#include #define ADC_DEV "/dev/adc0" int main(void) { unsigned char adc_val[2]; FILE *fp; float voltage; int val; printf("Content-type: text/html\n\n"); printf(""); printf(""); printf("ADC TEST"); printf(""); printf(""); fp = fopen( ADC_DEV, "r" ); if( fp != NULL ) { fread( adc_val, 1, 2, fp ); fclose (fp); int val = (adc_val[0] << 8) | adc_val[1]; voltage = (val * 5.0) / 1023; printf( "ADC channel0 = %f\n" , voltage ); } printf("
"); printf(""); return 0; }