I change BiaODR value, but the sampling frequency w does not change as this.So I would like to ask how to change the sampling frequency in the 4-wire BIA measurement, because I need a sampling frequency of 1000hz.thanks.
AD5940
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The AD5940 and AD5941 are high precision, low power analog front ends (AFEs) designed for portable applications that require high precision, electrochemical...
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I change BiaODR value, but the sampling frequency w does not change as this.So I would like to ask how to change the sampling frequency in the 4-wire BIA measurement, because I need a sampling frequency of 1000hz.thanks.
Hi,
With the default AFE configuration, max allowed ODR is 10Hz.
For ODR more than this, ADC filter parameters must be changed.
If you are running the code through IDE (Keil or IAR), you may add the below code ) inside AppBIASeqMeasureGen () and add to watch “AppBIACfg.MaxODR”, to know the maximum sampling rate allowed for the set configuration.
AppBIACfg.MeasSeqCycleCount = AD5940_SEQCycleTime();
AppBIACfg.MaxODR = 1/((( AppBIACfg.MeasSeqCycleCount + 10) / 16.0)* 1E-6) ; //If Sysclk is16MHz
if(AppBIACfg.BiaODR > AppBiaCfg.MaxODR)
{
/* We have requested a sampling rate that cannot be achieved with the time it takes to acquire a sample.*/
AppBIACfg.BiaODR = AppBIACfg.MaxODR;
}
With the default AFE configuration, max allowed ODR is 10Hz.
thanks,Actually it already exists.But the sampling frequency does not change.so I want to know what BiaODR is for.
Thanks,
So where can I change the ADC filter configuration to increase the MaxODR?
and I have increased BiaODR,,but the output data rate don't increase at all.
Hello,
Has this issue been resolved? I have a similar problem as well. Thank you!.
No, this question still haunts me.and What is your question?
Hi,
Changing the below parameters in BodyImpedance.c file changes maxODR:
AppBIACfg.DftNum
AppBIACfg.ADCSinc2Osr
AppBIACfg.ADCSinc3Osr
Hello Akila,
Thank you for the prompt response! I was wondering what exactly should be changed within those lines of code. I was looking at the BIOZ-2Wire example and I don't see any numerical values for me to change given the codes you just provided.
This is what I am currently seeing:
OR
Thank you!
Very similar to your question about the sampling rate for the AD5940 Board
Hi,
Because I calculated the value of maxodr is 47 , So no matter how I change the Biaodr value, there is no effect on the output frequency.
so can I delete the configuration of maxodr in here? only use the Biaodr。
Hi,
If MaxODR is 47 samples/s and if you are setting BiaODR =50, it is not going to provide 50Hz Output rate. Hence keeping the MaxODR block ensures clarity.
Hi,
Then how can I increase the output frequency to more than 50hz?
Do I have to raise the MAXODR, and how do I increase the value of this?
Change
pBIACfg->DftNum = DFTNUM_8192;
pBIACfg->ADCSinc3Osr = ADCSINC3OSR_2;
in AD5940Main.c
and
.ADCSinc2Osr = ADCSINC2OSR_22,
in BodyImpedance.c
Change
pBIACfg->DftNum = DFTNUM_8192;
pBIACfg->ADCSinc3Osr = ADCSINC3OSR_2;
in AD5940Main.c
and
.ADCSinc2Osr = ADCSINC2OSR_22,
in BodyImpedance.c
But when I change these values,the accuracy of the data decreases
Hello Akila,
Are these parameter changes also applicable in the BIOZ-2Wire example as well?.
I can only locate AppBIOZCfg.DftNum, AppBIOZCfg.ADCSinc20sr, and AppBIOZCfg.ADCSinc30sr in the BIOZ-2Wire.c within the AppBIOZSeqCfgGen() section. Would directly replacing the codes with the changes you suggested work?
Thank you
It would be good to know the FULL code modfications to get to 1000Hz sampling rate, which would be similar to a benchtop Zurich instrument, which we would like to compare to. There seems to be lots of partial code answers - please provide the full code and maximum sampling rate and ideally the loss in accuracy from the 4Hz example in the documentation and the desirable 1000Hz sampling rate.
Hi,
Change the red parts in the BIOZ-2Wire.c code below to change MaxODR value:
/******************************************************************************
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 "BIOZ-2Wire.h"
/**
* @note This example is modified from BIOZ example. This one is for 2-wire impedance measuremnt.
* The default pins used are CE0 and AIN2. The differnce with BIOZ is that the body voltage
* Measurment is replaced with excitation voltage measurment and it's only measured once.
