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--- getting_started:tutorials:hal0 [2019/03/02 16:57] – graf
+++ getting_started:tutorials:hal0 [2019/09/19 12:14] – [Accessing Output Signals Directly] graf
@@ Line 5: / Line 5: @@
 </code>
 This examples creates a small control system with a couple of peripheral input and output blocks as shown below.
-[{{ :getting_started:tutorials:haltest1.png?300 |//Control system of the test program// }}]
+ [{{ :getting_started:tutorials:haltest1.png?300 | //Control system of the test program// }}]
 The dashed lines denote the feedback of the signals by the simulator. \\
 The main sequence alters the values on digital and analog outputs periodically. A separate periodic task logs the digital and analog inputs.
@@ Line 11: / Line 11: @@
   * A constant value is output to analog output 0 and 2. These values change every 10 seconds. Both are reflected onto analog inputs 0 and 2, respectively.
+===== Accessing Output Signals Directly =====
+A peripheral output block delivers a signal to external hardware. Its signal value can be accessed with a get method, see line 46 in the comment in the example code in ''halTest1.cpp''.
+Alternatively the signal in the HAL could be accessed by getting an reference to the corresponding output block with
+<code cpp>
+auto digOut = hal.getLogicOutput("dOut0", false);  //line 42
+</code>
+The signal value can then be logged with
+block with
+<code cpp>
+log.info() << digOut->get(); // line 47
+</code>
+You have to make sure to access the output with non-exclusive rights, because the control system already has a handle to it, see line 28 in ''halTest1.hpp''. Likewise, the control system must access the same output in the same fashion.