Package com.oracle.deviceaccess.adc

Interfaces and classes for reading analog inputs using an Analog to Digital Converter (ADC).

See: Description

Interface Summary

Interface	Description
AcquisitionListener	The AcquisitionListener interface defines methods for getting notified of the availability of sampled input values.
ADCChannel	The ADCChannel interface provides methods for controlling an ADC (Analog to Digital Converter) channel.
MonitoringListener	The MonitoringListener interface defines methods for getting notified of ADC channel under- and over-threshold input value conditions.

Class Summary

Class	Description
AcquisitionEvent	The AcquisitionEvent class encapsulates ADC channel input acquisition conditions.
ADCChannelConfig	The ADCChannelConfig class encapsulates the hardware addressing information, and static and dynamic configuration parameters of an ADC channel.
MonitoringEvent	The MonitoringEvent class encapsulates ADC channel under- and over-threshold value conditions.

Exception Summary

Exception	Description
InvalidInputSamplingRateException	Thrown by an instance of ADCChannel in case the requested sampling rate is higher than the maximum input sampling rate the ADC device can support.

Package com.oracle.deviceaccess.adc Description

Interfaces and classes for reading analog inputs using an Analog to Digital Converter (ADC).

One ADC converter can have several channels. Each channel can sample a continuous input voltage and convert it to a numerical value.

In order to access and control a specific ADC channel, an application should first open and obtain an ADCChannel instance for the ADC channel the application wants to access and control, using its numerical ID, name, type (interface) and/or properties:

Using its ID

 ADCChannel channel = (ADCChannel) PeripheralManager.open(8);
 

Using its name and interface

 ADCChannel channel = (ADCChannel) PeripheralManager.open("TEMPERATURE", ADCChannel.class, null);
 

Once the peripheral opened, the application can read or monitor sampled input values using methods of the ADCChannel interface such as the getValue method.

 int temp = channel.getValue();
 

When done, the application should call the ADCChannel.close() method to release ADC channel.

 channel.close();
 

The following sample codes give examples of using the ADC API:

 class ADCAcquisition implements AcquisitionListener {
 
     private ADCChannel channel = null;
 
     public void start(int channelID) throws IOException, PeripheralNotAvailableException, PeripheralNotFoundException {
         channel = (ADCChannel) PeripheralManager.open(channelID);
         channel.setSamplingInterval(100); // every 100 milliseconds
         int[] values = new int[10];
         channel.startAcquisition(values, 0, values.length, this);
     }
 
     public void inputAcquired(AcquisitionEvent event) {
         for (int i = 0; i < event.getCount(); i++) {
             int value = event.getValues()[event.getOffset() + i];
             // Handle value...
         }
     }
 
     public void stop() throws IOException, PeripheralNotAvailableException {
         if (channel != null) {
             channel.stopAcquisition();
             channel.close();
         }
     }
 }
 

 class ADCThreshold implements MonitoringListener {
 
     private ADCChannel channel = null;
 
     public void start(int channelID, int low, int high) throws IOException, PeripheralNotAvailableException,
             PeripheralNotFoundException {
         channel = (ADCChannel) PeripheralManager.open(channelID);
         channel.setSamplingInterval(100); // every 100 milliseconds
         channel.startMonitoring(low, high, this);
     }
 
     public void thresholdReached(MonitoringEvent event) {
         if (event.getType() == MonitoringEvent.OUT_OF_RANGE) {
             int value = event.getValue();
             // Handle condition...
         }
     }
 
     public void stop() throws IOException, PeripheralNotAvailableException {
         if (channel != null) {
             channel.stopMonitoring();
             channel.close();
         }
     }
 }
 

Because of performance issue, procedures handling analog inputs, and especially event listeners, should be implemented to be as fast as possible.

Security

ADC channels are opened by invoking one of the com.oracle.deviceaccess.PeripheralManager.open methods. The "com.oracle.deviceaccess.adc" permission allows access to be granted to ADC channels as a whole.