*/
/*
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
*/
AppBIOZCfg_Type AppBIOZCfg =
{
.bParaChanged = bFALSE,
.SeqStartAddr = 0,
.MaxSeqLen = 0,
.SeqStartAddrCal = 0,
.MaxSeqLenCal = 0,
.ReDoRtiaCal = bFALSE,
.SysClkFreq = 16000000.0,
.WuptClkFreq = 32000.0,
.AdcClkFreq = 16000000.0,
.BIOZODR = 20.0, /* 20.0 Hz*/
.NumOfData = -1,
.RcalVal = 10000.0, /* 10kOhm */
.PwrMod = AFEPWR_LP,
.HstiaRtiaSel = HSTIARTIA_10K,
.CtiaSel = 16,
.ExcitBufGain = EXCITBUFGAIN_2,
.HsDacGain = HSDACGAIN_1,
.HsDacUpdateRate = 7,
.DacVoltPP = 600.0,
.SinFreq = 50000.0, /* 5000Hz */
.ADCPgaGain = ADCPGA_1P5,
.ADCSinc3Osr = ADCSINC3OSR_2,
.ADCSinc2Osr = ADCSINC2OSR_22,
.DftNum = DFTNUM_8192,
.DftSrc = DFTSRC_SINC3,
.HanWinEn = bTRUE,
.SweepCfg.SweepEn = bFALSE,
.SweepCfg.SweepStart = 10000,
.SweepCfg.SweepStop = 150000.0,
.SweepCfg.SweepPoints = 100,
.SweepCfg.SweepLog = bTRUE,
.SweepCfg.SweepIndex = 0,
.FifoThresh = 4, /* Must be 4 when SweepEn = bTRUE*/
.BIOZInited = bFALSE,
.StopRequired = bFALSE,
};
/**
This function is provided for upper controllers that want to change
application parameters specially for user defined parameters.
*/
AD5940Err AppBIOZGetCfg(void *pCfg)
{
if(pCfg){
*(AppBIOZCfg_Type**)pCfg = &AppBIOZCfg;
return AD5940ERR_OK;
}
return AD5940ERR_PARA;
}
AD5940Err AppBIOZCtrl(int32_t BcmCtrl, void *pPara)
{
switch (BcmCtrl)
{
case BIOZCTRL_START:
{
WUPTCfg_Type wupt_cfg;
if(AD5940_WakeUp(10) > 10) /* Wakeup AFE by read register, read 10 times at most */
return AD5940ERR_WAKEUP; /* Wakeup Failed */
if(AppBIOZCfg.BIOZInited == bFALSE)
return AD5940ERR_APPERROR;
/* Start the wakeup timer */
wupt_cfg.WuptEn = bTRUE;
wupt_cfg.WuptEndSeq = WUPTENDSEQ_A;
wupt_cfg.WuptOrder[0] = SEQID_0;
wupt_cfg.SeqxSleepTime[SEQID_0] = (uint32_t)(AppBIOZCfg.WuptClkFreq/AppBIOZCfg.BIOZODR)-2-1;
wupt_cfg.SeqxWakeupTime[SEQID_0] = 1; /* The minimum value is 1. Do not set it to zero. Set it to 1 will spend 2 32kHz clock. */
AD5940_WUPTCfg(&wupt_cfg);
AppBIOZCfg.FifoDataCount = 0; /* restart */
#ifdef ADI_DEBUG
ADI_Print("BIOZ Start...\n");
#endif
break;
}
case BIOZCTRL_STOPNOW:
{
if(AD5940_WakeUp(10) > 10) /* Wakeup AFE by read register, read 10 times at most */
return AD5940ERR_WAKEUP; /* Wakeup Failed */
/* Stop Wupt right now */
AD5940_WUPTCtrl(bFALSE);
AD5940_WUPTCtrl(bFALSE);
#ifdef ADI_DEBUG
ADI_Print("BIOZ Stop Now...\n");
#endif
break;
}
case BIOZCTRL_STOPSYNC:
{
#ifdef ADI_DEBUG
ADI_Print("BIOZ Stop SYNC...\n");
#endif
AppBIOZCfg.StopRequired = bTRUE;
break;
}
case BIOZCTRL_GETFREQ:
if(pPara)
{
if(AppBIOZCfg.SweepCfg.SweepEn == bTRUE)
*(float*)pPara = AppBIOZCfg.FreqofData;
else
*(float*)pPara = AppBIOZCfg.SinFreq;
}
break;
case BIOZCTRL_SHUTDOWN:
{
AppBIOZCtrl(BIOZCTRL_STOPNOW, 0); /* Stop the measurment 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 */
#ifdef ADI_DEBUG
ADI_Print("BIOZ Shut down...\n");
#endif
}
break;
default:
break;
}
return AD5940ERR_OK;
}
/* Generate init sequence */
