User's Guide

8 SCSI Command Support
EXTENDED MESSAGE 01h Out This message is sent from an initiator to the target
to attempt to negotiate synchronous or wide data
transfers. The library supports both.
SAVE DATA POINTERS 02h In This message is issued before every disconnect
message following a Data In or Data Out phase.
The message is not sent when disconnecting after
a Command Descriptor Block (CDB) that did not
transfer data.
RESTORE POINTERS 03h In This message is sent from the target to direct the
initiator to continue sending data.
DISCONNECT 04h In This message is sent by the target to inform an
initiator that the present data transfer will be
suspended. The target will reselect the initiator at a
later time to continue the current operation.
INITIATOR DETECTED
ERROR
05h Out This message is sent from an initiator to inform the
target that an error occurred. This allows the target
to retry the operation.
ABORT 06h Out This message is sent from the initiator to the target
to clear the current or pending operation. The
target goes directly to the BUS FREE phase after
successful receipt of this message.
MESSAGE REJECT 07h Both This message is sent from the initiator or target to
indicate that the last message received was
inappropriate or not implemented.
NO-OP 08h Out This message is sent from the initiator to inform the
target that no message is valid in response to the
target request for a message.
MESSAGE PARITY
ERROR
09h Out This message is sent from the initiator to the target
to indicate that one or more bytes in the last
message received contained a parity error.
BUS DEVICE RESET 0Ch Out This message is sent from an initiator to clear all
commands, data, and status at the target. When
the target recognizes this message, it aborts the
command currently being executed and proceeds
to the BUS FREE state.
IDENTIFY 80h-
FFh
Both These messages are sent either by the initiator or
by the target to establish (or re-establish) the
logical connection path (nexus) between an initiator
and target for a particular logical unit.
Table 6 Supported SCSI Messages (Continued)
Message Code Direction Description