comparison examples/scope_analogue/render.cpp @ 300:dbeed520b014 prerelease

Renamed projects to examples

+// this example reads the analogue inputs 0 and 1
+// and generates a sine wave with an amplitude and
+// frequency determined by their values
+// it then plots these on the oscilloscope
+
+#include <BeagleRT.h>
+#include <cmath>
+#include <Scope.h>
+
+Scope scope;
+
+float gInverseSampleRate;
+float gPhase;
+
+bool setup(BeagleRTContext *context, void *userData)
+{
+
+    // setup the scope with 3 channels at the audio sample rate
+	scope.setup(3, context->audioSampleRate);
+	
+	gInverseSampleRate = 1.0 / context->audioSampleRate;
+	gPhase = 0.0;
+
+	return true;
+}
+
+void render(BeagleRTContext *context, void *userData)
+{
+
+	for(unsigned int n = 0; n < context->audioFrames; n++) {
+	    
+	    // read analogIn channels 0 and 1
+	    float in1 = analogReadFrame(context, n, 0);
+	    float in2 = analogReadFrame(context, n, 1);
+	    
+	    // map in1 to amplitude and in2 to frequency
+	    float amplitude = in1 * 0.8f;
+	    float frequency = map(in2, 0, 1, 100, 1000);
+	    
+	    // generate a sine wave with the amplitude and frequency 
+	    float out = amplitude * sinf(gPhase);
+	    gPhase += 2.0 * M_PI * frequency * gInverseSampleRate;
+		if(gPhase > 2.0 * M_PI)
+			gPhase -= 2.0 * M_PI;
+	    
+	    // log the sine wave and sensor values on the scope
+	    scope.log(out, in1, in2);
+	    
+	    // pass the sine wave to the audio outputs
+	    for(unsigned int channel = 0; channel < context->audioChannels; channel++)
+			context->audioOut[n * context->audioChannels + channel] = out;
+
+	}
+}
+
+void cleanup(BeagleRTContext *context, void *userData)
+{
+
+}