Hitachi ULTRASTAR 15K450 HUS154530VLF400 - Manual (Page 326)

Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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Table 253: LIxx Frame Payloads
The Loop Initialization Procedure is as follows...
1. Select Initial AL_PA
The initial AL_PA is EFh.
2. Select a Loop Master
LISM frames are continuously transmitted. The D_ID and S_ID fields are set to 0000EFh.
If a LISM frame is received which is the same as the one transmitted, the Port becomes the Loop Master and continues the
procedure at step 3.
For all other received LISM frames...
- If the D_ID is 000000h, the frame is retransmitted.
- If the Port_Name in the payload is greater than the Port_Name, the frame is discarded.
- If the Port_Name in the payload is less than the Port_Name, the frame is retransmitted.
If an ARB(F0) is received, the Port continues the procedure at step 4.
3. Loop Master
a. ARB(F0) is continuously transmitted until ARB(F0) is received.
b. The Port prepares an LIFA frame with an initial AL_PA bit map of all zeros. After transmitting the LIFA frame, the
Port waits to receive a LIPA frame.
c. The AL_PA bit map from the LIFA frame is used in a LIPA frame. If the bit corresponding to the Port’s previously
assigned AL_PA is not set it is set now. If it is already set, the Port attempts to obtain its Hard AL_PA in step d. The
Port transmits the LIPA and waits to receive it back.
d. The AL_PA bit map from the LIPA frame is used in a LIHA frame. If the bit corresponding to the Port’s hard
assigned AL_PA is not set it is set now (unless a bit was set for LIPA). If it is already set, the Port attempts to obtain a
Soft AL_PA in step e. The Port transmits the LIHA and waits to receive it back.
e. The AL_PA bit map from the LIHA frame is used in a LISA frame. If a bit was not set for LIHA, the bit associated
with the lowest priority AL_PA still available is set. This is the Port’s “soft assigned” AL_PA. If no bits are available,
the Port shall stay in non-participating mode. The Port transmits the LISA and waits to receive it back. If byte 3 of the
payload in the received LISA frame is still 01h (indicating that all nodes on the loop support positional mapping) the
drive continues with the next two steps. Otherwise, the next two steps are skipped.
f. The Port creates a LIRP frame with an AL_PA position map of all FFh, except for the first two bytes which are
01xxh (xx is the Port’s AL_PA). The Port transmits the LIRP frame and waits to receive it back.
g. The AL_PA position map from the received LIRP is used to create a LILP frame. The Port transmits the LILP frame
and waits to receive it back.
h. CLS is transmitted to put all other Ports into MONITORING state. When received back, the Loop Master itself goes
to MONITORING state.
4. Non Loop Master
LIxx Frame Payload
LISM 1101 0000h 8 - byte Port_Name
LIFA 1102 0000h 16 - byte AL_PA bit map
LIPA 1103 0000h 16 - byte AL_PA bit map
LIHA 1104 0000h 16 - byte AL_PA bit map
LISA 1105 0000h 16 - byte AL_PA bit map
LIRP 1106 0000h 128 - byte AL_PA position map
LILP 1107 0000h 128 - byte AL_PA position map