Differences

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--- getting_started:tutorials:hal0 [2019/08/14 13:49] – graf
+++ getting_started:tutorials:hal0 [2021/03/31 15:46] – [Accessing Output Signals Directly] ursgraf
@@ Line 1: / Line 1: @@
 ====== Using the HAL with the Simulator ======
-In the EEROS library you will find a directory with examples. Open a shell in the build directory of your EEROS library and run ''examples/hal/halTest1''. The system uses inputs and output. For this reason you will need to install a simple simulator, see [[getting_started:install_wrapper#simulator|]]. The following command will run the example
+The [[eeros_architecture:hal:start|]] provides an interface between the robot control system and the hardware of the robot. As we do not have any real output we will use a simulator, see [[getting_started:install_wrapper#simulator|Simulator]]. The system in this example uses inputs and outputs.
+In the EEROS library you will find a directory with examples. For this example see [[https://github.com/eeros-project/eeros-framework/blob/master/examples/hal/HalTest1.cpp|HalTest1.cpp]].
+Open a shell in the build directory of your EEROS library and run
 <code>
 $ ./halTest1 -c HalTest1Config.json
@@ Line 11: / Line 15: @@
   * 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.