static AD5940Err AppBIOZSeqCfgGen(void)
{
AD5940Err error = AD5940ERR_OK;
uint32_t const *pSeqCmd;
uint32_t SeqLen;
AFERefCfg_Type aferef_cfg;
HSLoopCfg_Type hs_loop;
DSPCfg_Type dsp_cfg;
float sin_freq;
/* Start sequence generator here */
AD5940_SEQGenCtrl(bTRUE);
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 = bFALSE;
aferef_cfg.Lp1V8BuffEn = bFALSE;
/* LP reference control - turn off them to save powr*/
aferef_cfg.LpBandgapEn = bTRUE;
aferef_cfg.LpRefBufEn = bTRUE;
aferef_cfg.LpRefBoostEn = bFALSE;
AD5940_REFCfgS(&aferef_cfg);
hs_loop.HsDacCfg.ExcitBufGain = AppBIOZCfg.ExcitBufGain;
hs_loop.HsDacCfg.HsDacGain = AppBIOZCfg.HsDacGain;
hs_loop.HsDacCfg.HsDacUpdateRate = AppBIOZCfg.HsDacUpdateRate;
hs_loop.HsTiaCfg.DiodeClose = bFALSE;
hs_loop.HsTiaCfg.HstiaBias = HSTIABIAS_1P1;
hs_loop.HsTiaCfg.HstiaCtia = AppBIOZCfg.CtiaSel; /* 31pF + 2pF */
hs_loop.HsTiaCfg.HstiaDeRload = HSTIADERLOAD_OPEN;
hs_loop.HsTiaCfg.HstiaDeRtia = HSTIADERTIA_OPEN;
hs_loop.HsTiaCfg.HstiaRtiaSel = AppBIOZCfg.HstiaRtiaSel;
hs_loop.SWMatCfg.Dswitch = SWD_OPEN;
hs_loop.SWMatCfg.Pswitch = SWP_PL|SWP_PL2;
hs_loop.SWMatCfg.Nswitch = SWN_NL|SWN_NL2;
hs_loop.SWMatCfg.Tswitch = SWT_TRTIA;
hs_loop.WgCfg.WgType = WGTYPE_SIN;
hs_loop.WgCfg.GainCalEn = bFALSE;
hs_loop.WgCfg.OffsetCalEn = bFALSE;
if(AppBIOZCfg.SweepCfg.SweepEn == bTRUE)
{
AppBIOZCfg.SweepCfg.SweepIndex = 0;
AppBIOZCfg.FreqofData = AppBIOZCfg.SweepCfg.SweepStart;
AppBIOZCfg.SweepCurrFreq = AppBIOZCfg.SweepCfg.SweepStart;
AD5940_SweepNext(&AppBIOZCfg.SweepCfg, &AppBIOZCfg.SweepNextFreq);
sin_freq = AppBIOZCfg.SweepCurrFreq;
}
else
{
sin_freq = AppBIOZCfg.SinFreq;
AppBIOZCfg.FreqofData = sin_freq;
}
hs_loop.WgCfg.SinCfg.SinFreqWord = AD5940_WGFreqWordCal(sin_freq, AppBIOZCfg.SysClkFreq);
hs_loop.WgCfg.SinCfg.SinAmplitudeWord = (uint32_t)(AppBIOZCfg.DacVoltPP/800.0f*2047 + 0.5f);
hs_loop.WgCfg.SinCfg.SinOffsetWord = 0;
hs_loop.WgCfg.SinCfg.SinPhaseWord = 0;
AD5940_HSLoopCfgS(&hs_loop);
dsp_cfg.ADCBaseCfg.ADCMuxN = ADCMUXN_HSTIA_N;
dsp_cfg.ADCBaseCfg.ADCMuxP = ADCMUXP_HSTIA_P;
dsp_cfg.ADCBaseCfg.ADCPga = AppBIOZCfg.ADCPgaGain;
memset(&dsp_cfg.ADCDigCompCfg, 0, sizeof(dsp_cfg.ADCDigCompCfg));
dsp_cfg.ADCFilterCfg.ADCAvgNum = ADCAVGNUM_16; /* Don't care becase it's disabled */
dsp_cfg.ADCFilterCfg.ADCRate = ADCRATE_800KHZ; /* Tell filter block clock rate of ADC*/
dsp_cfg.ADCFilterCfg.ADCSinc2Osr = AppBIOZCfg.ADCSinc2Osr;
dsp_cfg.ADCFilterCfg.ADCSinc3Osr = AppBIOZCfg.ADCSinc3Osr;
dsp_cfg.ADCFilterCfg.BpSinc3 = bFALSE;
dsp_cfg.ADCFilterCfg.BpNotch = bTRUE;
dsp_cfg.ADCFilterCfg.Sinc2NotchEnable = bTRUE;
dsp_cfg.DftCfg.DftNum = AppBIOZCfg.DftNum;
dsp_cfg.DftCfg.DftSrc = AppBIOZCfg.DftSrc;
dsp_cfg.DftCfg.HanWinEn = AppBIOZCfg.HanWinEn;
memset(&dsp_cfg.StatCfg, 0, sizeof(dsp_cfg.StatCfg)); /* Don't care about Statistic */
AD5940_DSPCfgS(&dsp_cfg);
/* Enable all of them. They are automatically turned off during hibernate mode to save power */
AD5940_AFECtrlS(AFECTRL_HPREFPWR|AFECTRL_HSTIAPWR|AFECTRL_INAMPPWR|AFECTRL_EXTBUFPWR|\
