semaphore TBOX LT2-530 Series, Руководство пользователя, Страница: 140 / 197

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16. Periodic Events
When tasks have to be executed periodically, periodical events
constitute an easy way of creating events to launch the tasks, like
ModBus Transactions, sending of test alarm, datalogging, a piece of Ladder/BASIC logic, etc...,
and this, independently from any other condition.
A periodic event could be compared to an automatic timer.
A digital Tag is Triggered periodically: it is automatically SET when the period has elapsed. All tasks
associated to a positive edge on this Tag will be launched, then the Tag will be automatically RESET, ready
for the next period.
Several tasks can be associated to the Tag triggered. This implies for the OS to RESET the Tag when all tasks
have been launched.
In the project workspace of TWinSoft, a folder is available to declare the Periodic Events: