lejos.hardware.device.tetrix.TetrixControllerFactory Maven / Gradle / Ivy
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package lejos.hardware.device.tetrix;
import lejos.hardware.port.Port;
import lejos.hardware.sensor.I2CSensor;
/**
* HiTechnic Tetrix Motor and Servo Controller factory class used to provide Motor and Servo controller abstractions.
* These are then used
* to obtain motor and servo instances respectively. These abstraction classes are TetrixMotorController and
* TetrixServoController.
*
* Motor and servo controllers are enumerated starting at the controller connected to one of the NXT's sensor ports and then
* working outwards along the daisy chain. 4 controllers can be daisy-chained, with a mixture of servo and/or motor controllers.
* No other sensors can be connected to the daisy-chain.
*
*
Code Example:
*
* // Instantiate the factory and get a Motor and servo controller. We assume that there is one of
* // each daisy-chained.
* TetrixControllerFactory cf = new TetrixControllerFactory(SensorPort.S1);
* TetrixMotorController mc = cf.newMotorController();
* TetrixServoController sc = cf.newServoController();
*
* // Display the voltage from the motor controller
* System.out.println("v=" + mc.getVoltage());'
*
* // Get an encoder motor instance. The physical motor (with encoder) is connected to the Motor 2 terminals on the controller
* TetrixEncoderMotor mot1 = mc.getEncoderMotor(TetrixMotorController.MOTOR_2);
*
* // Start the motor
* mot1.forward();
*
*
* @author Kirk P. Thompson
* @see TetrixMotorController
* @see TetrixServoController
*/
public class TetrixControllerFactory {
/**
* Position 1 (nearest to the NXT) in the daisy chain. Use this if only one controller.
*/
public static final int DAISY_CHAIN_POSITION_1 = 2;
/**
* Position 2 in the daisy chain.
*/
public static final int DAISY_CHAIN_POSITION_2 = 4;
/**
* Position 3 in the daisy chain.
*/
public static final int DAISY_CHAIN_POSITION_3 = 6;
/**
* Position 3 (furthest from the NXT)in the daisy chain.
*/
public static final int DAISY_CHAIN_POSITION_4 = 8;
private static final int MAX_CHAINED_CONTROLLERS=4;
static final String TETRIX_VENDOR_ID = "HiTechnc";
static final String TETRIX_MOTORCON_PRODUCT_ID = "MotorCon";
static final String TETRIX_SERVOCON_PRODUCT_ID = "ServoCon";
private int currentMotorIndex=0;
private int currentServoIndex=0;
private Port port;
private Finder finder;
/**
* Instantiate a TetrixControllerFactory using the specified NXT sensor port.
* @param port The NXT sensor port the Tetrix controller is connected to
*/
public TetrixControllerFactory(Port port){
this.port=port;
finder = new Finder(port);
}
private class Finder extends I2CSensor {
Finder(Port port) {
super(port);
}
/**
* @param i where to start searching index-wise
* @param product the product ID string
* @return the index the product ID was found. -1 if not found or outside MAX_CHAINED_CONTROLLERS bounds
*/
private int findProduct(int i, String product){
if (i<0 || i>=MAX_CHAINED_CONTROLLERS) return -1;
for (;i
* Successive controllers in a daisy-chain logically go "outwards" from the controller closest to the NXT as #1 to #4 for each controller
* in the chain. Once a specific, logical controller has been retrieved using this method, it cannot be retrieved again.
*
* A combination of Servo and Motor controllers can be daisy-chained.
* @return The next available TetrixMotorController instance.
* @throws IllegalStateException If no more motor controllers can be returned. If there are no motor controllers
* in the daisy-chain, this exception is also thrown.
* @see #newServoController
*/
public TetrixMotorController newMotorController()
{
this.currentMotorIndex = finder.findProduct(this.currentMotorIndex, TETRIX_MOTORCON_PRODUCT_ID);
if (this.currentMotorIndex<0) throw new IllegalStateException("no motor controllers available");
TetrixMotorController mc = new TetrixMotorController(finder.getPort(), (this.currentMotorIndex + 1) * 2);
this.currentMotorIndex++;
return mc;
}
/**
* Get the next available Tetrix Servo controller. Motor controllers in the daisy-chain (if any) are skipped in the search.
*
* Successive controllers in a daisy-chain logically go "outwards" from the controller closest to the NXT as #1 to #4 for each controller
* in the chain. Once a specific, logical controller has been retrieved using this method, it cannot be retrieved again.
*
* A combination of Servo and Motor controllers can be daisy-chained.
* @return The next available TetrixServoController instance.
* @throws IllegalStateException If no more servo controllers can be returned. If there are no servo controllers
* in the daisy-chain, this exception is also thrown.
* @see #newMotorController
*/
public TetrixServoController newServoController()
{
this.currentServoIndex = finder.findProduct(this.currentServoIndex, TETRIX_SERVOCON_PRODUCT_ID);
if (this.currentServoIndex<0) throw new IllegalStateException("no servo controllers available");
TetrixServoController sc = new TetrixServoController(finder.getPort(), (this.currentServoIndex + 1) * 2);
this.currentServoIndex++;
return sc;
}
}