comparison examples/03-Analog/scope-analog/render.cpp @ 542:3016638b4da2 prerelease

Analog examples updated

 {
 
     // setup the scope with 3 channels at the audio sample rate
 	scope.setup(3, context->audioSampleRate);
 	
+	// Check if analog channels are enabled
+	if(context->analogFrames == 0 || context->analogFrames > context->audioFrames) {
+		rt_printf("Error: this example needs analog enabled, with 4 or 8 channels\n");
+		return false;
+	}
+
+	// Check that we have the same number of inputs and outputs.
+	if(context->audioInChannels != context->audioOutChannels ||
+			context->analogInChannels != context-> analogOutChannels){
+		printf("Error: for this project, you need the same number of input and output channels.\n");
+		return false;
+	}
+	
 	gInverseSampleRate = 1.0 / context->audioSampleRate;
 	gPhase = 0.0;
 
 	return true;
 }

 	    
 	    // 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;
+	    for(unsigned int channel = 0; channel < context->audioOutChannels; channel++) {
+	        audioWrite(context, n, channel, out);
+	    }
+			
 
 	}
 }
 
 void cleanup(BelaContext *context, void *userData)

 
 
 /**
 \example scope-analog/render.cpp
 
-Connecting potentiometers
+Scoping sensor input
 -------------------------
 
-This example reads from analogue inputs 0 and 1 via `analogReadFrame()` and 
+This example reads from analogue inputs 0 and 1 via `analogRead()` and 
 generates a sine wave with amplitude and frequency determined by their values. 
 It's best to connect a 10K potentiometer to each of these analog inputs. Far 
 left and far right pins of the pot go to 3.3V and GND, the middle should be 
 connected to the analog in pins.
 
 The sine wave is then plotted on the oscilloscope. Click the Open Scope button to 
 view the results. As you turn the potentiometers you will see the amplitude and 
-frequency of the sine wave change.
+frequency of the sine wave change. You can also see the two sensor readings plotted
+on the oscilloscope.
+
+The scope is initialised in `setup()` where the number of channels and sampling rate
+are set.
+
+`````
+scope.setup(3, context->audioSampleRate);
+`````
+
+We can then pass signals to the scope in `render()` using:
+
+``````
+scope.log(out, in1, in2);
+``````
 
 This project also shows as example of `map()` which allows you to re-scale a number 
 from one range to another. Note that `map()` does not constrain your variable 
 within the upper and lower limits. If you want to do this use the `constrain()`
 function.