Ultrastar C10K600 OEM Specification

17.5.4 SAS Speed Negotiation

The Drive supports G1 (1.5 Gbps), G2 (3.0 Gbps), and G3 (6.0 Gbps) negotiation speeds. The default maximum negotiation rate is G3 speed (per byte 32 in the Phy Control and Discover Mode Page 19 subpage 1). Drive is SAS2 device and supports

SNW-1, SNW-2, and SNW-3 speed negotiation with Phy capabilities exchange, and training (Train-SNW). Phy capabilities is defined in table below:

Phy Capabilities:

Byte /Bit

0

1

7 6

Start =1b TX SSC

Type = 0b

G1 Without

SSC=1b

G1 With

SSC=1b

5

Reserved

G2 Without

SSC=1b

4

G2 With

SSC=1b

3 2 1 0

Requested Logical Link Rate = 0h

G3 Without

SSC=1b

G3 With

SSC=1b

Reserved

2

3

Reserved

Reserved

Parity

•

Start bit is 1 to indicate the beginning of the Phy capabilities

• TX SSC Type bit is set to 1 to indicate that Phy’s transmitter uses center-spreading SSC when SSC is enabled.

A TX SSC TYPE bit set to 0 indicates that Phy’s transmitter uses down-spreading SSC when SSC is enabled.

• Request Logical Link Rate field is 0 to indicate that drive does not support multiplexing

• G1 Without SSC bit set to 1 indicates that drive supports G1(1.5 Gbps) without SSC

• G2 Without SSC bit set to 1 indicates that drive supports G2(3.0 Gbps) without SSC

• G3 Without SSC bit set to 1 indicates that drive supports G3(6.0 Gbps) without SSC

• G1 With SSC bit set to 1 indicates that drive supports G1(1.5 Gbps) with SSC

• G2 With SSC bit set to 1 indicates that drive supports G2(3.0 Gbps) with SSC

• G3 With SSC bit set to 1 indicates that drive supports G3(6.0 Gbps) with SSC

•

Parity bit is set to 1 for even parity of the total number of SNW-3 phy capabilities, including Start bit

.

Training is based on the highest untried commonly supported settings on the exchanged SNW-3 supported settings bits. If a

Train-SNW is invalid and there are additional, untried, commonly supported settings exchanged during SNW-3, then a new

Train-SNW will be performed based on the next highest untried, commonly supported settings. Table 23 defines the priority of

the supported settings bits.

Table 23: Supported Settings Bit Priorities

Priority

Highest

...

...

...

...

Lowest

Bit

G3 With SSC bit

G3 Without SSC bit

G2 With SSC bit

G2 Without SSC bit

G1 With SSC bit

G3 Without SSC bit

HGST Ultrastar C10K600 (SAS) Hard Disk Drive Specification

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