B.3. R2TSN/DataSN Use Examples
B.3. R2TSN/DataSN 사용 예제
Output (write) data DataSN/R2TSN Example
데이터 출력 (쓰기) DataSN/R2TSN 예제
+------------------+-----------------------+----------------------+
|Initiator Function| PDU Type & Content | Target Function |
+------------------+-----------------------+----------------------+
| Command request |SCSI Command (WRITE)>>>| Receive command |
| (write) | | and queue it |
+------------------+-----------------------+----------------------+
| | | Process old commands |
+------------------+-----------------------+----------------------+
| | <<< R2T | Ready for data |
| | R2TSN = 0 | |
+------------------+-----------------------+----------------------+
| | <<< R2T | Ready for more data |
| | R2TSN = 1 | |
+------------------+-----------------------+----------------------+
| Send Data | SCSI Data-Out >>> | Receive Data |
| for R2TSN 0 | DataSN = 0, F=0 | |
+------------------+-----------------------+----------------------+
| Send Data | SCSI Data-Out >>> | Receive Data |
| for R2TSN 0 | DataSN = 1, F=1 | |
+------------------+-----------------------+----------------------+
| Send Data | SCSI Data >>> | Receive Data |
| for R2TSN 1 | DataSN = 0, F=1 | |
+------------------+-----------------------+----------------------+
| | <<< SCSI Response |Send Status and Sense |
| | ExpDataSN = 0 | |
+------------------+-----------------------+----------------------+
| Command Complete | | |
+------------------+-----------------------+----------------------+Input (read) data DataSN Example
입력 (읽기) 데이터 DataSN 예제
+------------------+-----------------------+----------------------+
|Initiator Function| PDU Type | Target Function |
+------------------+-----------------------+----------------------+
| Command request |SCSI Command (READ)>>> | |
| (read) | | |
+------------------+-----------------------+----------------------+
| | | Prepare Data Transfer|
+------------------+-----------------------+----------------------+
| Receive Data | <<< SCSI Data-In | Send Data |
| | DataSN = 0, F=0 | |
+------------------+-----------------------+----------------------+
| Receive Data | <<< SCSI Data-In | Send Data |
| | DataSN = 1, F=0 | |
+------------------+-----------------------+----------------------+
| Receive Data | <<< SCSI Data-In | Send Data |
| | DataSN = 2, F=1 | |
+------------------+-----------------------+----------------------+
| | <<< SCSI Response |Send Status and Sense |
| | ExpDataSN = 3 | |
+------------------+-----------------------+----------------------+
| Command Complete | | |
+------------------+-----------------------+----------------------+Bidirectional DataSN Example
양방향 DataSN 예제
+------------------+-----------------------+----------------------+
|Initiator Function| PDU Type | Target Function |
+------------------+-----------------------+----------------------+
| Command request |SCSI Command >>> | |
| (Read-Write) | Read-Write | |
+------------------+-----------------------+----------------------+
| | | Process old commands |
+------------------+-----------------------+----------------------+
| | <<< R2T | Ready to process |
| | R2TSN = 0 | WRITE command |
+------------------+-----------------------+----------------------+
| * Receive Data | <<< SCSI Data-In | Send Data |
| | DataSN = 1, F=0 | |
+------------------+-----------------------+----------------------+
| * Receive Data | <<< SCSI Data-In | Send Data |
| | DataSN = 2, F=1 | |
+------------------+-----------------------+----------------------+
| * Send Data | SCSI Data-Out >>> | Receive Data |
| for R2TSN 0 | DataSN = 0, F=1 | |
+------------------+-----------------------+----------------------+
| | <<< SCSI Response |Send Status and Sense |
| | ExpDataSN = 3 | |
+------------------+-----------------------+----------------------+
| Command Complete | | |
+------------------+-----------------------+----------------------+*) Send data and Receive Data may be transferred simultaneously as in an atomic Read-Old-Write-New or sequentially as in an atomic Read-Update-Write (in the latter case the R2T may follow the received data).
*) 전송 데이터와 수신 데이터는 원자적 읽기-이전-쓰기-새로 전송되는 것과 같이 동시에 전송될 수도 있고, 원자적 읽기-업데이트-쓰기와 같이 순차적으로 전송될 수도 있습니다 (후자의 경우 R2T는 수신된 데이터 뒤에 올 수 있음).
Unsolicited and immediate output (write) data with DataSN Example
DataSN 예제를 사용한 요청되지 않은 데이터 및 즉시 출력 (쓰기) 데이터
+------------------+-----------------------+----------------------+
|Initiator Function| PDU Type & Content | Target Function |
+------------------+-----------------------+----------------------+
| Command request |SCSI Command (WRITE)>>>| Receive command |
| (write) |F=0 | and data |
|+ Immediate data | | and queue it |
+------------------+-----------------------+----------------------+
| Send Unsolicited | SCSI Write Data >>> | Receive more Data |
| Data | DataSN = 0, F=1 | |
+------------------+-----------------------+----------------------+
| | | Process old commands |
+------------------+-----------------------+----------------------+
| | <<< R2T | Ready for more data |
| | R2TSN = 0 | |
+------------------+-----------------------+----------------------+
| Send Data | SCSI Write Data >>> | Receive Data |
| for R2TSN 0 | DataSN = 0, F=1 | |
+------------------+-----------------------+----------------------+
| | <<< SCSI Response |Send Status and Sense |
| | | |
+------------------+-----------------------+----------------------+
| Command Complete | | |
+------------------+-----------------------+----------------------+