@@ -9,5 +9,12 @@ void setup() {
 }
 
 void draw() {
-  background(adc.getAnalog() * 255);
+  // this will return a number between 0 and 1
+  float measured = adc.analogRead();
+
+  // multiply with the supply voltage to get an absolute value
+  float volts = 3.3 * measured;
+  println("Analog Input is " + volts + "V");
+
+  background(measured * 255);
 }
@@ -10,7 +10,8 @@ class MCP3001 extends SPI {
     settings(500000, SPI.MSBFIRST, SPI.MODE0);
   }
 
-  float getAnalog() {
+  // returns a number between 0.0 and 1.0
+  float analogRead() {
     // dummy write, actual values don't matter
     byte[] out = { 0, 0 };
     byte[] in = transfer(out);
 
@@ -9,7 +9,14 @@ void setup() {
 }
 
 void draw() {
-  background(adc.getAnalog(0) * 255);
-  fill(adc.getAnalog(1) * 255);
+  // this will return a number between 0 and 1
+  float measured = adc.analogRead(0);
+
+  // multiply with the supply voltage to get an absolute value
+  float volts = 3.3 * measured;
+  println("Analog Input 0 is " + volts + "V");
+
+  background(255);
+  fill(measured * 255);
   ellipse(width/2, height/2, width * 0.75, width * 0.75);
 }
@@ -11,7 +11,8 @@ class MCP3008 extends SPI {
     settings(500000, SPI.MSBFIRST, SPI.MODE0);
   }
 
-  float getAnalog(int channel) {
+  // returns a number between 0.0 and 1.0
+  float analogRead(int channel) {
     if (channel < 0 ||  7 < channel) {
       System.err.println("The channel needs to be from 0 to 7");
       throw new IllegalArgumentException("Unexpected channel");
Original file line number	Diff line number	Diff line change
@@ -9,5 +9,12 @@ void setup() {
9	9	}
10	10
11	11	void draw() {
12		- background(adc.getAnalog() * 255);
	12	+ // this will return a number between 0 and 1
	13	+ float measured = adc.analogRead();
	14	+
	15	+ // multiply with the supply voltage to get an absolute value
	16	+ float volts = 3.3 * measured;
	17	+ println("Analog Input is " + volts + "V");
	18	+
	19	+ background(measured * 255);
13	20	}
Original file line number	Diff line number	Diff line change
@@ -10,7 +10,8 @@ class MCP3001 extends SPI {
10	10	settings(500000, SPI.MSBFIRST, SPI.MODE0);
11	11	}
12	12
13		- float getAnalog() {
	13	+ // returns a number between 0.0 and 1.0
	14	+ float analogRead() {
14	15	// dummy write, actual values don't matter
15	16	byte[] out = { 0, 0 };
16	17	byte[] in = transfer(out);
Original file line number	Diff line number	Diff line change
@@ -11,7 +11,8 @@ class MCP3008 extends SPI {
11	11	settings(500000, SPI.MSBFIRST, SPI.MODE0);
12	12	}
13	13
14		- float getAnalog(int channel) {
	14	+ // returns a number between 0.0 and 1.0
	15	+ float analogRead(int channel) {
15	16	if (channel < 0 \|\| 7 < channel) {
16	17	System.err.println("The channel needs to be from 0 to 7");
17	18	throw new IllegalArgumentException("Unexpected channel");