IO: Unify ADC examples

gohai · gohai · commit b07707e262a1 · 2018-07-26T00:25:12.000-07:00
diff --git a/java/libraries/io/examples/AnalogDigital_SPI_MCP3001/AnalogDigital_SPI_MCP3001.pde b/java/libraries/io/examples/AnalogDigital_SPI_MCP3001/AnalogDigital_SPI_MCP3001.pde
@@ -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);
 }
diff --git a/java/libraries/io/examples/AnalogDigital_SPI_MCP3001/MCP3001.pde b/java/libraries/io/examples/AnalogDigital_SPI_MCP3001/MCP3001.pde
@@ -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);
diff --git a/java/libraries/io/examples/AnalogDigital_SPI_MCP3008/AnalogDigital_SPI_MCP3008.pde b/java/libraries/io/examples/AnalogDigital_SPI_MCP3008/AnalogDigital_SPI_MCP3008.pde
@@ -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);
 }
diff --git a/java/libraries/io/examples/AnalogDigital_SPI_MCP3008/MCP3008.pde b/java/libraries/io/examples/AnalogDigital_SPI_MCP3008/MCP3008.pde
@@ -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");`