Smartline discrete alarm does not support bool, which may be because discrete alarm is usually used to monitor and notify discrete events in the system, such as state changes and trigger conditions. A discrete event refers to an event with a definite state, usually "on" or "off", "yes" or "no", rather than a continuously changing value. Therefore, discrete alarms are more suitable for handling discrete events than continuous Boolean values.

In intelligent system, discrete alarm can be used to monitor the change of equipment state, such as the trigger of sensor and the change of switch state. The triggering of these events usually requires issuing an alarm or triggering a specific response action in order to take appropriate measures in time.

On the other hand, continuous Boolean values are usually used to represent logical conditions rather than discrete events. When dealing with continuous data, different technologies and methods are usually used, such as threshold detection and data analysis. Applying continuous Boolean values to discrete alarms may lead to inaccurate results, because discrete alarms are more suitable for dealing with discrete state changes.