ACTION PRIORITIES IN THE SYSTEM
A mechanism of prioritizing actions performed in the system has been used in the VERTEX control
units in order to ensure the correct operation of the lighting system. This allows setting the priority odf
control signals occurring in the system, e.g. what is more important: automatic control from a motion
sensor or from the time schedule.
DESCRIPTION OF OPERATION
In the VERTEX control units, the priorities of triggered actions are directly related to control groups.
Each action triggered on a given group has its priority which before the action is triggered is compared
with the priority of the previous action. If the priority of the current action is greater or equal to the
priority of the previous action, the current action will be performed. Otherwise, the control unit will not
perform the current action, and the priority will remain at the previous level or will be reset according to
the relationships presented below.
The priorities have values from 0 to 255, but the values from 245 to 255 have a special function
– after
performing an action of such priority, the priority for the comparison with the next action is resent to the
value according to the relationship:
𝑃
𝑁
= {
𝑃
𝑃
𝑤ℎ𝑒𝑛 𝑃
𝐴
< 𝑃
𝑃
𝑃
𝐴
𝑤ℎ𝑒𝑛 𝑃
𝑃
≤ 𝑃
𝐴
< 245
255 − 𝑃
𝐴
𝑤ℎ𝑒𝑛 245 ≤ 𝑃
𝐴
≤ 255
where:
•
𝑃
𝑁
– priority saved after he action is performed
•
𝑃
𝑃
– previous priority, to which the current priority is compared
•
𝑃
𝐴
– priority of the current action
The reset of priorities to lower values is necessary so that the lower-priority actions can be
performed in the future. Without the reset, it will not be possible to perform actions of priority
lower than the last priority performed.
The priority behaviour table:
Priority of the action
Priority after
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