AFECTRL_DACREFPWR|AFECTRL_HSDACPWR|\
AFECTRL_SINC2NOTCH, bTRUE);
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 extral 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 seuqncer generator */
if(error == AD5940ERR_OK)
{
AppBIOZCfg.InitSeqInfo.SeqId = SEQID_1;
AppBIOZCfg.InitSeqInfo.SeqRamAddr = AppBIOZCfg.SeqStartAddr;
AppBIOZCfg.InitSeqInfo.pSeqCmd = pSeqCmd;
AppBIOZCfg.InitSeqInfo.SeqLen = SeqLen;
/* Write command to SRAM */
AD5940_SEQCmdWrite(AppBIOZCfg.InitSeqInfo.SeqRamAddr, pSeqCmd, SeqLen);
}
else
return error; /* Error */
return AD5940ERR_OK;
}
static AD5940Err AppBIOZSeqMeasureGen(void)
{
AD5940Err error = AD5940ERR_OK;
uint32_t const *pSeqCmd;
uint32_t SeqLen;
uint32_t WaitClks;
SWMatrixCfg_Type sw_cfg;
ClksCalInfo_Type clks_cal;
clks_cal.DataType = DATATYPE_DFT;
clks_cal.DftSrc = AppBIOZCfg.DftSrc;
clks_cal.DataCount = 1L<<(AppBIOZCfg.DftNum+2); /* 2^(DFTNUMBER+2) */
clks_cal.ADCSinc2Osr = AppBIOZCfg.ADCSinc2Osr;
clks_cal.ADCSinc3Osr = AppBIOZCfg.ADCSinc3Osr;
clks_cal.ADCAvgNum = 0;
clks_cal.RatioSys2AdcClk = AppBIOZCfg.SysClkFreq/AppBIOZCfg.AdcClkFreq;
AD5940_ClksCalculate(&clks_cal, &WaitClks);
/* Start sequence generator here */
AD5940_SEQGenCtrl(bTRUE);
AD5940_SEQGpioCtrlS(AGPIO_Pin1/*|AGPIO_Pin5|AGPIO_Pin1*/);//GP6->endSeq, GP5 -> AD8233=OFF, GP1->RLD=OFF .
/* Configure switch matrix to connect the sensor */
sw_cfg.Dswitch = AppBIOZCfg.DswitchSel;
sw_cfg.Pswitch = AppBIOZCfg.PswitchSel;
sw_cfg.Nswitch = AppBIOZCfg.NswitchSel;
sw_cfg.Tswitch = AppBIOZCfg.TswitchSel|SWT_TRTIA;
AD5940_SWMatrixCfgS(&sw_cfg);
AD5940_SEQGenInsert(SEQ_WAIT(16*250));
/* Step 1: Measure Current */
AD5940_ADCMuxCfgS(ADCMUXP_HSTIA_P, ADCMUXN_HSTIA_N);
AD5940_AFECtrlS(AFECTRL_WG|AFECTRL_ADCPWR, bTRUE); /* Enable Waveform generator, ADC power */
AD5940_SEQGenInsert(SEQ_WAIT(16*50));
AD5940_AFECtrlS(AFECTRL_ADCCNV|AFECTRL_DFT, bTRUE); /* Start ADC convert and DFT */
AD5940_SEQGenInsert(SEQ_WAIT(WaitClks)); /* wait for first data ready */
AD5940_SEQGenInsert(SEQ_WAIT(1));
AD5940_AFECtrlS(AFECTRL_ADCCNV|AFECTRL_DFT|AFECTRL_WG|AFECTRL_ADCPWR, bFALSE); /* Stop ADC convert and DFT */
/* Step 2: Measure Voltage */
AD5940_ADCMuxCfgS(ADCMUXP_VCE0, ADCMUXN_N_NODE);
AD5940_AFECtrlS(AFECTRL_WG|AFECTRL_ADCPWR, bTRUE); /* Enable Waveform generator, ADC power */
AD5940_SEQGenInsert(SEQ_WAIT(16*50));
AD5940_AFECtrlS(AFECTRL_ADCCNV|AFECTRL_DFT, bTRUE); /* Start ADC convert and DFT */
AD5940_SEQGenInsert(SEQ_WAIT(WaitClks)); /* wait for first data ready */
AD5940_SEQGenInsert(SEQ_WAIT(1));
AD5940_AFECtrlS(AFECTRL_ADCCNV|AFECTRL_DFT|AFECTRL_WG|AFECTRL_ADCPWR, bFALSE); /* Stop ADC convert and DFT */
sw_cfg.Dswitch = SWD_OPEN;
sw_cfg.Pswitch = SWP_PL|SWP_PL2;
sw_cfg.Nswitch = SWN_NL|SWN_NL2;
sw_cfg.Tswitch = SWT_TRTIA;
AD5940_SWMatrixCfgS(&sw_cfg); /* Float switches */
AD5940_SEQGpioCtrlS(0/*AGPIO_Pin6|AGPIO_Pin5|AGPIO_Pin1*/); //GP6->endSeq, GP5 -> AD8233=OFF, GP1->RLD=OFF .
