Fujitsu MBC2073RC Manual Do Utilizador

38 

C141-C013 

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When the COMINIT signal cannot be detected 

When a drive sends the COMINIT signal but the COMINIT signal from the 
other side cannot be detected, the drive waits for the reception of the 
COMINIT signal from the INIT or expander until the hot-plug timeout time 
(500 ms) elapses.  If the hot-plug timeout time elapses before the COMINIT 
signal from the other side has been received, the drive sends the COMINIT 
signal again to start a new link reset sequence.  If the drive receives the 
COMSAS signal while waiting for the COMINIT signal, it sends the 
COMSAS signal and takes the OOB sequence as having been performed 
successfully in spite of the fact that it has not received the COMINIT signal. 

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When the COMSAS signal cannot be detected 

When a drive sends the COMSAS signal but the COMSAS signal from the 
other side cannot be detected, the drive waits for the reception of the 
COMSAS signal from the INIT or expander until the hot-plug timeout time 
(500 ms) elapses.  If the hot-plug timeout time elapses before the COMSAS 
signal from the other side has been received, the drive sends the COMSAS 
signal again to start a new link reset sequence. 

The SAS speed negotiation sequence is a peer-to-peer negotiation technique that 
does not assume initiator and target (i.e., host and device) roles. The sequence 
consists of a set of speed negotiation windows for each physical link rate, starting 
with 1,5 Gbps, then 3,0 Gbps, then the next rate. The length of the speed 
negotiation sequence is determined by the number of physical link rates supported 
by the phys. 

Figure 1.11 defines the speed negotiation window, including: 

a)  speed negotiation window time; 

b)  rate change delay time (RCDT); 

c)  speed negotiation transmit time (SNTT); and 

d)  speed negotiation lock time (SNLT).