LLExec Watchdog
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LLExec have two optional watchdog systems which can be used to protect a target PLC from the process abnormal termination, or locks and starvation.
The two mechanism are the Hardware Watchdog and the Software Watchdog.
Hardware Watchdog
The hardware Watchdog depends on having a controller with a watchdog hardware cicrcuit on the board, and it is realized by a software component - LLExecSupportDaemon which is extern to the LLExec process which perform some diagnostic tasks and collaborate with the LLExec process to handle the hardware circuit.
It works on realtime systems, where, on a given processor, an higher priority task could preempt a lower priority task on the system and and cannot be preempted by a lower priority task.
The Watchdog task in the