SAS Interface

If the phy supports the physical link rate, it shall attempt to synchronize on an incoming series of dwords at that rate for the SNLT. The received dwords may be ALIGN (0) or ALIGN (1) primitives. If the phy achieves dword synchronization within the SNLT, it shall change from transmitting ALIGN (0) primitives to transmitting ALIGN (1) primitives for the remainder of the SNTT (i.e., the remainder of the speed negotiation window). If the phy does not achieve dword synchronization within the SNLT, it shall continue transmitting ALIGN (0)s for the remainder of the SNTT (i.e., the remainder of the speed negotiation window).

At the end of the SNTT, if a phy is both transmitting and receiving ALIGN (1) primitives, it shall consider that physical link rate valid. The phy shall then proceed to the next speed negotiation window. A phy shall participate in all speed negotiation windows:

a)up to its highest supported physical link rate plus one; or

b)until it runs a speed negotiation window that does not detect a valid physical link rate after having detected a valid physical link rate in a previous speed negotiation window.

If the phy has detected a valid physical link rate in the previous speed negotiation window, it shall enter the final speed negotiation window using the highest previously successful link rate.

Figure 1.12 shows speed negotiation between a phy A that supports G1 through

G3 link rates and a phy B that only supports the G2 link rate. Both phys run:

1)the G1 speed negotiation window, supported by phy A but not by phy B;

2)the G2 speed negotiation window, supported by both phys; and

3)the G3 speed negotiation window, supported by phy A but not by phy B.

Both phys then select G2 for the final speed negotiation window to establish the negotiated physical link rate.

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Fujitsu MBA3073RC, MBC2036RC, MBC2073RC, MBA3300RC, MBA3147RC specifications SAS Interface