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/* ----------------------------------------------------------------------------
* ATMEL Microcontroller Software Support
* ----------------------------------------------------------------------------
* 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:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the disclaimer below.
*
* Atmel's name may not be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* 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.
* ----------------------------------------------------------------------------
*/
//------------------------------------------------------------------------------
// Headers
//------------------------------------------------------------------------------
#include <board.h>
#include <adc/adc12.h>
#include <utility/trace.h>
#include <utility/assert.h>
//------------------------------------------------------------------------------
// Global Functions
//------------------------------------------------------------------------------
//-----------------------------------------------------------------------------
/// Initialize the ADC controller
/// \param pAdc Pointer to an AT91S_ADC instance.
/// \param trgEn trigger mode, software or Hardware
/// \param trgSel hardware trigger selection
/// \param sleepMode sleep mode selection
/// \param resolution resolution selection 8 bits or 10 bits
/// \param mckClock value of MCK in Hz
/// \param adcClock value of the ADC clock in Hz
/// \param startupTime value of the start up time (in us) (see datasheet)
/// \param sampleAndHoldTime (in ns)
//-----------------------------------------------------------------------------
void ADC12_Initialize (AT91S_ADC12B *pAdc,
unsigned char idAdc,
unsigned char trgEn,
unsigned char trgSel,
unsigned char sleepMode,
unsigned char resolution,
unsigned int mckClock,
unsigned int adcClock,
unsigned int startupTime,
unsigned int sampleAndHoldTime)
{
unsigned int prescal;
unsigned int startup;
unsigned int shtim;
ASSERT(startupTime<=ADC_STARTUP_TIME_MAX, "ADC Bad startupTime\n\r");
ASSERT(sampleAndHoldTime>=ADC_TRACK_HOLD_TIME_MIN, "ADC Bad sampleAndHoldTime\n\r");
// Example:
// 5 MHz operation, 20µs startup time, 600ns track and hold time
// PRESCAL: Prescaler Rate Selection ADCClock = MCK / ( (PRESCAL+1) * 2 )
// PRESCAL = [MCK / (ADCClock * 2)] -1 = [48/(5*2)]-1 = 3,8
// PRESCAL = 4 -> 48/((4+1)*2) = 48/10 = 4.8MHz
// 48/((3+1)*2) = 48/8 = 6MHz
// Startup Time = (STARTUP+1) * 8 / ADCClock
// STARTUP = [(Startup Time * ADCClock)/8]-1 = [(20 10e-6 * 5000000)/8]-1 = 11,5
// STARTUP = 11 -> (11+1)*8/48000000 = 96/4800000 = 20us
//
// Sample & Hold Time = (SHTIM) / ADCClock
// SHTIM = (HoldTime * ADCClock)-1 = (600 10e-9 * 5000000) = 3
// SHTIM = 3 -> (3)/4800000 = 1/1600000 = 625ns
prescal = (mckClock / (2*adcClock)) - 1;
startup = ((adcClock/1000000) * startupTime / 8) - 1;
shtim = (((adcClock/1000000) * sampleAndHoldTime)/1000);
ASSERT( (prescal<0x3F), "ADC12 Bad PRESCAL\n\r");
ASSERT(startup<0x7F, "ADC12 Bad STARTUP\n\r");
ASSERT(shtim<0xF, "ADC12 Bad SampleAndHoldTime\n\r");
TRACE_DEBUG("adcClock:%d MasterClock:%d\n\r", (mckClock/((prescal+1)*2)), mckClock);
TRACE_DEBUG("prescal:0x%X startup:0x%X shtim:0x%X\n\r", prescal, startup, shtim);
if( adcClock != (mckClock/((prescal+1)*2)) ) {
TRACE_WARNING("User and calculated adcClocks are different : user=%d calc=%d\n\r",
adcClock, (mckClock/((prescal+1)*2)));
}
// Enable peripheral clock
AT91C_BASE_PMC->PMC_PCER = 1 << idAdc;
// Reset the controller
ADC12_SoftReset(pAdc);
// Write to the MR register
ADC12_CfgModeReg( pAdc,
( trgEn & AT91C_ADC12B_MR_TRGEN)
| ( trgSel & AT91C_ADC12B_MR_TRGSEL)
| ( resolution & AT91C_ADC12B_MR_LOWRES)
| ( sleepMode & AT91C_ADC12B_MR_SLEEP)
| ( (prescal<<8) & AT91C_ADC12B_MR_PRESCAL)
| ( (startup<<16) & AT91C_ADC12B_MR_STARTUP)
| ( (shtim<<24) & AT91C_ADC12B_MR_SHTIM) );
}
//-----------------------------------------------------------------------------
/// Return the Channel Converted Data
/// \param pAdc Pointer to an AT91S_ADC instance.
/// \param channel channel to get converted value
/// \return Channel converted data of the specified channel
//-----------------------------------------------------------------------------
unsigned int ADC12_GetConvertedData(AT91S_ADC12B *pAdc, unsigned int channel)
{
unsigned int data=0;
ASSERT(channel < 8, "ADC channel %u not exist", channel);
switch(channel) {
case 0: data = pAdc->ADC12B_CDR[0]; break;
case 1: data = pAdc->ADC12B_CDR[1]; break;
case 2: data = pAdc->ADC12B_CDR[2]; break;
case 3: data = pAdc->ADC12B_CDR[3]; break;
case 4: data = pAdc->ADC12B_CDR[4]; break;
case 5: data = pAdc->ADC12B_CDR[5]; break;
case 6: data = pAdc->ADC12B_CDR[6]; break;
case 7: data = pAdc->ADC12B_CDR[7]; break;
default: printf("\n\r Channel is not available!\n\r");
}
return data;
}
//-----------------------------------------------------------------------------
/// Test if ADC Interrupt is Masked
/// \param pAdc Pointer to an AT91S_ADC instance.
/// \param flag flag to be tested
/// \return 1 if interrupt is masked, otherwise 0
//-----------------------------------------------------------------------------
unsigned int ADC12_IsInterruptMasked(AT91S_ADC12B *pAdc, unsigned int flag)
{
return (ADC12_GetInterruptMaskStatus(pAdc) & flag);
}
//-----------------------------------------------------------------------------
/// Test if ADC Status is Set
/// \param pAdc Pointer to an AT91S_ADC instance.
/// \param flag flag to be tested
/// \return 1 if the staus is set; 0 otherwise
//-----------------------------------------------------------------------------
unsigned int ADC12_IsStatusSet(AT91S_ADC12B *pAdc, unsigned int flag)
{
return (ADC12_GetStatus(pAdc) & flag);
}
//-----------------------------------------------------------------------------
/// Test if ADC channel interrupt Status is Set
/// \param adc_sr Value of SR register
/// \param channel Channel to be tested
/// \return 1 if interrupt status is set, otherwise 0
//-----------------------------------------------------------------------------
unsigned char ADC12_IsChannelInterruptStatusSet(unsigned int adc_sr,
unsigned int channel)
{
unsigned char status;
if((adc_sr & (1<<channel)) == (1<<channel)) {
status = 1;
}
else {
status = 0;
}
return status;
}
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