Page 212 - Programming Microcontrollers in C

Analog-to-Digital Converter Operation 197

#include “hc05b6.h”

unsigned adc_data[8];
unsigned read_adc(int);

main()
{
unsigned int j;

AD_CTST=0;
AD_CTST.ADON=1;

for(j=0;j<8;j++)
{
adc_data[j]=(read_adc(j)+adc_data[j])/2;
adc_data[j] >>= 1;
adc_data[j] += read_adc(j)>>1;

#asm
ldx j
lda j
jsr read_adc
add adc_data,x
rora
sta adc_data,x
#endasm

}

}

Listing 4-5: Three Different ADC Averaging Routines
The first attempt to read and average the data approaches the
problem as simple as practical. The data are read in from the ADC,
added to the corresponding stored data in the array adc_data, the
result is divided by two, and the final average is put back into the
proper location in the array. The following line of code is all that is
necessary to accomplish this task: