com.pi4j.gpio.extension.base

Class AdcGpioProviderBase

java.lang.Object

com.pi4j.io.gpio.GpioProviderBase

com.pi4j.gpio.extension.base.AdcGpioProviderBase

All Implemented Interfaces:

AdcGpioProvider, GpioProvider

Direct Known Subclasses:

MCP3424GpioProvider, MCP3x0xGpioProvider

public abstract class AdcGpioProviderBase
extends GpioProviderBase
implements AdcGpioProvider

This base GPIO provider defined the required interfaces and implements the base functionality for ADC (analog to digital) expansion chips as native Pi4J GPIO pins.

Author:

Robert Savage

Field Summary

Fields

Modifier and Type	Field and Description
protected Pin[]	allPins
protected int	conversionDelay
protected com.pi4j.gpio.extension.base.AdcGpioProviderBase.ADCMonitor	monitor
protected int	monitorInterval
protected double[]	threshold

Fields inherited from class com.pi4j.io.gpio.GpioProviderBase

cache, DEFAULT_CACHE_SIZE, isshutdown, listeners

Fields inherited from interface com.pi4j.gpio.extension.base.AdcGpioProvider

DEFAULT_MONITOR_INTERVAL, DEFAULT_THRESHOLD, INVALID_VALUE, MIN_MONITOR_INTERVAL

Constructor Summary

Constructors

Constructor and Description
AdcGpioProviderBase(Pin[] pins) Default Constructor

Method Summary

Modifier and Type	Method and Description
double	getEventThreshold(GpioPinAnalogInput pin) Get the event threshold value for a given analog input pin.
double	getEventThreshold(Pin pin) Get the event threshold value for a given analog input pin.
double	getImmediateValue(GpioPinAnalogInput pin) This method will perform an immediate data acquisition directly to the ADC chip to get the requested pin's input conversion value.
abstract double	getImmediateValue(Pin pin) This method will perform an immediate data acquisition directly to the ADC chip to get the requested pin's input conversion value.
boolean	getMonitorEnabled() Get the background monitoring thread's enabled state.
int	getMonitorInterval() Get the background monitoring thread's rate of data acquisition.
float	getPercentValue(GpioPinAnalogInput pin) Get the current value in a percentage of the available range instead of a raw value.
float	getPercentValue(Pin pin) Get the current value in a percentage of the available range instead of a raw value.
double	getValue(Pin pin) Get the requested analog input pin's conversion value.
void	setEventThreshold(double threshold, GpioPinAnalogInput... pin) Set the event threshold value for a given analog input pin.
void	setEventThreshold(double threshold, Pin... pin) Set the event threshold value for a given analog input pin.
void	setMonitorEnabled(boolean enabled) Set the background monitoring thread's enabled state.
void	setMonitorInterval(int monitorInterval) Change the background monitoring thread's rate of data acquisition.
void	shutdown() This method is used by the framework to shutdown the background monitoring thread if needed when the program exits.

Methods inherited from class com.pi4j.io.gpio.GpioProviderBase

addListener, dispatchPinAnalogValueChangeEvent, dispatchPinDigitalStateChangeEvent, export, export, getMode, getName, getPinCache, getPullResistance, getPwm, getState, hasPin, isExported, isShutdown, removeAllListeners, removeListener, setMode, setPullResistance, setPwm, setPwmRange, setState, setValue, unexport

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.pi4j.gpio.extension.base.AdcGpioProvider

getMaxSupportedValue, getMinSupportedValue

Methods inherited from interface com.pi4j.io.gpio.GpioProvider

addListener, export, export, getMode, getName, getPullResistance, getPwm, getState, hasPin, isExported, isShutdown, removeAllListeners, removeListener, setMode, setPullResistance, setPwm, setPwmRange, setState, setValue, unexport

Field Detail

monitor

protected com.pi4j.gpio.extension.base.AdcGpioProviderBase.ADCMonitor monitor

conversionDelay

protected int conversionDelay

monitorInterval

protected int monitorInterval

allPins

protected Pin[] allPins

threshold

protected double[] threshold

Constructor Detail

AdcGpioProviderBase

public AdcGpioProviderBase(Pin[] pins)

Default Constructor

Parameters:

pins - the collection of all GPIO pins used with this ADC provider implementation

Method Detail

getValue

public double getValue(Pin pin)

Get the requested analog input pin's conversion value. If you have the background monitoring thread enabled, then this function will return the last cached value. If you have the background monitoring thread disabled, then this function will will perform an immediate data acquisition directly to the ADC chip to get the requested pin's input conversion value. (via getImmediateValue())

Specified by:

getValue in interface GpioProvider

Overrides:

getValue in class GpioProviderBase

Parameters:

pin - to get conversion values for

Returns:

analog input pin conversion value (10-bit: 0 to 1023)

getPercentValue

public float getPercentValue(Pin pin)

Get the current value in a percentage of the available range instead of a raw value.

