comparison examples/02-Digital/digital-output/render.cpp @ 464:8fcfbfb32aa0 prerelease

Examples reorder with subdirectories. Added header to each project. Moved Doxygen to bottom of render.cpp.

+/*
+ ____  _____ _        _    
+| __ )| ____| |      / \   
+|  _ \|  _| | |     / _ \  
+| |_) | |___| |___ / ___ \ 
+|____/|_____|_____/_/   \_\
+
+The platform for ultra-low latency audio and sensor processing
+
+http://bela.io
+
+A project of the Augmented Instruments Laboratory within the
+Centre for Digital Music at Queen Mary University of London.
+http://www.eecs.qmul.ac.uk/~andrewm
+
+(c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
+  Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
+  Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
+
+The Bela software is distributed under the GNU Lesser General Public License
+(LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
+*/
+
+
+#include <Bela.h>
+#include <cmath>
+#include <rtdk.h>
+
+bool setup(BelaContext *context, void *userData)
+{
+    pinMode(context, 0, P8_07, OUTPUT);
+	return true;
+}
+
+void render(BelaContext *context, void *userData)
+{
+  static int count=0; //counts elapsed samples
+  float interval=0.5; //how often to toggle the LED (in seconds)
+  static int status=GPIO_LOW;
+	for(unsigned int n=0; n<context->digitalFrames; n++){
+    if(count==context->digitalSampleRate*interval){ //if enough samples have elapsed
+      count=0; //reset the counter
+    // status=digitalRead(context, 0, P8_07);
+      if(status==GPIO_LOW) { //toggle the status
+          digitalWrite(context, n, P8_07, status); //write the status to the LED
+          status=GPIO_HIGH;
+      }
+      else {
+          digitalWrite(context, n, P8_07, status); //write the status to the LED
+          status=GPIO_LOW;
+      }
+    }
+    count++;
+  }
+}
+
+void cleanup(BelaContext *context, void *userData)
+{
+	// Nothing to do here
+}
+
+/* ------------ Project Explantation ------------ */
+
+/**
+\example 02-digital-output
+
+Blinking an LED
+---------------
+
+This sketch shows the simplest case of digital out. 
+
+- Connect an LED in series with a 470ohm resistor between P8_07 and ground. 
+
+The led is blinked on and off by setting the digital pin `HIGH` and `LOW` every interval seconds which is set in 
+`render()`.
+
+In `setup()` the pin mode must be set to output mode via `pinMode()`. For example: 
+`pinMode(context, 0, P8_07, OUTPUT)`. 
+In `render()` the output of the digital pins is set by `digitalWrite()`. For example: 
+`digitalWrite(context, n, P8_07, status)` where `status` can be equal to 
+either `HIGH` or `LOW`. When set `HIGH` the pin will give 3.3V, when set to 
+`LOW` 0V.
+
+To keep track of elapsed time we have a sample counter count. When the count reaches 
+a certain limit it switches state to either `HIGH` or `LOW` depending on its current 
+value. In this case the limit is `context->digitalSampleRate*interval` which 
+allows us to write the desired interval in seconds, stored in `interval`.
+*/
+