User's Guide

SCSI Interface Description Page 21
State or Phase Description
Command Phase
If the drive detects a parity error while the host is
transferring a CDB, the drive
• Terminates the transfer.
• Switches the host to the Status Phase and sends a
Check Condition.
• Switches the host to the Message In Phase and sends a
Command Complete.
• Sets the Sense Key = B and ASC/ASCQ = 47-00 (SCSI-
2 only).
Data In Phase
If the host detects a parity error while data is being
transferred from the drive and asserts ATN, the drive
• Terminates the transfer of data.
• Switches the host to the Message Out Phase.
• Waits for the host to send an 05 (Host Detected Error).
• Switches the host to the Status Phase and sends a
Check Condition.
• Switches the host to the Message In Phase and sends a
Command Complete.
• Sets the Sense Key = B and ASC/ASCQ = 48-00 (SCSI-
2 only).
Data Out Phase
If the drive detects a parity error while the host is
transferring data, the drive
• Terminates the transfer of data.
• Switches the host to the Status Phase and sends a
Check Condition.
• Switches the host to the Message In Phase and sends
Command Complete.
• Sets the Sense Key = B and ASC/ASCQ = 47-00 (SCSI-
2 only).
Status Phase
If the host is in the Status phase and detects an error in the
status byte and asserts ATN, the drive:
• Switches the host to the Message Out Phase and waits
for the host to send 05 (Initiator Detected Error).
• Switches the host to the Status Phase and sends a
Check Condition.
• Target sends restore pointers and resends Status.
Message In Phase
If the host is in the Message In Phase and detects an error
on a message bytes an asserts ATN, the drive:
• Switches the host to the Message Out Phase.
• Waits for the host to send 09 (Parity Error Message).
• Switches the host to the Message In Phase and resends
the message.