msp-adc.c

MANTIS是由科罗拉多大学开发的传感器网络嵌入式操作系统。 这是mantis的0.9.5版本的源码。

//  This file is part of MANTIS OS, Operating System
//  See http://mantis.cs.colorado.edu/
//
//  Copyright (C) 2003,2004,2005 University of Colorado, Boulder
//
//  This program is free software; you can redistribute it and/or
//  modify it under the terms of the mos license (see file LICENSE)

/*
  Project Mantis
  File:   msp-adc.c
  Author: Charles Gruenwald III
  Date:   05-20-05

  This file implements the lowest level control of the analog to digital
  conversion system on the msp430x16x device.
*/

#include "mos.h"

#ifdef PLATFORM_TELOSB

#include "msp-adc.h"
#include "dev.h"
#include "mutex.h"
#include "sem.h"

uint8_t adc_channel;

void adc_set_channel(uint8_t ch)
{
   uint8_t addr = 0;
   //set the addr where conversion result will reside
   ADC12CTL1 |= ((addr & 0x0F) << 11);

   //set the addr to read from the corresponding channel
   ADC12MCTL0 |= (ch & 0x0F);

}

uint16_t adc_get_conversion16(uint8_t ch)
{

   ADC12CTL0 &= ~ENC;

   adc_on();

   adc_set_channel(ch);
   
   //set source of sampling signal (SAMPCON) to be the output of
   //the sampling timer
   ADC12CTL1 |= SHP;

   //start the conversion
   ADC12CTL0 |= ENC | ADC12SC;

   //polling wait for conversion to complete
   while(ADC12CTL1 & ADC12BUSY);

   uint16_t sample = ADC12MEM0;
   return sample;
}


#endif