ccadc.c File Reference

---

Detailed Description

CC-ADC module.

Application note:

AVR352: Using the CC-ADC

Documentation

For comprehensive code documentation, supported compilers, compiler settings and supported devices see readme.html

Author:

Atmel Corporation: http://www.atmel.com
Support email: avr@atmel.com

Revision

4810

Date

2008-11-04 12:22:27 +0100 (ti, 04 nov 2008)

Copyright (c) 2008, Atmel Corporation 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. The name of ATMEL may not be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY ATMEL "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 EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.

Definition in file ccadc.c.

#include <ioavr.h>
#include "config.h"
#include "ccadc.h"

Include dependency graph for ccadc.c:

Go to the source code of this file.

Data Structures
union	CCADC_conversionFlag_union
Functions
__interrupt void	Ccadc_Acc_ISR (void)
	CC-ADC Accumulated current conversion complete interrupt.
int32_t	CCADC_GetAccResult (void)
	Returns result of an CC-ADC Accumulated Conversion.
int32_t	CCADC_GetIccResult (void)
	Returns result of an CC-ADC Instantaneous Conversion.
uint8_t	CCADC_GetMode (void)
	Provide information whether CC-ADC is in RCC mode of IC/ACC mode.
__interrupt void	Ccadc_Icc_ISR (void)
	CC-ADC instant current conversion complete interrupt.
void	CCADC_Init (CCADC_AccConvPeriod_t accConversionTime, CCADC_RccConvPeriod_t rccSamplingInterval, uint16_t regularCurrentLevel)
	Configuration of the CC-ADC and Regular Current Level.
bool	CCADC_isAccResultReady (void)
	Used to determine if a new CCADC accumulated current result is ready.
bool	CCADC_isIccResultReady (void)
	Used to determine if a new CCADC instant current result is ready.
static void	CCADC_PolarityManager (void)
	Controls when to alter the CC-ADC input polarity.
__interrupt void	Ccadc_Rcc_ISR (void)
	CC-ADC Regular current threshold passed interrupt.
void	CCADC_SetMode (CCADC_modes_t mode)
	Selects mode of operation for the CC-ADC.
Variables
volatile int32_t	CCADC_accResult
volatile int16_t	CCADC_iccResult
union CCADC_conversionFlag_union	CCADC_statusFlags

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Function Documentation

__interrupt void Ccadc_Acc_ISR

(

void

)

CC-ADC Accumulated current conversion complete interrupt.

Definition at line 327 of file ccadc.c.

References CCADC_conversionFlag_union::accResultReady, CCADC_accResult, CCADC_PolarityManager(), and CCADC_statusFlags.

{
    if( CADCSRA & (1<<CADPOL) ){
        CCADC_accResult = - CADAC;
    }else{
        CCADC_accResult = CADAC;
    }
    CCADC_PolarityManager();
    CCADC_statusFlags.accResultReady = true;
}

Here is the call graph for this function:

int32_t CCADC_GetAccResult

(

void

)

Returns result of an CC-ADC Accumulated Conversion.

Returns the 18 bit signed result of an Accumulated Conversion as signed 32-bit. The result is scaled so to use a 24.8 signed fixed point format before it is returned.

Note:

The Bandgap voltage refence must be enabled and calibrated to used the CC-ADC.

Return values:

result

which is returned in a 24.8 signed fixed point format

Definition at line 201 of file ccadc.c.

References CCADC_accResult.

Referenced by main().

{
    int32_t result;
    uint8_t interruptState = __save_interrupt();

    __disable_interrupt();
    result = CCADC_accResult;
    __restore_interrupt(interruptState);

    return result;
}

int32_t CCADC_GetIccResult

(

void

)

Returns result of an CC-ADC Instantaneous Conversion.

Returns the 13 bit signed result of an Instantaneous Conversion as signed 16-bit (since there are no standard datatypes for 13 bit).

Note:

The Bandgap voltage refence must be enabled and calibrated to used the CC-ADC.

Return values:

current

(in mA)

Definition at line 224 of file ccadc.c.

References CCADC_iccResult.

Referenced by main().

{
    int16_t result;
    uint8_t interruptState = __save_interrupt();
    
    __disable_interrupt();
    result = CCADC_iccResult;
    __restore_interrupt(interruptState);
    
    // Scale the 13-bit Icc result to 18-bit like the Acc result.
    return (int32_t)(result * (1<<5));
}

uint8_t CCADC_GetMode

(

void

)

Provide information whether CC-ADC is in RCC mode of IC/ACC mode.

Note:

The Bandgap voltage refence must be enabled and calibrated to used the CC-ADC.

