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EIS/Amperometric.c

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// Amperometric.c
/*!
*****************************************************************************
@file: Amperometric.c
@author: $Author: mlambe $
@brief: Amperometric measurement.
@version: $Revision: 766 $
@date: $Date: 2018-03-21 14:09:35 +0100 (Wed, 21 Mar 2018) $
-----------------------------------------------------------------------------
Copyright (c) 2017-2019 Analog Devices, Inc. All Rights Reserved.
This software is proprietary to Analog Devices, Inc. and its licensors.
By using this software you agree to the terms of the associated
Analog Devices Software License Agreement.
*****************************************************************************/
#include "Amperometric.h"
#define AD5940ERR_STOP 10
/*
Application configuration structure. Specified by user from template.
The variables are usable in this whole application.
It includes basic configuration for sequencer generator and application related parameters
*/
AppAMPCfg_Type AppAMPCfg =
{
.bParaChanged = bFALSE,
.SeqStartAddr = 0,
.MaxSeqLen = 0,
.SeqStartAddrCal = 0,
.MaxSeqLenCal = 0,
.FifoThresh = 5, /* Number of points for FIFO */
.SysClkFreq = 16000000.0,
.WuptClkFreq = 32000.0,
.AdcClkFreq = 16000000.0,
.AmpODR = 1.0, /* Sample time in seconds. I.e. every 5 seconds make a measurement */
.NumOfData = -1,
.RcalVal = 100.0, /* RCAL = 100 Ohms */
.PwrMod = AFEPWR_LP,
.AMPInited = bFALSE,
.StopRequired = bFALSE,
/* LPTIA Configure */
.ExtRtia = bFALSE, /* Set to true if using external RTIA */
.LptiaRtiaSel = LPTIARTIA_4K, /* COnfigure RTIA */
.LpTiaRf = LPTIARF_1M, /* Configure LPF resistor */
.LpTiaRl = LPTIARLOAD_100R,
.ReDoRtiaCal = bTRUE,
.RtiaCalValue = 0,
.ExtRtiaVal = 0,
/*LPDAC Configure */
.Vzero = 1100, /* Sets voltage on SE0 and LPTIA */
.SensorBias = 500, /* Sets voltage between RE0 and SE0 */
/* ADC Configure*/
.ADCPgaGain = ADCPGA_1P5,
.ADCSinc3Osr = ADCSINC3OSR_4,
.ADCSinc2Osr = ADCSINC2OSR_22,
.DataFifoSrc = FIFOSRC_SINC2NOTCH,
.ADCRefVolt = 1.8162, /* Measure voltage on ADCRefVolt pin and enter here*/
};
/**
This function is provided for upper controllers that want to change
application parameters specially for user defined parameters.
*/
AD5940Err AppAMPGetCfg(void *pCfg)
{
if(pCfg){
*(AppAMPCfg_Type**)pCfg = &AppAMPCfg;
return AD5940ERR_OK;
}
