HCSR04UsingEvents (diozero - Core 1.3.2 API)

java.lang.Object
- com.diozero.devices.sandpit.HCSR04UsingEvents

All Implemented Interfaces:

DeviceInterface, DeviceEventConsumer<DigitalInputEvent>, DistanceSensorInterface, SensorInterface, AutoCloseable, Consumer<DigitalInputEvent>
```
public class HCSR04UsingEvents
extends Object
implements DistanceSensorInterface, DeviceEventConsumer<DigitalInputEvent>
```
Note this version doesn't work as well as the polling-based HCSR04 version. User's manual: https://docs.google.com/document/d/1Y-yZnNhMYy7rwhAgyL_pfa39RsB-x2qR4vP8saG73rE/edit# Product specification: http://www.micropik.com/PDF/HCSR04.pdf Provides 2cm - 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. You only need to supply a short 10uS pulse to trigger input to start the ranging, and then the module will send out an 8 cycle burst of ultrasound at 40 kHz and raise its echo. The Echo is a distance object that is pulse width and the range in proportion. We suggest to use over 60ms measurement cycle, in order to prevent trigger signal to the echo signal.

Constructor Summary

Constructors
Constructor Description

HCSR04UsingEvents(int triggerGpioNum, int echoGpioNum)
Initialise GPIO to echo and trigger pins

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`accept(DigitalInputEvent event)`
`void`	`close()`	Free device GPIOs
`float`	`getDistanceCm()`	Send a pulse to HCSR04 and compute the echo to obtain distance

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.function.Consumer
andThen

- Constructor Detail
  - HCSR04UsingEvents
```
public HCSR04UsingEvents(int triggerGpioNum,
                         int echoGpioNum)
                  throws RuntimeIOException
```
    Initialise GPIO to echo and trigger pins
    
    Parameters:
    
    triggerGpioNum - GPIO connected to the HC-SR04 trigger pin
    
    echoGpioNum - GPIO connected to the HC-SR04 echo pin
    
    Throws:
    
    RuntimeIOException - if an I/O error occurs
- Method Detail
  - getDistanceCm
```
public float getDistanceCm()
                    throws RuntimeIOException
```
    Send a pulse to HCSR04 and compute the echo to obtain distance
    
    Specified by:
    
    getDistanceCm in interface DistanceSensorInterface
    
    Returns:
    
    distance in cm
    
    Throws:
    
    RuntimeIOException - if an I/O error occurs
  - close
```
public void close()
```
    Free device GPIOs
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface DeviceInterface
  - accept
```
public void accept(DigitalInputEvent event)
```
    Specified by:
    
    accept in interface Consumer<DigitalInputEvent>