Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification
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not one, the drive will respond with an LS_RJT containing a reason code of 03h “Logical error”, and a reason code
explanation of 0Fh “Invalid Common Service Parameters”. The drive returns a 1b in this field.
• RRO - Random Relative Offset
When set to one, this flag indicates that the Port supports Random Relative Offset within a Sequence. The Relative
Offset is only present if bit 3 of the F_CTL field in the frame header is set to 1b. The drive returns a 0b in this field.
• VV - Vali d Vend o r Vers ion L evel
When set to one, this flag indicates that the Vendor Version Level field in the frame payload contains valid informa-
tion. The drive returns a 0b in this field.
• N/F Port - N_Port/F_Port
When set to one, this flag indicates that the Port is an F_Port. When set to zero, it is an N_Port. The drive returns a 0b
in this field.
• ABCM - Alternate BB-Credit Model
When set to one, this flag indicates that the Port supports the Alternate BB-Credit model. The drive returns a 1b in
this field.
• E_D_TOV - E_D_TOV Resolution
When set to one, this flag indicates that the resolution of the E_D_TOV timer shall be 1 ns. When set to zero, the res-
olution shall be 1 ms. The flag is only applicable in a point to point topology. The drive returns a 0b in this field.
• DS - Dedicated Simplex
Only applies to class 1 service. The drive sets this field to 0b.
• DHD - Dynamic Half Duplex
When set to one, this flag indicates that the Port supports Dynamic Half Duplex. The drive returns a 0b in this field.
•SEQ_CNT - SEQ_CNT
When set to one, this flag indicates that the Port is guaranteeing that it will transmit all frames within an Exchange
using a continuously increasing SEQ_CNT. If set to zero, normal FC_PH rules regarding SEQ_CNT usage apply. The
drive returns a 0b in this field.
• PL - Payload Length
When set to one, this flag indicates that PLOGI Payload Length shall be 256 bytes. If set to zero, the flag specifies
that the normal 116 byte PLOGI Payload specified in FC-PH-2 is used. The drive returns a 0b in this field.
The Buffer-to-Buffer Receive Data_Field Size field (word 2, bits 11-0) specifies the largest FT_1 frame Data_Field Size that
may be received by the Nx_Port supplying the Service Parameters as a Sequence Recipient for:
a) a connect-request (SOFc1),
b) a Class 2 Data frame, or
c) a Class 3 Data frame
Values less than 256 or greater than 2 112 are invalid and shall be a multiple of four bytes. An Fx_Port shall support a Data
Field size of at least 256 bytes.
The Total Concurrent Sequences field indicates the number of concurrent sequences that the Port can support for all 3
classes. The value sent must be > 0, or the drive will respond with an LS_RJT with a reason code of 03h “Logical error” and a
reason code explanation of 09h “Service Parm error - Concurrent Seq”. The drive returns a value of FFh in this field.
The Relative Offset by Information Category field is all flags. The bit position of each set (1) bit determines the Information
Category; e.g., if Relative Offset is supported for category 0001b (Solicited Data), bit 1 is set. The drive returns a value of
0002h in this field (Relative Offset supported for Solicited Data only).