#include <htc.h>
#include <stdio.h>

#define _XTAL_FREQ 4000000

// Fuse bity
__CONFIG(FOSC_INTOSCIO & WDTE_OFF & PWRTE_OFF & MCLRE_OFF & BOREN_OFF & LVP_OFF & CPD_OFF & CP_OFF);

// Inicializace
void init() {
	OPTION_REG = 0b01111111;
	TRISB = 0b11000000;
}

// 1-Wire: RESET
char oneWireReset() {
	char b;
	TRISB6 = 0;
	RB6 = 0;
	__delay_us(480);
	TRISB6 = 1;
	__delay_us(70);
	b = RB6;
	__delay_us(410);
	return b;
}

// 1-Wire: READ BIT
char oneWireReadBit() {
	char b;
	TRISB6 = 0;	
	RB6 = 0;
	__delay_us(6);
	TRISB6 = 1;
	__delay_us(9);
	b = RB6;
	__delay_us(55);
	return b;	
}

// 1-Wire: READ BYTE
char oneWireReadByte() {
	char byte = 0;
	TRISA6 = 0;
	for(char i = 0; i < 8; i++) {
		byte >>= 1;
		if (oneWireReadBit() == 1) {
			byte |= 0b10000000;
		}
	}
	return byte;
}

// 1-Wire: WRITE BIT
void oneWireWriteBit(char b) {
	TRISA6 = 0;
	RB6 = 0;
	if (b != 0) {
		__delay_us(6);
		TRISB6 = 1;
		__delay_us(64);
	} else {
		__delay_us(60);
		TRISB6 = 1;
		__delay_us(10);
	}
}

// 1-Wire: WRITE BYTE
void oneWireWriteByte(char byte) {
	for (char i = 0; i < 8; i++) {
		oneWireWriteBit(byte & 0b00000001);
		byte >>= 1;
	}
}
 
// Hlavni program
void main() {

	unsigned char byteL, byteH;
	unsigned char string[16];

	if (oneWireReset()) {
		printString(1,"DS18B20: X"); 
	} else {
		printString(1,"DS18B20: OK");
	}

	oneWireReset();
	oneWireWriteByte(0xCC);
	oneWireWriteByte(0x44);
	__delay_ms(250);
	__delay_ms(250);
	__delay_ms(250);
	oneWireReset();
	oneWireWriteByte(0xCC);
	oneWireWriteByte(0xBE);
	byteL = oneWireReadByte();
	byteH = oneWireReadByte();
	oneWireReset();
	sprintf(string,"%X %X",byteL,byteH);
	printString(2,string);

	while (1) {
	}

}