upm  1.5.0
Sensor/Actuator repository for libmraa (v1.8.0)
Public Member Functions | Protected Attributes

API for the TTP223 Touch Sensor. More...

Detailed Description

This touch sensor detects when a finger is near the metallic pad by the change in capacitance. It can replace a more traditional push button. The touch sensor can still function when placed under a non-metallic surface like glass or plastic.

ttp223.jpg
// Create the TTP223 touch sensor object using GPIO pin 0
upm::TTP223 touch(0);
// Check whether or not a finger is near the touch sensor and
// print accordingly, waiting one second between readings
while (1) {
if (touch.isPressed()) {
std::cout << touch.name() << " is pressed" << std::endl;
} else {
std::cout << touch.name() << " is not pressed" << std::endl;
}
upm_delay(1);
}
// Delete the touch sensor object

Public Member Functions

 TTP223 (unsigned int pin)
 
 ~TTP223 ()
 
std::string name ()
 
int value ()
 
bool isPressed ()
 
void installISR (mraa::Edge level, void(*isr)(void *), void *arg)
 
void uninstallISR ()
 

Protected Attributes

std::string m_name
 name of this sensor
 
mraa_gpio_context m_gpio
 GPIO pin.
 
bool m_isrInstalled
 

Constructor & Destructor Documentation

◆ TTP223()

TTP223 ( unsigned int  pin)

TTP223 constructor

Parameters
pinGPIO pin where the sensor is connected

◆ ~TTP223()

~TTP223 ( )

TTP223 destructor

Member Function Documentation

◆ name()

std::string name ( )

Returns the name of this sensor

Returns
Name of this sensor

◆ value()

int value ( )

Gets the value from the GPIO pin

Returns
Value from the GPIO pin
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◆ isPressed()

bool isPressed ( )

Determines whether the touch sensor is being touched

Returns
True if touched, false otherwise
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◆ installISR()

void installISR ( mraa::Edge  level,
void(*)(void *)  isr,
void *  arg 
)

Installs an interrupt service routine (ISR) to be called when the button is activated or deactivated.

Parameters
isrPointer to a function to be called on interrupt
argPointer to an object to be supplied as an argument to the ISR.
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◆ uninstallISR()

void uninstallISR ( )

Uninstalls the previously installed ISR

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The documentation for this class was generated from the following files: