// $Id: SenseTaskM.nc,v 1.4 2004/05/30 23:34:56 jpolastre Exp $/*									tab:4 * "Copyright (c) 2000-2003 The Regents of the University  of California.   * All rights reserved. * * Permission to use, copy, modify, and distribute this software and its * documentation for any purpose, without fee, and without written agreement is * hereby granted, provided that the above copyright notice, the following * two paragraphs and the author appear in all copies of this software. *  * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. *  * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS." * * Copyright (c) 2002-2003 Intel Corporation * All rights reserved. * * This file is distributed under the terms in the attached INTEL-LICENSE      * file. If you do not find these files, copies can be found by writing to * Intel Research Berkeley, 2150 Shattuck Avenue, Suite 1300, Berkeley, CA,  * 94704.  Attention:  Intel License Inquiry. *//*  * Authors:  David Culler,  Su Ping   *           Intel Research Berkeley Lab * *//** * Implementation for SenseTask application.   * * When the timer fires, this application reads sensor data, posts * a task that averages the sensor readings, and displays the highest  * 3 bits of the average to the LEDs. *  * @author David Culler * @author Su Ping * @author Intel Research Berkeley Lab **/module SenseTaskM {  provides {    interface StdControl;  }  uses {    interface Timer;    interface ADC;    interface Leds;  }}implementation {  enum {    log2size = 3,		// log2 of buffer size    size=1 << log2size,		// Circular buffer size    sizemask=size - 1,		// bit mask  };  // declare module static variables here  int8_t head;     // index to the head of the circular buffer  int16_t rdata[size];  // circular buffer  /**   * Module scoped method. Save sensor data into circular buffer.   *   * @return returns void   **/   inline void putdata(int16_t val)  {    int16_t p;    atomic      {	p = head;	head = (p+1) & sizemask;	rdata[p] = val;      }  }  /**    * Module scoped method.  Displays the lowest 3 bits to the LEDs,   * with RED being the most signficant and YELLOW being the least significant.   *   * @return returns <code>SUCCESS</code>   **/  // display is a module static function  result_t display(uint16_t value)  {      if (value &1) call Leds.yellowOn();      else call Leds.yellowOff();      if (value &2) call Leds.greenOn();      else call Leds.greenOff();      if (value &4) call Leds.redOn();      else call Leds.redOff();      return SUCCESS;  }  /**   * Module task.  Process sensor reading, compute the average, and   * display it.   * @return returns void   **/  task void processData()   {     int16_t i, sum=0;     atomic        for (i=0; i<size; i++)	 sum += (rdata[i] >> 7);     display(sum >> log2size);  }  /**   * Initialize the component. Initialize Leds   *    * @return returns <code>SUCCESS</code> or <code>FAILED</code>   **/  command result_t StdControl.init() {    atomic head =0;    return call Leds.init();  }  /**   * Starts the timer.   *    * @return The value of calling <tt>Timer.start()</tt>.   **/  command result_t StdControl.start() {    return call Timer.start(TIMER_REPEAT, 500);  }  /**   * Stops the timer.   *   * @return The value of calling <tt>Timer.stop()</tt>.   **/  command result_t StdControl.stop() {    return call Timer.stop();  }  /**   * Read sensor data in response to the <code>Timer.fired</code> event.     *   * @return The value of calling <tt>ADC.getData()</tt>.   **/  event result_t Timer.fired() {    return call ADC.getData();  }  /**   * In response to <code>ADC.dataReady</code>, store sensor data    * and post task for averaging.   * @return returns <code>SUCCESS</code>   **/  async event result_t ADC.dataReady(uint16_t data) {    putdata(data);    post processData();    return SUCCESS;  }}