/*
This file is part of JOP, the Java Optimized Processor
see <http://www.jopdesign.com/>
Copyright (C) 2007, Peter Hilber and Alexander Dejaco
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package lego.lib;
import com.jopdesign.sys.*;
/**
* Provides access to diagnostic LEDs (LED0-LED3).
* @author Peter Hilber (peter.hilber@student.tuwien.ac.at)
*
*/
public class Leds
{
public static final int IO_LEDS = Const.IO_LEGO + 0;
public static final int LED_COUNT = 4;
protected static int value;
/**
* Turns the LED on and off several times a second (if called that often).<br/>
* The LED is set if the 18^th bit of us is on.
* Therefore, the update has to be called at least 8 times a second.
* @param index 0-3.
*/
public static final void blinkUpdate(int index)
{
setLed(index, (Native.rd(Const.IO_US_CNT) & 0x40000) != 0);
}
/**
* Sets diagnostic LEDs.
* @param state LEDs 0-3 state is set by the corresponding bits.
* All other bits are ignored.
*/
public static final void setLeds(int state)
{
value = state;
Native.wr(state, IO_LEDS);
}
/**
* Returns the state of the diagnostic LEDs.
* @return State of the LEDs 0-3 in the corresponding bit.
* All other bits are set to zero.
*/
public static final int getLeds()
{
return value;
}
/**
* Returns the state of a diagnostic LED.
* @param index 0-3.
*/
public static final boolean getLed(int index)
{
return ((value >> index) & 1) != 0;
}
/**
* Sets the state of a diagnostic LED.
* @param index 0-3.
* @param on
*/
public static final void setLed(int index, boolean on)
{
setLeds((getLeds() & ~(1<<index)) | ((on?1:0)<<index));
}
}