return AD5940ERR_PARA;
}
AD5940Err AppAMPCtrl(int32_t AmpCtrl, void *pPara)
{
switch (AmpCtrl)
{
case AMPCTRL_START:
{
WUPTCfg_Type wupt_cfg;
AD5940_ReadReg(REG_AFE_ADCDAT); /* Any SPI Operation can wakeup AFE */
if(AppAMPCfg.AMPInited == bFALSE)
return AD5940ERR_APPERROR;
/* Start it */
wupt_cfg.WuptEn = bTRUE;
wupt_cfg.WuptEndSeq = WUPTENDSEQ_A;
wupt_cfg.WuptOrder[0] = SEQID_0;
wupt_cfg.SeqxSleepTime[SEQID_0] = 4-1;
wupt_cfg.SeqxWakeupTime[SEQID_0] = (uint32_t)(AppAMPCfg.WuptClkFreq*AppAMPCfg.AmpODR)-4-1;
AD5940_WUPTCfg(&wupt_cfg);
AppAMPCfg.FifoDataCount = 0; /* restart */
break;
}
case AMPCTRL_STOPNOW:
{
AD5940_ReadReg(REG_AFE_ADCDAT); /* Any SPI Operation can wakeup AFE */
/* Start Wupt right now */
AD5940_WUPTCtrl(bFALSE);
/* There is chance this operation will fail because sequencer could put AFE back
to hibernate mode just after waking up. Use STOPSYNC is better. */
AD5940_WUPTCtrl(bFALSE);
break;
}
case AMPCTRL_STOPSYNC:
{
AppAMPCfg.StopRequired = bTRUE;
break;
}
case AMPCTRL_SHUTDOWN:
{
AppAMPCtrl(AMPCTRL_STOPNOW, 0); /* Stop the measurement if it's running. */
/* Turn off LPloop related blocks which are not controlled automatically by sleep operation */
AFERefCfg_Type aferef_cfg;
LPLoopCfg_Type lp_loop;
memset(&aferef_cfg, 0, sizeof(aferef_cfg));
AD5940_REFCfgS(&aferef_cfg);
memset(&lp_loop, 0, sizeof(lp_loop));
AD5940_LPLoopCfgS(&lp_loop);
AD5940_EnterSleepS(); /* Enter Hibernate */
}
break;
default:
break;
}
return AD5940ERR_OK;
}
/* Generate init sequence */
static AD5940Err AppAMPSeqCfgGen(void)
{
AD5940Err error = AD5940ERR_OK;
uint32_t const *pSeqCmd;
uint32_t SeqLen;
AFERefCfg_Type aferef_cfg;
LPLoopCfg_Type lp_loop;
DSPCfg_Type dsp_cfg;
SWMatrixCfg_Type sw_cfg;
/* Start sequence generator here */
AD5940_SEQGenCtrl(bTRUE);
//AD5940_AFECtrlS(AFECTRL_ALL, bFALSE); /* Init all to disable state */
aferef_cfg.HpBandgapEn = bTRUE;
aferef_cfg.Hp1V1BuffEn = bTRUE;
aferef_cfg.Hp1V8BuffEn = bTRUE;
aferef_cfg.Disc1V1Cap = bFALSE;
aferef_cfg.Disc1V8Cap = bFALSE;
aferef_cfg.Hp1V8ThemBuff = bFALSE;
aferef_cfg.Hp1V8Ilimit = bFALSE;
aferef_cfg.Lp1V1BuffEn = bTRUE;
aferef_cfg.Lp1V8BuffEn = bTRUE;
/* LP reference control - turn off them to save power*/
aferef_cfg.LpBandgapEn = bTRUE;
aferef_cfg.LpRefBufEn = bTRUE;
aferef_cfg.LpRefBoostEn = bFALSE;
AD5940_REFCfgS(&aferef_cfg);
lp_loop.LpDacCfg.LpdacSel = LPDAC0;
lp_loop.LpDacCfg.LpDacSrc = LPDACSRC_MMR;