Return values:

mode

[CCADC_RCC, CCADC_IAC (for ICC, ACC or IAC) ]

Definition at line 176 of file ccadc.c.

References CCADC_IAC, and CCADC_RCC.

{
    while( CADCSRA & (1<<CADUB) ){
    }
    
    if( CADCSRA & (1<<CADSE) ){
        return CCADC_RCC;
    }else{
        return CCADC_IAC;
    }
}

__interrupt void Ccadc_Icc_ISR

(

void

)

CC-ADC instant current conversion complete interrupt.

Definition at line 304 of file ccadc.c.

References CCADC_iccResult, CCADC_statusFlags, and CCADC_conversionFlag_union::iccResultReady.

{
    if( CADCSRA & (1<<CADPOL) ){
        CCADC_iccResult = -CADIC;
    }else{
        CCADC_iccResult = CADIC;
    }
    CCADC_statusFlags.iccResultReady = true;
}

void CCADC_Init	(	CCADC_AccConvPeriod_t	accConversionTime,
		CCADC_RccConvPeriod_t	rccSamplingInterval,
		uint16_t	regularCurrentLevel
	)

Configuration of the CC-ADC and Regular Current Level.

Note that the CC-ADC is not started, only configured. The CC-ADC is started by the CCADC_Mode_Select() function.

Note:

The Bandgap voltage refence must be enabled and calibrated to used the CC-ADC.

Parameters:

	accConversionTime	[ACCT_128, ACCT_256, ACCT_512, ACCT_1024]
	rccSamplingInterval	[RSI_256, RSI_512, RSI_1024, RSI_2048]
	regularCurrentLevel	Given in milliAmps

Definition at line 88 of file ccadc.c.

References CCADC_POLARITY_POS, RCC_SCALE, and RCC_STEP_SIZE_mA_SCALED.

Referenced by main().

{ 
    // Set Regular current detection level.
    CADRC = ((regularCurrentLevel<<RCC_SCALE) / RCC_STEP_SIZE_mA_SCALED);

    /* Wait until CC-ADC is ready for configuration change. (wait for
     * synchronization between clock domains to be completed since previous change).
     */
    while( CADCSRA & (1<<CADUB) ){
    }
    
    /* Write CC-ADC settings:
     * - Clear CC-ADC Conversion Time and Regular Current Sampling Interval.\n
     * - select new CC-ADC Conversion Time and Current Sampling Interval.\n
     * - and set the polarity bit accoring the initial state.
     */
    CADCSRA = (CADCSRA & ~( (1<<CADAS1)|(1<<CADAS0)|(1<<CADSI1)|(1<<CADSI0)|(1<<CADPOL) )) |
              ((uint8_t)accConversionTime | (uint8_t)rccSamplingInterval) |
              CCADC_POLARITY_POS;
}

bool CCADC_isAccResultReady

(

void

)

Used to determine if a new CCADC accumulated current result is ready.

Since the internal status flag is also accessed by the interrupt, it is protected by disabling the global interrupt while accessing it.

Return values:

bool

Returns true is new result is ready, otherwise false.

Definition at line 266 of file ccadc.c.

References CCADC_conversionFlag_union::accResultReady, and CCADC_statusFlags.

{
    uint8_t interruptState = __save_interrupt();
    __disable_interrupt();

    bool flagState = CCADC_statusFlags.accResultReady;
    CCADC_statusFlags.accResultReady = false;

    __restore_interrupt( interruptState );
    
    return flagState;
}

bool CCADC_isIccResultReady

(

void

)

Used to determine if a new CCADC instant current result is ready.

Since the internal status flag is also accessed by the interrupt, it is protected by disabling the global interrupt while accessing it.

Return values:

bool

Returns true is new result is ready, otherwise false.

Definition at line 287 of file ccadc.c.

References CCADC_statusFlags, and CCADC_conversionFlag_union::iccResultReady.

{
    uint8_t interruptState = __save_interrupt();
    __disable_interrupt();

    bool flagState = CCADC_statusFlags.iccResultReady;
    CCADC_statusFlags.iccResultReady = false;

    __restore_interrupt( interruptState );
    
    return flagState;
}

static void CCADC_PolarityManager

(

void

)

[static]

Controls when to alter the CC-ADC input polarity.

Changes the CC-ADC input polarity every CONVERSION_COUNT conversion. Since this should be done as soon after the conversion has completed as possible this function is embedded in the ACC conversion complete interrupt rutine. It should not be called from elsewere, and is therefore static/local file scope only.

Definition at line 247 of file ccadc.c.

References CONVERSION_COUNT.

