## Tutorial.SwitchCase History

June 01, 2010, at 11:08 PM by Equipo Traduccion -
Changed lines 3-5 from:

to:

## Estructura Switch (caso)

June 01, 2010, at 11:02 PM by Equipo Traduccion -
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Changed lines 8-10 from:

el programa primero lee la tensión en la fotoresistencia. después utiliza la función `map()` para asignar de manera proporcional cuatro estados: 0, 1, 2, y 3. Finalmente, se usa la estructura de control switch para enviar al PC un mensaje dependiendo de cual valor de luminosidad se haya leído.

to:

El programa primero lee la tensión en la fotoresistencia. después utiliza la función `map()` para asignar de manera proporcional cuatro estados: 0, 1, 2, y 3. Finalmente, se usa la estructura de control switch para enviar al PC un mensaje dependiendo de cual valor de luminosidad se haya leído.

June 01, 2010, at 11:00 PM by Equipo Traduccion -
Changed lines 1-18 from:

Examples > Control Structures

## Switch (case) Statement

### used with sensor input

An if statement allows you to choose between two discrete options, TRUE or FALSE. When there are more than two options, you can use multiple if statements, or you can use the switch statement. Switch allows you to choose between several discrete options. This tutorial shows you how to use it to switch between four desired states of a photo resistor: really dark, dim, medium, and bright.

The sketch first reads the photoresistor. Then it uses the `map()` function to map its output to one of four values: 0, 1, 2, or 3. Finally, it uses the `switch()` statement to print one of four messages back to the computer depending on which of the four values is returned.

### Circuit

The photoresistor is connected to analog in pin 0 using a voltage divider circuit. A 10Kilohm resistor makes up the other side of the voltage divider, running from analog in 0 to ground. The `analogRead()` function returns a range of about 0 to 600 from this circuit in a reasonably lit indoor space.

click the image to enlarge

to:

Ejempos > Estructuras de Control

## Switch (caso)

Una estructura 'if' te permite decidir entre dos opciones , verdadero o falso. cuando existe más de una opción, puedes usar muchos if o puedes usar la estructura switch. La estructura switch te permite elegir entre muchas opciones discretas. Este tutorial muestra como usar la estructura switch para elegir una opción dependiendo de cuatro estados diferentes en los que puede estar una foto resistencia: oscuro, poca ilumnicación, mediana iluminación y claro.

el programa primero lee la tensión en la fotoresistencia. después utiliza la función `map()` para asignar de manera proporcional cuatro estados: 0, 1, 2, y 3. Finalmente, se usa la estructura de control switch para enviar al PC un mensaje dependiendo de cual valor de luminosidad se haya leído.

### Circuito

La fotoresistencia se conecta a el pin 0 de entrada analógica usando un divisor de tensión. Una resistencia de 10K es la que se colocará en la otra resistencia del divisor de tensión, conectada entre la entrada analógica 0 y masa. La función `analogRead()` devuelve un valor en un rango de entre 0 y 600 aproximadamente si nos encontramos en una habitación razonablemente iluminada.

haz click en la imagen para aumentar

Changed lines 20-26 from:

image developed using Fritzing. For more circuit examples, see the Fritzing project page

Schematic:

click the image to enlarge

to:

imagen hecha usando Fritzing. Para más circuitos de ejemplo vista Fritzing project page

Esquemático:

haz click en la imagen para aumentar

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### Código

February 23, 2010, at 11:27 PM by Tom Igoe -
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February 23, 2010, at 11:27 PM by Tom Igoe -
Changed lines 33-52 from:
``` /*
Switch statement

Demonstrates the use of a switch statement.  The switch
statement allows you to choose from among a set of discrete values
of a variable.  It's like a series of if statements.

To see this sketch in action, but the board and sensor in a well-lit
down over the sensor.

The circuit:

created 1 Jul 2009
by Tom Igoe

http://www.arduino.cc/en/Tutorial/SwitchCase
*/
```
to:
Changed lines 35-68 from:
to:
August 27, 2009, at 08:48 PM by Tom Igoe -

image developed using Fritzing. For more circuit examples, see the Fritzing project page

July 05, 2009, at 07:27 PM by Tom Igoe -
Changed lines 28-31 from:

[@ /*

```  Switch statement
```
to:
Changed lines 51-53 from:
``` Demonstrates the use of a switch statement.  The switch
statement allows you to choose from among a set of discrete values
of a variable.  It's like a series of if statements.
```
to:
``` // these constants won't change:
const int sensorMin = 0;      // sensor minimum, discovered through experiment
const int sensorMax = 600;    // sensor maximum, discovered through experiment
```
Changed lines 55-57 from:
``` To see this sketch in action, but the board and sensor in a well-lit
down over the sensor.
```
to:
``` void setup() {
// initialize serial communication:
Serial.begin(9600);
}
```
Changed lines 60-62 from:
``` The circuit:
```
to:
``` void loop() {
// map the sensor range to a range of four options:
int range = map(sensorReading, sensorMin, sensorMax, 0, 3);
```
Changed lines 66-67 from:
``` created 1 Jul 2009
by Tom Igoe
```
to:
```   // do something different depending on the
// range value:
switch (range) {
case 0:    // your hand is on the sensor
Serial.println("dark");
break;
case 1:    // your hand is close to the sensor
Serial.println("dim");
break;
case 2:    // your hand is a few inches from the sensor
Serial.println("medium");
break;
case 3:    // your hand is nowhere near the sensor
Serial.println("bright");
break;
}
```
Changed lines 83-119 from:
``` http://www.arduino.cc/en/Tutorial/SwitchCase
*/
```

// these constants won't change: const int sensorMin = 0; // sensor minimum, discovered through experiment const int sensorMax = 600; // sensor maximum, discovered through experiment

void setup() {

```  // initialize serial communication:
Serial.begin(9600);
```

}

void loop() {

```  // read the sensor:
// map the sensor range to a range of four options:
int range = map(sensorReading, sensorMin, sensorMax, 0, 3);
```

```  // do something different depending on the
// range value:
switch (range) {
case 0:    // your hand is on the sensor
Serial.println("dark");
break;
case 1:    // your hand is close to the sensor
Serial.println("dim");
break;
case 2:    // your hand is a few inches from the sensor
Serial.println("medium");
break;
case 3:    // your hand is nowhere near the sensor
Serial.println("bright");
break;
}
```

} @]

to:
July 01, 2009, at 07:59 PM by Tom Igoe -
Changed line 48 from:
``` http://www.arduino.cc/en/Tutorial/Loop
```
to:
``` http://www.arduino.cc/en/Tutorial/SwitchCase
```
July 01, 2009, at 07:29 PM by Tom Igoe -
Changed lines 3-4 from:

to:

## Switch (case) Statement

### used with sensor input

July 01, 2009, at 07:29 PM by Tom Igoe -

Examples > Control Structures

## Switch (case) Statement (sensor input)

An if statement allows you to choose between two discrete options, TRUE or FALSE. When there are more than two options, you can use multiple if statements, or you can use the switch statement. Switch allows you to choose between several discrete options. This tutorial shows you how to use it to switch between four desired states of a photo resistor: really dark, dim, medium, and bright.

The sketch first reads the photoresistor. Then it uses the `map()` function to map its output to one of four values: 0, 1, 2, or 3. Finally, it uses the `switch()` statement to print one of four messages back to the computer depending on which of the four values is returned.

### Circuit

The photoresistor is connected to analog in pin 0 using a voltage divider circuit. A 10Kilohm resistor makes up the other side of the voltage divider, running from analog in 0 to ground. The `analogRead()` function returns a range of about 0 to 600 from this circuit in a reasonably lit indoor space.

click the image to enlarge

Schematic:

click the image to enlarge

### Code

```/*
Switch statement

Demonstrates the use of a switch statement.  The switch
statement allows you to choose from among a set of discrete values
of a variable.  It's like a series of if statements.

To see this sketch in action, but the board and sensor in a well-lit
down over the sensor.

The circuit:

created 1 Jul 2009
by Tom Igoe

http://www.arduino.cc/en/Tutorial/Loop
*/

// these constants won't change:
const int sensorMin = 0;      // sensor minimum, discovered through experiment
const int sensorMax = 600;    // sensor maximum, discovered through experiment

void setup() {
// initialize serial communication:
Serial.begin(9600);
}

void loop() {
// map the sensor range to a range of four options:
int range = map(sensorReading, sensorMin, sensorMax, 0, 3);

// do something different depending on the
// range value:
switch (range) {
case 0:    // your hand is on the sensor
Serial.println("dark");
break;
case 1:    // your hand is close to the sensor
Serial.println("dim");
break;
case 2:    // your hand is a few inches from the sensor
Serial.println("medium");
break;
case 3:    // your hand is nowhere near the sensor
Serial.println("bright");
break;
}

}

```