a2d.c

/*! \file a2d.c \brief Analog-to-digital Converter Driver for ADuC7000. */
//*****************************************************************************
//
// File Name    : 'a2d.c'
// Title        : Analog-to-digital Converter Driver for ADuC7000
// Author       : Pascal Stang - Copyright (C) 2005
// Created      : 2/5/2005
// Revised      : 2/5/2005
// Version      : 0.1
// Target MCU   : Analog Devices ADuC7000 ARM Series
// Editor Tabs  : 4
//
// This code is distributed under the GNU Public License
//      which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************

#include "aduc7026.h"

#include "global.h"
#include "a2d.h"

// functions
void a2dInit(void)
{
    #define ADCENCONV           (1<<7)
    #define ADCBUSY             (1<<6)
    #define ADCPWR              (1<<5)
    #define ADCMODE_SE          (0x00<<3)
    #define ADCMODE_DIFF        (0x01<<3)
    #define ADCMODE_PDIFF       (0x02<<3)
    #define ADCMODE_MASK        (0x03<<3)
    #define ADCCONV_SINGLE      (0x03)
    #define ADCCONV_CONT        (0x04)

    // set ADC to ON
    ADCCON |= ADCPWR;

    // select reference
    REFCON = 0x01;  // internal 2.5V reference
}

int a2dConvert(int channel)
{
    // set conversion mode to single-ended
    ADCCON &= ~ADCMODE_MASK;
    ADCCON |= ADCMODE_SE;
    // set channel for conversion
    ADCCP = channel;
    // start conversion
    ADCCON |= ADCENCONV | ADCCONV_SINGLE;
    // wait until complete
    while(!ADCSTA);
    // return result
    return ADCDAT>>16;
}

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