16.5.4 Oversampling
In Oversampling Example, the conversions are started by a software trigger and continued by back-to-back triggers. The number of accumulated conversion results is set to 16. The oversampling process cannot be interrupted by other channel conversions because the ACCBRST bit is set.
Oversampling Example
#include <xc.h>
// The channel output.
long result = 0;
int main(){
//Set up clock for 40Msps operation
clock_ADC_for_40Msps_from_PLL2();
_TRISC8 = 0;
_ANSELC8 = 0;
// In this example channel 0 will be used.
// Oversampling conversion mode.
AD5CH0CON1bits.MODE = 3;
// Set number of conversions accumulated to 16.
AD5CH0CON1bits.ACCNUM = 1;
// The oversampling if started cannot be interrupted
// by a high priority channels conversion requests.
AD5CH0CON2bits.ACCBRST = 1;
// Software trigger will start a conversions.
AD5CH0CON1bits.TRG1SRC = 1;
// Re-trigger back to back.
AD5CH0CON1bits.TRG2SRC = 2;
// Select the AN0 analog positive input/pin.
AD5CH0CON1bits.PINSEL = 0;
// Select signal sampling time (6.5 TADs = 81nS).
AD5CH0CON1bits.SAMC = 3;
// Set ADC to RUN mode.
AD5CONbits.MODE = 2;
// Enable ADC.
AD5CONbits.ON = 1;
// Wait when ADC will be ready/calibrated.
while(AD5CONbits.ADRDY == 0);
// Trigger channel #0 in software and wait for the 16 samples
// oversampling result.
while(1){
// Trigger channel # 0.
AD5SWTRGbits.CH0TRG = 1;
// Wait for a conversion ready flag.
while(AD5STATbits.CH0RDY == 0);
// Read oversampling result. It will clear the conversion ready flag.
result = AD5CH0DATA;
_LATC8 ^= 1;
}
return 1;
}