/* ---------------------------------------------------------------------------
 * power.c - v0.1                                       (c) 2007 Micro-key bv
 * ---------------------------------------------------------------------------
 * Micro-key bv
 * Industrieweg 28, 9804 TG Noordhorn
 * Postbus 92, 9800 AB Zuidhorn
 * The Netherlands
 * Tel: +31 594 503020
 * Fax: +31 594 505825
 * Email: support@microkey.nl  
 * Web: www.microkey.nl
 * ---------------------------------------------------------------------------
 * Description: Checks for power supply
 * ---------------------------------------------------------------------------
 * Version(s):  0.1, 28-11-2007, fvds.
 *                   Creation.
 * ---------------------------------------------------------------------------
 */

/* ---------------------------------------------------------------------------
 * System include files
 * ---------------------------------------------------------------------------
 */
#include <stdio.h>
#include <stdlib.h>


/* ---------------------------------------------------------------------------
 * Application include files
 * ---------------------------------------------------------------------------
 */
#include "LPC23xx.h"
#include "types.h"
#include "power.h"

/* FreeRTOS includes */
#include "FreeRTOS.h"

/* ---------------------------------------------------------------------------
 * Local constant and macro definitions
 * ---------------------------------------------------------------------------
 */
#define ADC_INTERRUPT_FLAG  1 /* 1 is interrupt driven, 0 is polling */

#define ADC_OFFSET    0x10
#define ADC_INDEX   4

#define ADC_DONE    0x80000000
#define ADC_OVERRUN   0x40000000
#define ADC_ADINT   0x00010000

#define ADC_NUM     8   /* for LPC23xx */
#define ADC_CLK     1000000   /* set to 1Mhz */

#define VCC_DIVIDER_R1   22000
#define VCC_DIVIDER_R2   19100
#define VCC_DIVIDER_CORR ((VCC_DIVIDER_R2 * 1000) / (VCC_DIVIDER_R1 + VCC_DIVIDER_R2))
#define V24_DIVIDER_R1   33000
#define V24_DIVIDER_R2   3300
#define V24_DIVIDER_CORR ((V24_DIVIDER_R2 * 1000) / (V24_DIVIDER_R1 + V24_DIVIDER_R2))

/* ---------------------------------------------------------------------------
 * Global variable definitions
 * ---------------------------------------------------------------------------
 */

/* ---------------------------------------------------------------------------
 * Local variable definitions
 * ---------------------------------------------------------------------------
 */

/* ---------------------------------------------------------------------------
 * Local function definitions
 * ---------------------------------------------------------------------------
 */
static UINT16 ADC0Read( UINT8 channelNum );
static UINT16 Convert2mV( UINT32 dataRegistry );


void powerInit()
{
    /* Enable CLOCK into ADC controller */
    PCONP |= (1 << 12);
    
    /* all the related pins are set to ADC inputs, AD0.0, 4 and 5 */
    PINSEL1 &= ~0x0000C000;  /* P0.23, A0.0, function 01 */
    PINSEL1 |=  0x00004000;
    PINSEL3 |=  0xC0000000;  /* P1.31, A0.5, function 11 */
    
    AD0CR = ( 0x21 << 0 ) |   /* SEL=1,select channel 0,4 and 5 on ADC0 */
            ( 0 << 8  ) |     /* CLKDIV = Fpclk / 1000000 - 1  => 2.4 MHz */
            ( 1 << 16 ) |     /* BURST = 0, no BURST, software controlled */
            ( 0 << 17 ) |     /* CLKS = 0, 11 clocks/10 bits */
            ( 1 << 21 ) |     /* PDN = 1, normal operation */
            ( 0 << 22 ) |     /* TEST1:0 = 00 */
            ( 0 << 24 ) |     /* START = 0 A/D conversion stops */
            ( 0 << 27 );      /* EDGE = 0 (CAP/MAT singal falling,trigger A/D conversion) */
}

UINT16 powerVccVoltage()
{
    UINT32 adcDataRegister;
    UINT32 voltage;
    
    adcDataRegister = AD0DR5;
    voltage = Convert2mV( adcDataRegister );
    
    // Correct voltage divider
    voltage = (voltage * 1000)/VCC_DIVIDER_CORR;
    
    return voltage;
}

UINT16 powerV24Voltage()
{
    UINT32 adcDataRegister;
    UINT32 voltage;
    
    adcDataRegister = AD0DR0;
    voltage = Convert2mV( adcDataRegister );
    
    // Correct voltage divider
    voltage = (voltage * 1000)/V24_DIVIDER_CORR;
    
    return voltage;
}


UINT16 Convert2mV( UINT32 dataRegister )
{
    UINT32 pwrDummy;
    dataRegister = dataRegister >> 6;
    dataRegister = dataRegister & 0x03FF;
    
    // Convert ADC value to voltage (0..1024 -> 0.. 3300 mV)
    dataRegister = (dataRegister * 3300) / (1024);
    pwrDummy = dataRegister;
    
    return (UINT16)dataRegister;
}

UINT16 ADC0Read( UINT8 channelNum )
{
    UINT16 regVal, ADC_Data;

    /* channel number is 0 through 7 */
    if ( channelNum >= ADC_NUM )
        {
        channelNum = 0;   /* reset channel number to 0 */
        }
    AD0CR &= 0xFFFFFF00;
    AD0CR |= (1 << 24) | (1 << channelNum);
    /* switch channel,start A/D convert */

    while ( 1 )     /* wait until end of A/D convert */
        {
        regVal = *(volatile unsigned long *)(AD0_BASE_ADDR + ADC_OFFSET + ADC_INDEX * channelNum);
        /* read result of A/D conversion */
        if ( regVal & ADC_DONE )
            {
            break;
            }
        }

    AD0CR &= 0xF8FFFFFF;  /* stop ADC now */
    if ( regVal & ADC_OVERRUN ) /* save data when it's not overrun, otherwise, return zero */
        {
        return ( 0 );
        }
    ADC_Data = ( regVal >> 6 ) & 0x3FF;
    return ( ADC_Data );  /* return A/D conversion value */
}