digital-thermometer/src/digital_thermometer.c

97 lines
2.2 KiB
C

/**
* (C) Copyright Collin J. Doering 2015
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* File: digital_thermometer.c
* Author: Collin J. Doering <collin.doering@rekahsoft.ca>
* Date: Oct 28, 2015
*/
/*---------.
| Includes |
`---------*/
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/power.h>
#include <util/delay.h>
#include <stdlib.h>
#include "lcdLib.h"
#include "ansi_escapes.h"
void initADC(void) {
ADMUX |= (1 << REFS0); // reference voltage on AVCC
ADCSRA |= (1 << ADPS2) | (1 << ADPS1); // ADC prescaler 64
ADCSRA |= (1 << ADEN); // Enable ADC
ADCSRA |= (1 << ADATE); // Auto trigger enable
ADCSRA |= (1 << ADSC); // Start first conversion
}
int main(void) {
clock_prescale_set(clock_div_1); // Use 8Mhz internal oscillator
initLCD();
initADC();
hideCursor();
writeStringToLCD("Temperature: ");
saveCursorPosition();
while (1) {
float v = ADC * (5000 / 1024);
int8_t t = (int8_t) ((v - 500) / 10);
char str[5];
uint8_t i = 1, sigDig = 0;
if (t < 0) {
str[0] = '-';
t *= -1;
} else {
str[0] = '+';
}
for (uint8_t j = 100; j >= 1; j /= 10) {
uint8_t digit = (uint8_t) (t / j);
if (!sigDig) {
if (digit != 0) {
sigDig = 1;
str[i++] = digit + 0x30;
} else {
str[i++] = ' ';
}
} else {
str[i++] = digit + 0x30;
}
t = t - digit*j;
}
str[i] = '\0';
writeStringToLCD(str);
writeCharToLCD(0xdf);
writeStringToLCD("C");
restoreCursorPosition();
_delay_ms(16);
}
return 0;
}