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//----- Include Files ---------------------------------------------------------#include <avr/io.h> // include I/O definitions (port names, pin names, etc)#include <avr/interrupt.h> // include interrupt support#include <math.h>#include "global.h" // include our global settings#include "uart2.h" // include uart function library#include "rprintf.h" // include printf function library#include "timer.h" // include timer function library (timing, PWM, etc)#include "a2d.h" // include A/D converter function library//----- Begin Code ------------------------------------------------------------#define BUFLEN 64void radtodeg(double fi, u16 *deg, u08 *min, u08 *sec) //convert radians to degrees mins and seconds{double pom;fi=fi*180/PI;*deg=(u16)trunc(fi);pom=(fi-(*deg))*60;*min=(u08)trunc(pom);*sec=(u08)round((pom-(*min))*60);}inline double quadraticerror(double average, double buf[], u16 size) // compute average quadratic error{u16 i;double err=0;for(i=0; i<size; i++) err += square(buf[i]-average); // sum quadratic errorserr = sqrt((1/(double)size)*err);return err;}int main(void){u16 i,x,y;double fi, err, fibuf[BUFLEN]; // buffer for recorded and computed valuesu08 fi_min, fi_sec, err_min, err_sec; // computed anglesu16 fi_deg, err_deg; // computed angles in whole degrees// initialize some libraries// initialize the UART (serial port)uartInit();uartSetBaudRate(0,9600);// make all rprintf statements use uart for outputrprintfInit(uart0SendByte);// initialize the timer systemtimerInit();// turn on and initialize A/D convertera2dInit();// configure a2d port (PORTA) as input// so we can receive analog signalsDDRF = 0x00;// make sure pull-up resistors are turned offPORTF = 0x00;// set the a2d prescaler (clock division ratio)// - a lower prescale setting will make the a2d converter go faster// - a higher setting will make it go slower but the measurements// will be more accurate// - other allowed prescale values can be found in a2d.ha2dSetPrescaler(ADC_PRESCALE_DIV128);// set the a2d reference// - the reference is the voltage against which a2d measurements are made// - other allowed reference values can be found in a2d.ha2dSetReference(ADC_REFERENCE_AREF);// use a2dConvert8bit(channel#) to get an 8bit a2d reading// use a2dConvert10bit(channel#) to get a 10bit a2d readingrprintf("inklinometr 2009\r\n");while(1){fi=0;err=0;for(i=0; i<BUFLEN; i++){x = a2dConvert10bit(ADC_CH_ADC0);y = a2dConvert10bit(ADC_CH_ADC1);fibuf[i] = atan2((double)x-511,(double)y-511); // record computed angles to buffer for post processing}for(i=0; i<BUFLEN; i++) fi += fibuf[i]; // sum recorded anglesfi = (fi/BUFLEN)+PI; // average recorded angles and expand product to whole circleerr=quadraticerror((fi-PI),fibuf,BUFLEN);radtodeg(fi,&fi_deg,&fi_min,&fi_sec); //translate radians to degreesradtodeg(err,&err_deg,&err_min,&err_sec);rprintf("fi:%d.%d.%d +- %d.%d.%d \r\n", fi_deg, fi_min, fi_sec, err_deg, err_min, err_sec);delay_ms(20);}return 0;}