lp_loop.LpDacCfg.LpDacSW = LPDACSW_VBIAS2LPPA|LPDACSW_VBIAS2PIN|LPDACSW_VZERO2LPTIA|LPDACSW_VZERO2PIN;
lp_loop.LpDacCfg.LpDacVzeroMux = LPDACVZERO_6BIT;
lp_loop.LpDacCfg.LpDacVbiasMux = LPDACVBIAS_12BIT;
lp_loop.LpDacCfg.LpDacRef = LPDACREF_2P5;
lp_loop.LpDacCfg.DataRst = bFALSE;
lp_loop.LpDacCfg.PowerEn = bTRUE;
lp_loop.LpDacCfg.DacData6Bit = (uint32_t)((AppAMPCfg.Vzero-200)/DAC6BITVOLT_1LSB);
lp_loop.LpDacCfg.DacData12Bit =(int32_t)((AppAMPCfg.SensorBias)/DAC12BITVOLT_1LSB) + lp_loop.LpDacCfg.DacData6Bit*64;
if(lp_loop.LpDacCfg.DacData12Bit>lp_loop.LpDacCfg.DacData6Bit*64)
lp_loop.LpDacCfg.DacData12Bit--;
lp_loop.LpAmpCfg.LpAmpSel = LPAMP0;
lp_loop.LpAmpCfg.LpAmpPwrMod = LPAMPPWR_NORM;
lp_loop.LpAmpCfg.LpPaPwrEn = bTRUE;
lp_loop.LpAmpCfg.LpTiaPwrEn = bTRUE;
lp_loop.LpAmpCfg.LpTiaRf = AppAMPCfg.LpTiaRf;
lp_loop.LpAmpCfg.LpTiaRload = AppAMPCfg.LpTiaRl;
if(AppAMPCfg.ExtRtia == bTRUE)
{
lp_loop.LpAmpCfg.LpTiaRtia = LPTIARTIA_OPEN;
lp_loop.LpAmpCfg.LpTiaSW = LPTIASW(9)|LPTIASW(2)|LPTIASW(4)|LPTIASW(5)|LPTIASW(12)|LPTIASW(13);
}else
{
lp_loop.LpAmpCfg.LpTiaRtia = AppAMPCfg.LptiaRtiaSel;
lp_loop.LpAmpCfg.LpTiaSW = LPTIASW(5)|LPTIASW(2)|LPTIASW(4)|LPTIASW(12)|LPTIASW(13);
}
AD5940_LPLoopCfgS(&lp_loop);
dsp_cfg.ADCBaseCfg.ADCMuxN = ADCMUXN_VZERO0;
dsp_cfg.ADCBaseCfg.ADCMuxP = ADCMUXP_AIN4;
dsp_cfg.ADCBaseCfg.ADCPga = AppAMPCfg.ADCPgaGain;
memset(&dsp_cfg.ADCDigCompCfg, 0, sizeof(dsp_cfg.ADCDigCompCfg));
memset(&dsp_cfg.DftCfg, 0, sizeof(dsp_cfg.DftCfg));
dsp_cfg.ADCFilterCfg.ADCAvgNum = ADCAVGNUM_16; /* Don't care because it's disabled */
dsp_cfg.ADCFilterCfg.ADCRate = ADCRATE_800KHZ; /* Tell filter block clock rate of ADC*/
dsp_cfg.ADCFilterCfg.ADCSinc2Osr = AppAMPCfg.ADCSinc2Osr;
dsp_cfg.ADCFilterCfg.ADCSinc3Osr = AppAMPCfg.ADCSinc3Osr;
dsp_cfg.ADCFilterCfg.BpSinc3 = bFALSE;
dsp_cfg.ADCFilterCfg.BpNotch = bFALSE;
dsp_cfg.ADCFilterCfg.Sinc2NotchEnable = bTRUE;
memset(&dsp_cfg.StatCfg, 0, sizeof(dsp_cfg.StatCfg)); /* Don't care about Statistic */
AD5940_DSPCfgS(&dsp_cfg);
sw_cfg.Dswitch = 0;
sw_cfg.Pswitch = 0;
sw_cfg.Nswitch = 0;
sw_cfg.Tswitch = 0;
AD5940_SWMatrixCfgS(&sw_cfg);
/* Enable all of them. They are automatically turned off during hibernate mode to save power */
AD5940_AFECtrlS(AFECTRL_HPREFPWR|AFECTRL_SINC2NOTCH, bTRUE);
AD5940_AFECtrlS(AFECTRL_SINC2NOTCH, bFALSE);
AD5940_SEQGpioCtrlS(0/*AGPIO_Pin6|AGPIO_Pin5|AGPIO_Pin1*/); //GP6->endSeq, GP5 -> AD8233=OFF, GP1->RLD=OFF .