Specified by:

getPercentValue in interface AdcGpioProvider

Returns:

percentage value between 0 and 100.

getPercentValue

public float getPercentValue(GpioPinAnalogInput pin)

Get the current value in a percentage of the available range instead of a raw value.

Specified by:

getPercentValue in interface AdcGpioProvider

Returns:

percentage value between 0 and 100.

getImmediateValue

public double getImmediateValue(GpioPinAnalogInput pin)
                         throws IOException

This method will perform an immediate data acquisition directly to the ADC chip to get the requested pin's input conversion value.

Specified by:

getImmediateValue in interface AdcGpioProvider

Parameters:

pin - requested input pin to acquire conversion value

Returns:

conversion value for requested analog input pin

Throws:

IOException

shutdown

public void shutdown()

This method is used by the framework to shutdown the background monitoring thread if needed when the program exits.

Specified by:

shutdown in interface GpioProvider

Overrides:

shutdown in class GpioProviderBase

getEventThreshold

public double getEventThreshold(Pin pin)

Get the event threshold value for a given analog input pin. The event threshold value determines how much change in the analog input pin's conversion value must occur before the framework issues an analog input pin change event. A threshold is necessary to prevent a significant number of analog input change events from getting propagated and dispatched for input values that may have an expected range of drift. see the DEFAULT_THRESHOLD constant for the default threshold value.

Specified by:

getEventThreshold in interface AdcGpioProvider

Parameters:

pin - analog input pin

Returns:

event threshold value for requested analog input pin

getEventThreshold

public double getEventThreshold(GpioPinAnalogInput pin)

Get the event threshold value for a given analog input pin. The event threshold value determines how much change in the analog input pin's conversion value must occur before the framework issues an analog input pin change event. A threshold is necessary to prevent a significant number of analog input change events from getting propagated and dispatched for input values that may have an expected range of drift. see the DEFAULT_THRESHOLD constant for the default threshold value.

Specified by:

getEventThreshold in interface AdcGpioProvider

Parameters:

pin - analog input pin

Returns:

event threshold value for requested analog input pin

setEventThreshold

public void setEventThreshold(double threshold,
                              Pin... pin)

Set the event threshold value for a given analog input pin. The event threshold value determines how much change in the analog input pin's conversion value must occur before the framework issues an analog input pin change event. A threshold is necessary to prevent a significant number of analog input change events from getting propagated and dispatched for input values that may have an expected range of drift. see the DEFAULT_THRESHOLD constant for the default threshold value.

Specified by:

setEventThreshold in interface AdcGpioProvider

Parameters:

threshold - threshold value for requested analog input pin

pin - analog input pin (vararg, one or more inputs can be defined.)

setEventThreshold

public void setEventThreshold(double threshold,
                              GpioPinAnalogInput... pin)

Set the event threshold value for a given analog input pin. The event threshold value determines how much change in the analog input pin's conversion value must occur before the framework issues an analog input pin change event. A threshold is necessary to prevent a significant number of analog input change events from getting propagated and dispatched for input values that may have an expected range of drift. see the DEFAULT_THRESHOLD constant for the default threshold value.

Specified by:

setEventThreshold in interface AdcGpioProvider

Parameters:

threshold - threshold value for requested analog input pin.

pin - analog input pin (vararg, one or more inputs can be defined.)

getMonitorInterval

public int getMonitorInterval()

Get the background monitoring thread's rate of data acquisition. (in milliseconds) The default interval is 100 milliseconds. The minimum supported interval is 50 milliseconds.

Specified by:

getMonitorInterval in interface AdcGpioProvider

Returns:

monitoring interval in milliseconds

setMonitorInterval

public void setMonitorInterval(int monitorInterval)

Change the background monitoring thread's rate of data acquisition. (in milliseconds) The default interval is 100 milliseconds. The minimum supported interval is 50 milliseconds.

Specified by:

setMonitorInterval in interface AdcGpioProvider

Parameters:

monitorInterval -

getMonitorEnabled

public boolean getMonitorEnabled()

Get the background monitoring thread's enabled state.

Specified by:

getMonitorEnabled in interface AdcGpioProvider

Returns:

monitoring enabled or disabled state

setMonitorEnabled

public void setMonitorEnabled(boolean enabled)

Set the background monitoring thread's enabled state.

Specified by:

setMonitorEnabled in interface AdcGpioProvider

Parameters:

enabled - monitoring enabled or disabled state

getImmediateValue

public abstract double getImmediateValue(Pin pin)
                                  throws IOException

This method will perform an immediate data acquisition directly to the ADC chip to get the requested pin's input conversion value.

Specified by:

getImmediateValue in interface AdcGpioProvider

Parameters:

pin - requested input pin to acquire conversion value

Returns:

conversion value for requested analog input pin

Throws:

IOException