AD5940_EnterSleepS();/* Goto hibernate */
/* Sequence end. */
error = AD5940_SEQGenFetchSeq(&pSeqCmd, &SeqLen);
AD5940_SEQGenCtrl(bFALSE); /* Stop seuqncer generator */
AppBIOZCfg.MeasSeqCycleCount = AD5940_SEQCycleTime();
AppBIOZCfg.MaxODR = 1/(((AppBIOZCfg.MeasSeqCycleCount + 10) / 16.0)* 1E-6) ;
if(AppBIOZCfg.BIOZODR > AppBIOZCfg.MaxODR)
{
/* We have requested a sampling rate that cannot be achieved with the time it
takes to acquire a sample.
*/
AppBIOZCfg.BIOZODR = AppBIOZCfg.MaxODR;
}
if(error == AD5940ERR_OK)
{
AppBIOZCfg.MeasureSeqInfo.SeqId = SEQID_0;
AppBIOZCfg.MeasureSeqInfo.SeqRamAddr = AppBIOZCfg.InitSeqInfo.SeqRamAddr + AppBIOZCfg.InitSeqInfo.SeqLen ;
AppBIOZCfg.MeasureSeqInfo.pSeqCmd = pSeqCmd;
AppBIOZCfg.MeasureSeqInfo.SeqLen = SeqLen;
/* Write command to SRAM */
AD5940_SEQCmdWrite(AppBIOZCfg.MeasureSeqInfo.SeqRamAddr, pSeqCmd, SeqLen);
}
else
return error; /* Error */
return AD5940ERR_OK;
}
static AD5940Err AppBIOZRtiaCal(void)
{
HSRTIACal_Type hsrtia_cal;
FreqParams_Type freq_params;
if(AppBIOZCfg.SweepCfg.SweepEn == bTRUE)
{
hsrtia_cal.fFreq = AppBIOZCfg.SweepCfg.SweepStart;
freq_params = AD5940_GetFreqParameters(AppBIOZCfg.SweepCfg.SweepStart);
}
else
{
hsrtia_cal.fFreq = AppBIOZCfg.SinFreq;
freq_params = AD5940_GetFreqParameters(AppBIOZCfg.SinFreq);
}
if(freq_params.HighPwrMode == bTRUE)
hsrtia_cal.AdcClkFreq = 32e6;
else
hsrtia_cal.AdcClkFreq = 16e6;
hsrtia_cal.ADCSinc2Osr = freq_params.ADCSinc2Osr;
hsrtia_cal.ADCSinc3Osr = freq_params.ADCSinc3Osr;
hsrtia_cal.DftCfg.DftNum = freq_params.DftNum;
hsrtia_cal.DftCfg.DftSrc = freq_params.DftSrc;
hsrtia_cal.bPolarResult = bTRUE; /* We need magnitude and phase here */
hsrtia_cal.DftCfg.HanWinEn = AppBIOZCfg.HanWinEn;
hsrtia_cal.fRcal= AppBIOZCfg.RcalVal;
hsrtia_cal.HsTiaCfg.DiodeClose = bFALSE;
hsrtia_cal.HsTiaCfg.HstiaBias = HSTIABIAS_1P1;
hsrtia_cal.HsTiaCfg.HstiaCtia = AppBIOZCfg.CtiaSel;
hsrtia_cal.HsTiaCfg.HstiaDeRload = HSTIADERLOAD_OPEN;
hsrtia_cal.HsTiaCfg.HstiaDeRtia = HSTIADERTIA_OPEN;
hsrtia_cal.HsTiaCfg.HstiaRtiaSel = AppBIOZCfg.HstiaRtiaSel;
hsrtia_cal.SysClkFreq = AppBIOZCfg.SysClkFreq;
if(AppBIOZCfg.SweepCfg.SweepEn == bTRUE)
{
uint32_t i;
AppBIOZCfg.SweepCfg.SweepIndex = 0; /* Reset index */
for(i=0;i<AppBIOZCfg.SweepCfg.SweepPoints;i++)
{
AD5940_HSRtiaCal(&hsrtia_cal, &AppBIOZCfg.RtiaCalTable[i]);
#ifdef ADI_DEBUG
ADI_Print("Freq:%.2f, (%f, %f)Ohm\n", hsrtia_cal.fFreq, AppBIOZCfg.RtiaCalTable[i].Real, AppBIOZCfg.RtiaCalTable[i].Image);
#endif
AD5940_SweepNext(&AppBIOZCfg.SweepCfg, &hsrtia_cal.fFreq);
freq_params = AD5940_GetFreqParameters(hsrtia_cal.fFreq);
if(freq_params.HighPwrMode == bTRUE)
{
hsrtia_cal.AdcClkFreq = 32e6;
/* Change clock to 32MHz oscillator */
AD5940_HPModeEn(bTRUE);
}
else
{
hsrtia_cal.AdcClkFreq = 16e6;
/* Change clock to 16MHz oscillator */
AD5940_HPModeEn(bFALSE);
}
hsrtia_cal.ADCSinc2Osr = freq_params.ADCSinc2Osr;
hsrtia_cal.ADCSinc3Osr = freq_params.ADCSinc3Osr;
hsrtia_cal.DftCfg.DftNum = freq_params.DftNum;
hsrtia_cal.DftCfg.DftSrc = freq_params.DftSrc;
}
AppBIOZCfg.SweepCfg.SweepIndex = 0; /* Reset index */
AppBIOZCfg.RtiaCurrValue = AppBIOZCfg.RtiaCalTable[0];
}
else
{
AD5940_HSRtiaCal(&hsrtia_cal, &AppBIOZCfg.RtiaCurrValue);
#ifdef ADI_DEBUG
ADI_Print("Freq:%.2f, (%f, %f)Ohm\n", hsrtia_cal.fFreq, AppBIOZCfg.RtiaCurrValue.Real, AppBIOZCfg.RtiaCurrValue.Image);
#endif
}
return AD5940ERR_OK;
}
/* This function provide application initialize. */
AD5940Err AppBIOZInit(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((AppBIOZCfg.ReDoRtiaCal == bTRUE) || \
AppBIOZCfg.BIOZInited == bFALSE) /* Do calibration on the first initializaion */
{
AppBIOZRtiaCal();
AppBIOZCfg.ReDoRtiaCal = bFALSE;
}
/* Reconfigure FIFO */
AD5940_FIFOCtrlS(FIFOSRC_DFT, 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 = FIFOSRC_DFT;
fifo_cfg.FIFOThresh = AppBIOZCfg.FifoThresh; /* DFT result. One pair for RCAL, another for Rz. One DFT result have real part and imaginary part */
AD5940_FIFOCfg(&fifo_cfg);
AD5940_INTCClrFlag(AFEINTSRC_ALLINT);
/* Start sequence generator */
/* Initialize sequencer generator */
if((AppBIOZCfg.BIOZInited == bFALSE)||\
(AppBIOZCfg.bParaChanged == bTRUE))
{
if(pBuffer == 0) return AD5940ERR_PARA;
if(BufferSize == 0) return AD5940ERR_PARA;
AD5940_SEQGenInit(pBuffer, BufferSize);
/* Generate initialize sequence */
error = AppBIOZSeqCfgGen(); /* Application initialization sequence using either MCU or sequencer */
if(error != AD5940ERR_OK) return error;
/* Generate measurement sequence */
error = AppBIOZSeqMeasureGen();
if(error != AD5940ERR_OK) return error;
AppBIOZCfg.bParaChanged = bFALSE; /* Clear this flag as we already implemented the new configuration */
}
/* Initialization sequencer */
AppBIOZCfg.InitSeqInfo.WriteSRAM = bFALSE;
AD5940_SEQInfoCfg(&AppBIOZCfg.InitSeqInfo);
seq_cfg.SeqEnable = bTRUE;
AD5940_SEQCfg(&seq_cfg); /* Enable sequencer */
AD5940_SEQMmrTrig(AppBIOZCfg.InitSeqInfo.SeqId);
while(AD5940_INTCTestFlag(AFEINTC_1, AFEINTSRC_ENDSEQ) == bFALSE);
AD5940_INTCClrFlag(AFEINTSRC_ALLINT);
/* Measurment sequence */
AppBIOZCfg.MeasureSeqInfo.WriteSRAM = bFALSE;
AD5940_SEQInfoCfg(&AppBIOZCfg.MeasureSeqInfo);
AppBIOZCheckFreq(AppBIOZCfg.FreqofData);
seq_cfg.SeqEnable = bTRUE;
AD5940_SEQCfg(&seq_cfg); /* Enable sequencer, and wait for trigger */
AD5940_ClrMCUIntFlag(); /* Clear interrupt flag generated before */
AppBIOZCfg.BIOZInited = bTRUE; /* BIOZ application has been initialized. */
return AD5940ERR_OK;
}
/* Depending on frequency of Sin wave set optimum filter settings */
AD5940Err AppBIOZCheckFreq(float freq)
{
ADCFilterCfg_Type filter_cfg;
DFTCfg_Type dft_cfg;
HSDACCfg_Type hsdac_cfg;
uint32_t WaitClks;
ClksCalInfo_Type clks_cal;
FreqParams_Type freq_params;
uint32_t SeqCmdBuff[2];
uint32_t SRAMAddr = 0;;
/* Step 1: Check Frequency */
freq_params = AD5940_GetFreqParameters(freq);
/* Set power mode */
if(freq_params.HighPwrMode == bTRUE)
{
/* Update HSDAC update rate */
hsdac_cfg.ExcitBufGain = AppBIOZCfg.ExcitBufGain;
hsdac_cfg.HsDacGain = AppBIOZCfg.HsDacGain;
hsdac_cfg.HsDacUpdateRate = 0x7;
AD5940_HSDacCfgS(&hsdac_cfg);
/*Update ADC rate */
filter_cfg.ADCRate = ADCRATE_1P6MHZ;
AppBIOZCfg.AdcClkFreq = 32e6;
/* Change clock to 32MHz oscillator */
AD5940_HPModeEn(bTRUE);
}else
{