/* Sequence end. */
AD5940_SEQGenInsert(SEQ_STOP()); /* Add one extra command to disable sequencer for initialization sequence because we only want it to run one time. */
/* Stop here */
error = AD5940_SEQGenFetchSeq(&pSeqCmd, &SeqLen);
AD5940_SEQGenCtrl(bFALSE); /* Stop sequencer generator */
if(error == AD5940ERR_OK)
{
AppAMPCfg.InitSeqInfo.SeqId = SEQID_1;
AppAMPCfg.InitSeqInfo.SeqRamAddr = AppAMPCfg.SeqStartAddr;
AppAMPCfg.InitSeqInfo.pSeqCmd = pSeqCmd;
AppAMPCfg.InitSeqInfo.SeqLen = SeqLen;
/* Write command to SRAM */
AD5940_SEQCmdWrite(AppAMPCfg.InitSeqInfo.SeqRamAddr, pSeqCmd, SeqLen);
}
else
return error; /* Error */
return AD5940ERR_OK;
}
static AD5940Err AppAMPSeqMeasureGen(void)
{
AD5940Err error = AD5940ERR_OK;
uint32_t const *pSeqCmd;
uint32_t SeqLen;
uint32_t WaitClks;
ClksCalInfo_Type clks_cal;
clks_cal.DataType = DATATYPE_SINC2;
clks_cal.DataCount = 1;
clks_cal.ADCSinc2Osr = AppAMPCfg.ADCSinc2Osr;
clks_cal.ADCSinc3Osr = AppAMPCfg.ADCSinc3Osr;
clks_cal.ADCAvgNum = 0;
clks_cal.RatioSys2AdcClk = AppAMPCfg.SysClkFreq/AppAMPCfg.AdcClkFreq;
AD5940_ClksCalculate(&clks_cal, &WaitClks);
WaitClks += 15;
AD5940_SEQGenCtrl(bTRUE);
AD5940_SEQGpioCtrlS(AGPIO_Pin2);
AD5940_AFECtrlS(AFECTRL_ADCPWR|AFECTRL_SINC2NOTCH, bTRUE);
AD5940_SEQGenInsert(SEQ_WAIT(16*250)); /* wait 250us */
AD5940_AFECtrlS(AFECTRL_ADCCNV, bTRUE); /* Start ADC convert*/
AD5940_SEQGenInsert(SEQ_WAIT(WaitClks)); /* wait for first data ready */
AD5940_AFECtrlS(AFECTRL_ADCPWR|AFECTRL_ADCCNV|AFECTRL_SINC2NOTCH, bFALSE); /* Stop ADC */
AD5940_SEQGpioCtrlS(0);
AD5940_EnterSleepS();/* Goto hibernate */
/* Sequence end. */
error = AD5940_SEQGenFetchSeq(&pSeqCmd, &SeqLen);
AD5940_SEQGenCtrl(bFALSE); /* Stop sequencer generator */
if(error == AD5940ERR_OK)
{
AppAMPCfg.MeasureSeqInfo.SeqId = SEQID_0;
AppAMPCfg.MeasureSeqInfo.SeqRamAddr = AppAMPCfg.InitSeqInfo.SeqRamAddr + AppAMPCfg.InitSeqInfo.SeqLen ;
AppAMPCfg.MeasureSeqInfo.pSeqCmd = pSeqCmd;
AppAMPCfg.MeasureSeqInfo.SeqLen = SeqLen;
/* Write command to SRAM */
AD5940_SEQCmdWrite(AppAMPCfg.MeasureSeqInfo.SeqRamAddr, pSeqCmd, SeqLen);
}
else
return error; /* Error */
return AD5940ERR_OK;
}
static AD5940Err AppAMPRtiaCal(void)
{
fImpPol_Type RtiaCalValue; /* Calibration result */
LPRTIACal_Type lprtia_cal;
AD5940_StructInit(&lprtia_cal, sizeof(lprtia_cal));
lprtia_cal.bPolarResult = bTRUE; /* Magnitude + Phase */
lprtia_cal.AdcClkFreq = AppAMPCfg.AdcClkFreq;
lprtia_cal.SysClkFreq = AppAMPCfg.SysClkFreq;
lprtia_cal.ADCSinc3Osr = ADCSINC3OSR_4;
lprtia_cal.ADCSinc2Osr = ADCSINC2OSR_22; /* Use SINC2 data as DFT data source */
lprtia_cal.DftCfg.DftNum = DFTNUM_2048; /* Maximum DFT number */
lprtia_cal.DftCfg.DftSrc = DFTSRC_SINC2NOTCH; /* For frequency under 12Hz, need to optimize DFT source. Use SINC3 data as DFT source */
lprtia_cal.DftCfg.HanWinEn = bTRUE;
