text: /*
   * Copyright (c) 2010, Swedish Institute of Computer Science.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the Institute nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * This file is part of the Contiki operating system.
   *
   * $Id: sky-sensors.c,v 1.3 2010/08/25 19:30:53 nifi Exp $
   *
   * -----------------------------------------------------------------
   *
   * Author  : Joakim Eriksson
   * Created : 2010-02-02
   * Updated : $Date: 2010/08/25 19:30:53 $
   *           $Revision: 1.3 $
   */
  #include "contiki.h"
  #include "lib/sensors.h"
  #include <io.h>
  
  #define ADC12MCTL_NO(adcno) ((unsigned char *) ADC12MCTL0_)[adcno]
  
  static uint16_t adc_on;
  static uint16_t ready;
  /*---------------------------------------------------------------------------*/
  static CC_INLINE void
  start(void)
  {
    uint16_t c, last;
  
    /* Set up the ADC. */
    P6DIR = 0xff;
    P6OUT = 0x00;
  
    /* Setup ADC12, ref., sampling time */
    /* XXX Note according to the specification a minimum of 17 ms should
       be allowed after turn on of the internal reference generator. */
    ADC12CTL0 = REF2_5V + SHT0_6 + SHT1_6 + MSC + REFON;
    /* Use sampling timer, repeat-sequence-of-channels */
    ADC12CTL1 = SHP + CONSEQ_3;
  
    last = 15;
    for(c = 0; c < 16; c++) {
      /* Clear all end-of-sequences */
      ADC12MCTL_NO(c) &= ~EOS;
      if(adc_on & (1 << c)) {
        if(last == 15) {
          /* Set new start of sequence to lowest active memory holder */
          ADC12CTL1 |= (c * CSTARTADD_1);
        }
        last = c;
      }
    }
  
    /* Set highest end-of-sequence. */
    ADC12MCTL_NO(last) |= EOS;
  
    ADC12CTL0 |= ADC12ON;
    ADC12CTL0 |= ENC;                   /* enable conversion */
    ADC12CTL0 |= ADC12SC;               /* sample & convert */
  }
  /*---------------------------------------------------------------------------*/
  static CC_INLINE void
  stop(void)
  {
    /* stop converting immediately, turn off reference voltage, etc. */
  
    ADC12CTL0 &= ~ENC;
    /* need to remove CONSEQ_3 if not EOS is configured */
    ADC12CTL1 &= ~CONSEQ_3;
  
    /* wait for conversion to stop */
    while(ADC12CTL1 & ADC12BUSY);
  
    /* clear any pending interrupts */
    ADC12IFG = 0;
  }
  /*---------------------------------------------------------------------------*/
  int
  sky_sensors_status(uint16_t input, int type)
  {
    if(type == SENSORS_ACTIVE) {
      return (adc_on & input) == input;
    }
    if(type == SENSORS_READY) {
      ready |= ADC12IFG & adc_on & input;
      return (ready & adc_on & input) == input;
    }
    return 0;
  }
  /*---------------------------------------------------------------------------*/
  int
  sky_sensors_configure(uint16_t input, uint8_t ref, int type, int value)
  {
    uint16_t c;
  
    if(type == SENSORS_ACTIVE) {
      stop();
  
      if(value) {
        adc_on |= input;
        P6SEL |= input & 0xff;
  
        /* Set ADC config */
        for(c = 0; c < 16; c++) {
          if(input & (1 << c)) {
            ADC12MCTL_NO(c) = (c * INCH_1) | ref;
          }
        }
  
      } else {
        adc_on &= ~input;
        ready &= ~input;
        P6SEL &= ~(input & 0xff);
      }
  
      if(adc_on == 0) {
        P6DIR = 0x00;
        P6SEL = 0x00;
  
        /* Turn off ADC and internal reference generator */
        ADC12CTL0 = 0;
        ADC12CTL1 = 0;
      } else {
        start();
      }
      return 1;
    }
    return 0;
  }
  /*---------------------------------------------------------------------------*/
  