/* Update HSDAC update rate */
hsdac_cfg.ExcitBufGain = AppBIOZCfg.ExcitBufGain;
hsdac_cfg.HsDacGain = AppBIOZCfg.HsDacGain;
hsdac_cfg.HsDacUpdateRate = 0x1B;
AD5940_HSDacCfgS(&hsdac_cfg);
/* Update ADC rate */
filter_cfg.ADCRate = ADCRATE_800KHZ;
AppBIOZCfg.AdcClkFreq = 16e6;
/* Change clock to 16MHz oscillator */
AD5940_HPModeEn(bFALSE);
}
/* Step 2: Adjust ADCFILTERCON and DFTCON to set optimumn SINC3, SINC2 and DFTNUM settings */
filter_cfg.ADCAvgNum = ADCAVGNUM_16; /* Don't care because it's disabled */
filter_cfg.ADCSinc2Osr = freq_params.ADCSinc2Osr;
filter_cfg.ADCSinc3Osr = freq_params.ADCSinc3Osr;
filter_cfg.BpSinc3 = bFALSE;
filter_cfg.BpNotch = bTRUE;
filter_cfg.Sinc2NotchEnable = bTRUE;
dft_cfg.DftNum = freq_params.DftNum;
dft_cfg.DftSrc = freq_params.DftSrc;
dft_cfg.HanWinEn = AppBIOZCfg.HanWinEn;
AD5940_ADCFilterCfgS(&filter_cfg);
AD5940_DFTCfgS(&dft_cfg);
/* Step 3: Calculate clocks needed to get result to FIFO and update sequencer wait command */
clks_cal.DataType = DATATYPE_DFT;
clks_cal.DftSrc = freq_params.DftSrc;
clks_cal.DataCount = 1L<<(freq_params.DftNum+2); /* 2^(DFTNUMBER+2) */
clks_cal.ADCSinc2Osr = freq_params.ADCSinc2Osr;
clks_cal.ADCSinc3Osr = freq_params.ADCSinc3Osr;
clks_cal.ADCAvgNum = 0;
clks_cal.RatioSys2AdcClk = AppBIOZCfg.SysClkFreq/AppBIOZCfg.AdcClkFreq;
AD5940_ClksCalculate(&clks_cal, &WaitClks);
/* Maximum number of clocks is 0x3FFFFFFF. More are needed if the frequency is low */
if(WaitClks > 0x3FFFFFFF)
{
WaitClks /=2;
SRAMAddr = AppBIOZCfg.MeasureSeqInfo.SeqRamAddr;
SeqCmdBuff[0] = SEQ_WAIT(WaitClks);
AD5940_SEQCmdWrite(SRAMAddr+11, SeqCmdBuff, 1);
AD5940_SEQCmdWrite(SRAMAddr+12, SeqCmdBuff, 1);
AD5940_SEQCmdWrite(SRAMAddr+18, SeqCmdBuff, 1);
AD5940_SEQCmdWrite(SRAMAddr+19, SeqCmdBuff, 1);
}
else
{
SRAMAddr = AppBIOZCfg.MeasureSeqInfo.SeqRamAddr;
SeqCmdBuff[0] = SEQ_WAIT(WaitClks);
AD5940_SEQCmdWrite(SRAMAddr+11, SeqCmdBuff, 1);
AD5940_SEQCmdWrite(SRAMAddr+18, SeqCmdBuff, 1);
}
return AD5940ERR_OK;
}
/* Modify registers when AFE wakeup */
static AD5940Err AppBIOZRegModify(int32_t * const pData, uint32_t *pDataCount)
{
if(AppBIOZCfg.NumOfData > 0)
{
AppBIOZCfg.FifoDataCount += *pDataCount/4;
if(AppBIOZCfg.FifoDataCount >= AppBIOZCfg.NumOfData)
{
AD5940_WUPTCtrl(bFALSE);
return AD5940ERR_OK;
}
}
if(AppBIOZCfg.StopRequired == bTRUE)
{
AD5940_WUPTCtrl(bFALSE);
return AD5940ERR_OK;
}
if(AppBIOZCfg.SweepCfg.SweepEn) /* Need to set new frequency and set power mode */
{
AppBIOZCheckFreq(AppBIOZCfg.SweepNextFreq);
AD5940_WGFreqCtrlS(AppBIOZCfg.SweepNextFreq, AppBIOZCfg.SysClkFreq);
}
return AD5940ERR_OK;
}
/* Depending on the data type, do appropriate data pre-process before return back to controller */
static AD5940Err AppBIOZDataProcess(int32_t * const pData, uint32_t *pDataCount)
{
uint32_t DataCount = *pDataCount;
uint32_t ImpResCount = DataCount/4;
fImpCar_Type * pOut = (fImpCar_Type*)pData;
iImpCar_Type * pSrcData = (iImpCar_Type*)pData;
*pDataCount = 0;
DataCount = (DataCount/4)*4; /* One DFT result has two data in FIFO, real part and imaginary part. Each measurement has 2 DFT results, one for voltage measurement, one for current */