lprtia_cal.fFreq = AppAMPCfg.AdcClkFreq/4/22/2048*3; /* Sample 3 period of signal, 13.317Hz here. Do not use DC method, because it needs ADC/PGA calibrated firstly(but it's faster) */
lprtia_cal.fRcal = AppAMPCfg.RcalVal;
lprtia_cal.LpTiaRtia = AppAMPCfg.LptiaRtiaSel;
lprtia_cal.LpAmpPwrMod = LPAMPPWR_NORM;
lprtia_cal.bWithCtia = bFALSE;
AD5940_LPRtiaCal(&lprtia_cal, &RtiaCalValue);
AppAMPCfg.RtiaCalValue = RtiaCalValue;
return AD5940ERR_OK;
}
/* This function provide application initialize. */
AD5940Err AppAMPInit(uint32_t *pBuffer, uint32_t BufferSize)
{
AD5940Err error = AD5940ERR_OK;
SEQCfg_Type seq_cfg;
FIFOCfg_Type fifo_cfg;
if(AD5940_WakeUp(10) > 10) /* Wakeup AFE by read register, read 10 times at most */
return AD5940ERR_WAKEUP; /* Wakeup Failed */
/* Configure sequencer and stop it */
seq_cfg.SeqMemSize = SEQMEMSIZE_2KB; /* 2kB SRAM is used for sequencer, others for data FIFO */
seq_cfg.SeqBreakEn = bFALSE;
seq_cfg.SeqIgnoreEn = bFALSE;
seq_cfg.SeqCntCRCClr = bTRUE;
seq_cfg.SeqEnable = bFALSE;
seq_cfg.SeqWrTimer = 0;
AD5940_SEQCfg(&seq_cfg);
/* Do RTIA calibration */
if(((AppAMPCfg.ReDoRtiaCal == bTRUE) || \
AppAMPCfg.AMPInited == bFALSE) && AppAMPCfg.ExtRtia == bFALSE) /* Do calibration on the first initializaion */
{
AppAMPRtiaCal();
AppAMPCfg.ReDoRtiaCal = bFALSE;
}else
AppAMPCfg.RtiaCalValue.Magnitude = AppAMPCfg.ExtRtiaVal;
/* Reconfigure FIFO */
AD5940_FIFOCtrlS(DFTSRC_SINC3, bFALSE); /* Disable FIFO firstly */
fifo_cfg.FIFOEn = bTRUE;
fifo_cfg.FIFOMode = FIFOMODE_FIFO;
fifo_cfg.FIFOSize = FIFOSIZE_4KB; /* 4kB for FIFO, The reset 2kB for sequencer */
fifo_cfg.FIFOSrc = AppAMPCfg.DataFifoSrc;
fifo_cfg.FIFOThresh = AppAMPCfg.FifoThresh;
AD5940_FIFOCfg(&fifo_cfg);
AD5940_INTCClrFlag(AFEINTSRC_ALLINT);
/* Start sequence generator */
/* Initialize sequencer generator */
if((AppAMPCfg.AMPInited == bFALSE)||\
(AppAMPCfg.bParaChanged == bTRUE))
{
if(pBuffer == 0) return AD5940ERR_PARA;
if(BufferSize == 0) return AD5940ERR_PARA;
AD5940_SEQGenInit(pBuffer, BufferSize);
/* Generate initialize sequence */
error = AppAMPSeqCfgGen(); /* Application initialization sequence using either MCU or sequencer */
if(error != AD5940ERR_OK) return error;
/* Generate measurement sequence */
error = AppAMPSeqMeasureGen();
if(error != AD5940ERR_OK) return error;
AppAMPCfg.bParaChanged = bFALSE; /* Clear this flag as we already implemented the new configuration */
}
/* Initialization sequencer */
AppAMPCfg.InitSeqInfo.WriteSRAM = bFALSE;
AD5940_SEQInfoCfg(&AppAMPCfg.InitSeqInfo);
seq_cfg.SeqEnable = bTRUE;
AD5940_SEQCfg(&seq_cfg); /* Enable sequencer */
AD5940_SEQMmrTrig(AppAMPCfg.InitSeqInfo.SeqId);
while(AD5940_INTCTestFlag(AFEINTC_1, AFEINTSRC_ENDSEQ) == bFALSE);
/* Measurement sequence */
AppAMPCfg.MeasureSeqInfo.WriteSRAM = bFALSE;
AD5940_SEQInfoCfg(&AppAMPCfg.MeasureSeqInfo);
// seq_cfg.SeqEnable = bTRUE;
// AD5940_SEQCfg(&seq_cfg); /* Enable sequencer, and wait for trigger */
AD5940_SEQCtrlS(bTRUE); /* Enable sequencer, and wait for trigger. It's disabled in initialization sequence */
