contiki/platform/sky/dev/sky-sensors.c

153 lines
4.5 KiB
C

/*
* 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.
*
*
* -----------------------------------------------------------------
*
* 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"
#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;
}
/*---------------------------------------------------------------------------*/