Teledyne LeCroy SAS Suite User Manual - Manual (Page 69)

SASSuite User Manual Version 6.25
LeCroy Corporation
59
Multiple Parallel Events
When multiple events are defined in Global Rules, the events are operating in parallel
and will continue to remain active (even if they have occurred one or more times) until
recording is stopped. In the example below, three different events have been defined
which will all cause an action on the " EXT OUT" SMA output at the rear of the unit. In
addition, one event (a SCSI HARD_RESET primitive) will alert the user with a beep. As
long as recording continues, these events will continue to cause their defined outputs on
the "EXT OUT" SMA output and/or beeper.
Building
Sequences
Sequences differ from Global Rules in that sequences may have multiple states defined,
although only one state within a sequence is active at any given time. However, all events
within that state are active and operating in parallel. This allows for branching and looping
between states, where State 0 (which is always the starting state) can call another state
depending on a specified sequence of events, and that state can in turn call a different
state, or can call the original state.
Note: There is an upper limit of 256 states that can be defined within any
one sequence.
Note: Sequences allow a state to contain multiple conditions that result in
branches to different other states. For example, if event A results in
a branch to State 2, and event B results in a branch to State 3, then
the sequence will branch to either State 2 or State 3, depending on
which event occurs first.
As another simple example to explain how this works, suppose we want to create some
type of handshake between an Avalanche unit and an external device. We want the
Avalanche unit to look for a SCSI Check Condition, inform the external device when one
is detected, and then allow the external device to complete some task before starting to
watch for the next Check Condition.