AD5940_ClrMCUIntFlag(); /* Clear interrupt flag generated before */
AD5940_AFEPwrBW(AppAMPCfg.PwrMod, AFEBW_250KHZ);
AppAMPCfg.AMPInited = bTRUE; /* AMP application has been initialized. */
return AD5940ERR_OK;
}
/* Modify registers when AFE wakeup */
static AD5940Err AppAMPRegModify(int32_t * const pData, uint32_t *pDataCount)
{
if(AppAMPCfg.NumOfData > 0)
{
AppAMPCfg.FifoDataCount += *pDataCount/4;
if(AppAMPCfg.FifoDataCount >= AppAMPCfg.NumOfData)
{
AD5940_WUPTCtrl(bFALSE);
return AD5940ERR_STOP; // Return STOP code
}
}
if(AppAMPCfg.StopRequired == bTRUE)
{
AD5940_WUPTCtrl(bFALSE);
return AD5940ERR_OK;
}
return AD5940ERR_OK;
}
/* Depending on the data type, do appropriate data pre-process before return back to controller */
static AD5940Err AppAMPDataProcess(int32_t * const pData, uint32_t *pDataCount)
{
uint32_t i, datacount;
datacount = *pDataCount;
float *pOut = (float *)pData;
for(i=0;i<datacount;i++)
{
pData[i] &= 0xffff;
pOut[i] = AppAMPCalcCurrent(pData[i]);
}
return AD5940ERR_OK;
}
/**
*/
AD5940Err AppAMPISR(void *pBuff, uint32_t *pCount)
{
uint32_t FifoCnt;
if(AD5940_WakeUp(10) > 10) /* Wakeup AFE by read register, read 10 times at most */
return AD5940ERR_WAKEUP; /* Wakeup Failed */
AD5940_SleepKeyCtrlS(SLPKEY_LOCK);
*pCount = 0;
if(AD5940_INTCTestFlag(AFEINTC_0, AFEINTSRC_DATAFIFOTHRESH) == bTRUE)
{
FifoCnt = AD5940_FIFOGetCnt();
AD5940_FIFORd((uint32_t *)pBuff, FifoCnt);
AD5940_INTCClrFlag(AFEINTSRC_DATAFIFOTHRESH);
AD5940Err status = AppAMPRegModify(pBuff, &FifoCnt); /* If there is need to do AFE re-configure, do it here when AFE is in active state */
AD5940_SleepKeyCtrlS(SLPKEY_UNLOCK);
//AD5940_EnterSleepS(); /* Manually put AFE back to hibernate mode. This operation only takes effect when register value is ACTIVE previously */
/* Process data */
AppAMPDataProcess((int32_t*)pBuff,&FifoCnt);
*pCount = FifoCnt;
if (status == AD5940ERR_STOP) return AD5940ERR_STOP;
return 0;
}
return 0;
}
/* Calculate voltage */
float AppAMPCalcVoltage(uint32_t ADCcode)
{
float kFactor = 1.835/1.82;
float fVolt = 0.0;
int32_t tmp = 0;
tmp = ADCcode - 32768;
switch(AppAMPCfg.ADCPgaGain)
{
case ADCPGA_1:
fVolt = ((float)(tmp)/32768)*(AppAMPCfg.ADCRefVolt/1)*kFactor;
break;
case ADCPGA_1P5:
fVolt = ((float)(tmp)/32768)*(AppAMPCfg.ADCRefVolt/1.5f)*kFactor;
break;
case ADCPGA_2:
fVolt = ((float)(tmp)/32768)*(AppAMPCfg.ADCRefVolt/2)*kFactor;
break;
case ADCPGA_4:
fVolt = ((float)(tmp)/32768)*(AppAMPCfg.ADCRefVolt/4)*kFactor;
break;
case ADCPGA_9:
fVolt = ((float)(tmp)/32768)*(AppAMPCfg.ADCRefVolt/9)*kFactor;
break;
}
return fVolt;
}
/* Calculate current in uA */
float AppAMPCalcCurrent(uint32_t ADCcode)
{
float fCurrent, fVoltage = 0.0;
fVoltage = AppAMPCalcVoltage(ADCcode);
fCurrent = fVoltage/AppAMPCfg.RtiaCalValue.Magnitude;
return -fCurrent*1000000;
}
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