|
| Chapter 6 Target Mode |
Page 6 - 18 |
| Target Mode Response Command |
Note
As an example of how to use the bits of the Response Control Flags field, suppose you wish to check the data that the RF3880 receives from an initiator before determining what action to take. You could do the following:
1.On the first Target Mode Response command, set bits 1 to 7 to
2.After determining an action, set bits 1 to 7 as desired (to continue the data transfer or terminate the command) set the CSC bit (bit 0), and issue another Target Mode Response command.
DSC Disconnect SCSI command termination - Use this bit when the SCSI command is not yet complete and you wish to send another Target Mode Response command. Use of this bit will cause the adapter to send the First Message Byte (usually a Save Data Pointer message) followed by the Message Byte, (usually a Disconnect message) and then go to Bus Free phase.
0 ⇒ This option will not be used.
1 ⇒ The adapter will go to Bus Free after sending the First Message Byte followed by the Message Byte.
LSC Linked SCSI command termination - This bit is used to terminate a linked SCSI command and begin receiving the next command. In this case, the adapter will send the Status Byte followed by the Message Byte and then go to Command Phase.
0 ⇒ This option will not be used.
1 ⇒ The adapter will go to Command phase after sending the Status Byte followed by the Message Byte.
SMB Send Message Byte only - Use this bit to cause the adapter to send the First Message Byte (often a Save Data Pointer message) to the initiator after any data transfer is complete, and not go to Bus Free phase.
0 ⇒ This option will not be used.
1 ⇒ The adapter will send the First Message Byte and will not go to Bus Free phase afterward.
Message Byte
Depending on the setting of the NSC or DSC bits of the Response Control Flags field, this field will contain either a Message byte to send after the Status byte (NSC is one), or the second Message byte to send (DSC is one).
Status or 1st Message Byte
Depending on the setting of the NSC and DSC bits of the Response Control Flags field, this field will contain either a status byte (NSC is one), or the first message byte to send (DSC is one).
Queue Tag Identifier
This byte contains the queue tag identifier assigned to this SCSI command by the initiator.
Queue Tag Message
This byte contains a Simple Queue Tag message (20H) if any queue tag message was received from the initiator.
21020285 D | User’s Guide |
