5 fc-al timers, Table 82.fcal timer values – Hitachi ULTRASTAR 15K450 HUS154530VLF400 User Manual

Page 116

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Hitachi Ultrastar 15K450 (FC-AL) Hard Disk Drive Specification

100

17.5 FC-AL timers

Table 87: FCAL timer values

The drive uses FCAL timers as specified in PLDA 2.1 as required in the standard.

• AL_TIME

AL_TIME represents two times the worst case round trip latency for a very large loop.

• LIS_HOLD_TIME

LIS_HOLD_TIME is the maximum amount of time between when a node receives a Loop Initialization Sequence
until it forwards it to the next node.

• R_T_TOV

R_T_TOV is used by the receiver logic to detect a Link Failure. A Link Failure is defined as loss of synchronization
for a period greater than R_T_TOV.

• E_D_TOV

E_D_TOV is the minimum time a port shall wait for the next expected frame in a sequence before detecting an error.

• R_A_TOV

R_A_TOV is defined by the PLDA to be two distinct timers.

• R_A_TOV

SEQ_QUAL

defines the minimum time a port shall wait before reuse of the sequence qualifiers SEQ_CNT

and SEQ_ID. The PLDA defines the value of R_A_TOV

SEQ_QUAL

to be zero seconds.

Twice the value of R_A_TOV

ELS

defines the minimum time a port shall wait for the response to an Extended Link

Service Request. The PLDA defines this value to be two seconds. Therefore a port must wait twice this value (four
seconds) before timing out an ELS.

Note:

In the FLA, there is no split definition of the R_A_TOV value. One timer value is used for both

R_A_TOV

SEQ_QUAL

and R_A_TOV

ELS

.

• RR_TOV

RR_TOV is the minimum time a target shall wait for an Initiator to perform exchange authentication following LIP. If
this timer expires, the Target will implicitly log out the Initiator and free up the resources associated with that timer.
An RR_TOV timer is maintained for each Initiator that has logged in.

Timer Description

Value

(PLDA/FLA)*

AL_TIME

Arbitrated Loop Timeout Value

15 ms

LIS_HOLD_TIME

Loop Initialization Sequence Hold Time

1 ms

R_T_TOV

Receiver Transmitter Timeout Value

100 ms

E_D_TOV

Error Detect Timeout Value

2 sec./2 sec.*

R_A_TOV

Resource Allocation Timeout Value

2 sec./10 sec.*

RR_TOV

Resource Recovery Timeout Value

2 sec.

LP_TOV

Loop Timeout Value

2 sec.

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