 4 SCSI Commands
Overview of SCSI Command and Status Processing
DLT-S4 Interface Reference Guide
29
Behavior at Power-On
4
Depending on the interface, the DLT-S4 tape drive’s behavior at power-
on consists of the following:
• Parallel SCSI
• The drive’s SCSI lines are set to high impedance.
• The design of the drive prevents it from generating any spurious
signals on the SCSI bus during power-on.
• Following power-on self test (POST) and self initialization, the
tape drive responds to SCSI bus selections and returns
appropriate, normal responses. The drive responds to tape
motion commands with
CHECK CONDITION
status, Sense Key set
to
NOT READY
, until the tape medium is ready.
• The drive rewinds the tape to Beginning of Tape (BOT).
• The drive goes through a calibration process at power-on and
loading of media.
• Fibre Channel
• Transceivers are turned on and auto speed negotiation occurs
unless a speed jumper on the rear panel of the drive is set, in
which case the drive operates at the selected speed.
• Topology is initialized (loop, point-to-point, or fabric).
• In point-to-point mode, the drive is ready to send a FLOGI to
determine if there is a fabric present.
• In public loop mode, the drive is ready to log into the fabric.
• In private loop mode, the drive is ready to accept a login request
from a host.
• The drive rewinds the tape to Beginning of Tape (BOT).
• The drive goes through a calibration process at power-on and
loading of media.
• Following power-on self test (POST) and self initialization, the
tape drive is ready to respond to interface traffic. The drive
responds to tape motion commands with
CHECK CONDITION
status, Sense Key set to
NOT READY
, until the tape medium is
ready.