Referenced by Ccadc_Acc_ISR().

{
    static uint8_t polarityCounter = CONVERSION_COUNT;
    
    polarityCounter--;
    if(polarityCounter == 0){
        CADCSRA ^= (1<<CADPOL);
        polarityCounter = CONVERSION_COUNT;
    }
}

__interrupt void Ccadc_Rcc_ISR

(

void

)

CC-ADC Regular current threshold passed interrupt.

Definition at line 318 of file ccadc.c.

References CCADC_statusFlags, and CCADC_conversionFlag_union::regularCurrentDetected.

{
    CCADC_statusFlags.regularCurrentDetected = true;
}

void CCADC_SetMode

(

CCADC_modes_t

mode

)

Selects mode of operation for the CC-ADC.

Select between

• CCADC_DISABLE (To disable the CC-ADC, and disable and clear interrupts).
• CCADC_IAC (CC_ADC is enabled and both Instantaneous and Accumulated Conversions generate interrupts).
• CCADC_IC (CC_ADC is enabled and Instantaneous Conversions generate interrupts).
• CCADC_ACC (CC_ADC is enabled and Instantaneous Conversions generate interrupts).
• CCADC_RCC (Regular Current Condition is enabled - Note that accumulator is cleared)
  

Note:

The enabling and disabling does _not_ modify the configuration of CC-ADC. It only enable and disable the mode and interrupts.

The Bandgap voltage refence must be enabled and calibrated to used the CC-ADC

Parameters:

mode

Mode of operation.

Definition at line 127 of file ccadc.c.

References CCADC_ACC, CCADC_DISABLE, CCADC_IAC, CCADC_ICC, and CCADC_RCC.

Referenced by main().

{
    while( CADCSRA & (1<<CADUB) ){
    };
    
    switch( mode ){
        case CCADC_DISABLE:
        // Disable CC-ADC and disable interrupts (and clear pending interrupts).
        CADCSRA = CADCSRA & ~( (1<<CADEN) | (1<<CADSE) );
        CADCSRB = (0<<CADACIE) | (0<<CADRCIE) | (0<<CADICIE) | (1<<CADACIF) | (1<<CADRCIF) | (1<<CADICIF);
        break;
        
        case CCADC_IAC:
        // Enable CC-ADC with both ICC and ACC interrupts running (and clear pending interrupts).
        CADCSRA = ( CADCSRA & ~(1<<CADSE) ) | (1<<CADEN);
        CADCSRB = (1<<CADACIE) | (0<<CADRCIE) | (1<<CADICIE) | (1<<CADACIF) | (1<<CADRCIF) | (1<<CADICIF);
        break;
        
        case CCADC_ICC:
        // Enable CC-ADC with ICC interrupt running  (and clear pending interrupts).
        CADCSRA = ( CADCSRA & ~(1<<CADSE) ) | (1<<CADEN);
        CADCSRB = (0<<CADACIE) | (0<<CADRCIE) | (1<<CADICIE) | (1<<CADACIF) | (1<<CADRCIF) | (1<<CADICIF);
        break;
        
        case CCADC_ACC:
        // Enable CC-ADC with ACC interrupt running  (and clear pending interrupts).
        CADCSRA = ( CADCSRA & ~(1<<CADSE) ) | (1<<CADEN);
        CADCSRB = (1<<CADACIE) | (0<<CADRCIE) | (0<<CADICIE) | (1<<CADACIF) | (1<<CADRCIF) | (1<<CADICIF);
        break;
        
        case CCADC_RCC:
        // Enable CC-ADC with RCC and ICC interrupts running (ICC due to RCC unable to wake up device from power save).
        CADCSRA = CADCSRA | (1<<CADSE) | (1<<CADEN);
        CADCSRB = (0<<CADACIE) | (1<<CADRCIE) | (1<<CADICIE) | (1<<CADACIF) | (1<<CADRCIF) | (1<<CADICIF);  
        break;
        
        default:
        break;
    }
}

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Variable Documentation

volatile int32_t CCADC_accResult

Definition at line 56 of file ccadc.c.

Referenced by Ccadc_Acc_ISR(), and CCADC_GetAccResult().

volatile int16_t CCADC_iccResult

Definition at line 57 of file ccadc.c.

Referenced by CCADC_GetIccResult(), and Ccadc_Icc_ISR().

union CCADC_conversionFlag_union CCADC_statusFlags

Referenced by Ccadc_Acc_ISR(), Ccadc_Icc_ISR(), CCADC_isAccResultReady(), CCADC_isIccResultReady(), and Ccadc_Rcc_ISR().