Rockwell Automation 57C610 Enhanced Basic Language, AutoMax User Manual
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6Ć19
Note that it is possible to disable the timeout period for a hardware
event. Disable the timeout for I/O modules that, unlike the Resolver
module, do not generate a periodic interrupt. This format of the
event definition should be used carefully since the timeout provides
an extra level of protection in the event of a hardware failure. The
following is the alternate hardware EVENT NAME format:
EVENT NAME=event_name,
&
INTERRUPT_STATUS = I/O_variable_name,
&
TIMEOUT = DISABLED
Example:
10 COMMON IO_INT_REG%
.
.
.
90 EVENT NAME=HW_EV1,
&
INTERRUPT_STATUS=IO_INT_REG%,
&
TIMEOUT=DISABLED
The format is identical to that for a hardware event except that the
word DISABLED" is entered in place of an integer constant for the
timeout period. The timeout field cannot be left off or set to zero (0).
This forces the user to turn off the timeout by entering the word
DISABLED".
Note that the limit on the number of hardware and software events in
all tasks in a rack is 32.
6.6.2
SET and WAIT ON Statements
The SET statement is used to set an event or indicate that it has
occurred. Executing this statement makes any other tasks that were
suspended while waiting for that event to occur (or setting of that
event) eligible to run. WAIT ON causes task execution to stop until
the EVENT NAME is set by the SET statement. The format of the
SET statement is:
SET event_name
where:
event_name =
name of the hardware or software event previously defined by at
least one task
The format of the WAIT ON statement is:
WAIT ON event_name
where:
event_name =
previously defined by at least one task; same as the
corresponding SET statement.
The following is an example of EVENT NAME, SET, and WAIT ON
statements. Task ABC is performing a calculation every 40
milliĆseconds. Task XYZ is suspended waiting for event GAIN_OVER
to occur so that it can perform some calculations of its own. Task
XYZ needs to run only when event GAIN_OVER occurs, which, in
this example, will indicate that the variable GAIN is beyond a certain
maximum.