Differences

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--- eeros_architecture:safety_system:usage [2016/11/04 09:49] – [Setup a Safety System] graf
+++ eeros_architecture:safety_system:usage [2017/01/28 17:33] (current) – external edit 127.0.0.1
@@ Line 2: / Line 2: @@
 Every EEROS system can have exactly one safety system. As a first step you have to define your safety properties as described in [[eeros_architecture:safety_system:properties|]]. After this you create an instance of these properties and assign it to your safety system as follows
 <code cpp>
-  MySafetyProperties safetyProperties;
+MySafetyProperties safetyProperties;
-  SafetySystem safetySys(safetyProperties, period);
+SafetySystem safetySys(safetyProperties, period);
 </code>
@@ Line 9: / Line 9: @@
 <code cpp>
-  // Create and run executor
+// Create and run executor
-  auto executor = eeros::Executor::instance();
+auto& executor = eeros::Executor::instance();
-  executor.setPeriod(period);
+executor.setMainTask(safetySys);
-  executor.setMainTask(safetySys);
 </code>
 ===== Changing the Safety Level =====
-The only possibility to change the safety level is through the method //triggerEvent//.
+The central attribute of the safety system is its //currentLevel//. Of course, this level can be queried by everyone but only set by the safety system itself.
+The only possibility to change the safety level is through the method //triggerEvent//. \\
+Triggering an event can be done by
+  * the safety system itself (as a level action or by checking an critical input)
+  * the control system through a special ''SignalChecker'' block
+  * the sequencer
-====== Safety System Usage ======
+An event can be triggered by the control system or the sequencer by calling:
-Since the safety system and the HAL (hardware abstraction layer or hardware access layer) are strongly coupled it makes sense to show the usage of both systems on this page.
+<code cpp>
+safetySys.triggerEvent(safetyProperties.seStartRunning);
+</code>
+Please make sure to declare a safety event public if triggered by the control system or the sequencer. Private event can be triggered solely by the safety system itself.
-Sometimes you need to fire an event e.g. swInitDone:
-<code c>
-safetySys.triggerEvent(swInitDone, privateContext);
-</code>
-The C-style definition in class //SafetySystem//:
-<code c>
-void triggerEvent(uint32_t event);
-</code>
-===== Watchdog Output ====
-The last thing to do, is to set an watchdog output, which will be toggled on every execution of //run()//. This can easily be done with:
-<code c>
-SystemOutput<bool>* watchdog = hal.getLogicSystemOutput("watchdog");
-safetySys.setWatchdogOutput(watchdog);
-</code>
-===== Setting Up The System =====
-Before the safety system can be started, you have to define the entry level:
-<code c>
-safetySys.setEntryLevel(off);
-</code>
-Finally assign the safety system as the main task of the executor, so that the //run()// method will be called periodically (every millisecond, for example).
-<code c>
-executor.setMainTask(safetySys);
-</code>