/* Convert DFT result to int32_t type */
for(uint32_t i=0; i<DataCount; i++)
{
pData[i] &= 0x3ffff;
if(pData[i]&(1<<17)) /* Bit17 is sign bit */
{
pData[i] |= 0xfffc0000; /* Data is 18bit in two's complement, bit17 is the sign bit */
}
}
for(uint32_t i=0; i<ImpResCount; i++)
{
fImpCar_Type DftCurr, DftVolt;
fImpCar_Type res;
DftCurr.Real = (float)pSrcData[i].Real;
DftCurr.Image = (float)pSrcData[i].Image;
DftVolt.Real = (float)pSrcData[i+1].Real;
DftVolt.Image = (float)pSrcData[i+1].Image;
DftCurr.Real = -DftCurr.Real;
DftCurr.Image = -DftCurr.Image;
DftVolt.Real = DftVolt.Real;
DftVolt.Image = DftVolt.Image;
res = AD5940_ComplexDivFloat(&DftCurr, &AppBIOZCfg.RtiaCurrValue); /* I=Vrtia/Zrtia */
res = AD5940_ComplexDivFloat(&DftVolt, &res);
pOut[i] = res;
}
*pDataCount = ImpResCount;
/* Calculate next frequency point */
if(AppBIOZCfg.SweepCfg.SweepEn == bTRUE)
{
AppBIOZCfg.FreqofData = AppBIOZCfg.SweepCurrFreq;
AppBIOZCfg.SweepCurrFreq = AppBIOZCfg.SweepNextFreq;
AppBIOZCfg.RtiaCurrValue = AppBIOZCfg.RtiaCalTable[AppBIOZCfg.SweepCfg.SweepIndex];
AD5940_SweepNext(&AppBIOZCfg.SweepCfg, &AppBIOZCfg.SweepNextFreq);
}
return AD5940ERR_OK;
}
/**
*/
AD5940Err AppBIOZISR(void *pBuff, uint32_t *pCount)
{
uint32_t BuffCount;
uint32_t FifoCnt;
if(AppBIOZCfg.BIOZInited == bFALSE)
return AD5940ERR_APPERROR;
if(AD5940_WakeUp(10) > 10) /* Wakeup AFE by read register, read 10 times at most */
return AD5940ERR_WAKEUP; /* Wakeup Failed */
AD5940_SleepKeyCtrlS(SLPKEY_LOCK); /* Don't enter hibernate */
*pCount = 0;
if(AD5940_INTCTestFlag(AFEINTC_0, AFEINTSRC_DATAFIFOTHRESH) == bTRUE)
{
/* Now there should be 4 data in FIFO */
FifoCnt = (AD5940_FIFOGetCnt()/4)*4;
AD5940_FIFORd((uint32_t *)pBuff, FifoCnt);
AD5940_INTCClrFlag(AFEINTSRC_DATAFIFOTHRESH);
AppBIOZRegModify(pBuff, &FifoCnt); /* If there is need to do AFE re-configure, do it here when AFE is in active state */
AD5940_EnterSleepS(); /* Manually put AFE back to hibernate mode to save power. */
AD5940_SleepKeyCtrlS(SLPKEY_UNLOCK); /* Allow AFE to enter hibernate mode */
/* Process data */
AppBIOZDataProcess((int32_t*)pBuff,&FifoCnt);
*pCount = FifoCnt;
return 0;
}
return 0;
}
/**
* @}
*/
Hello Akila,
I see the highlighted regions that need to be changed in the BIOZ-2Wire.c file but what should they be changed to in order to obtain the 1000hz sampling rate?
The regions that you have indicated are already present (unedited lines of code) in the BIOZ-2Wire.c file
Thanks
Hi,
You have to give different values to these parameters and check the MaxODR till it reaches best MaxODR.
Hello Akila,
I decided to diverge this question into my other forum to ensure that I don't cause confusion to the individual who asked a similar question with a different example project. Here is the link: How to Increase Sampling Rate For The EVAL-AD5940BIOZ Board (Impedance Measurements)
I understand that I have to change different values in the numerical parameters (what should it be ideally set at to ensure that the accuracy of the data is not affected) and what specific code should the following be changed to in the BIOZ-2Wire.c file :