#include <avr/io.h>
#include <avr/eeprom.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>

#define F_CPU 1000000UL  // 1 MHz
#include <util/delay.h>


void delay_us(uint16_t t)
{
  int i;
  if (t > 10)
    for (i=0;i<t/10;i++)
      _delay_us(10);
  else
    _delay_us(t);
}

void delay_ms(uint16_t t)
{
  int i;
  if (t > 10)
    for (i=0;i<t/10;i++)
      _delay_ms(10);
  else
    _delay_ms(t);
}

int ds_reset()
{
  int r=0;
  PORTA &= ~(1<<4);
  DDRA |= (1<<4);        // DQ = 0;
  delay_us(500);        // 480us minimum
  DDRA &= ~(1<<4);        // DQ in
  delay_us(80);            // waits 15-60us and then
  r = (PINA & (1<<4));    //   capture the presence pulse (60-240us)
  delay_us(400);        
  return !r;
}

    \note When using _delay_us() and _delay_ms(), the expressions
    passed as arguments to these functions shall be compile-time
    constants, otherwise the floating-point calculations to setup the
    loops will be done at run-time, thereby drastically increasing
    both the resulting code size, as well as the time required to
    setup the loops.

#include <avr/io.h>
#include <avr/eeprom.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>

#define F_CPU 1000000UL  // 1 MHz
#include <util/delay.h>


void delay_ms(uint16_t t)
{
  uint8_t i;
  if (t > 10)
    for (i=0;i<t/10;i++)
      _delay_ms(10);
  else
    _delay_ms(t);
}

int ds_reset()
{
  uint8_t r=0;
  PORTA &= ~(1<<4);
  DDRA |= (1<<4);        // DQ = 0;
  _delay_us(480);
  DDRA &= ~(1<<4);        // DQ pull up
  _delay_us(70);
  r = (PINA & (1<<4));    // Capture the presence pulse
  _delay_us(410);        
  return !r;
}

void ds_write_bit(uint8_t b)
{
  if (b)
    {
        PORTA &= ~(1<<4);
      DDRA |= (1<<4);        // DQ = 0;
        _delay_us(6);
        DDRA &= ~(1<<4);        // DQ pull up
        _delay_us(64);    
    }
  else
    {
      PORTA &= ~(1<<4);
      DDRA |= (1<<4);        // DQ = 0;
      _delay_us(60);
      DDRA &= ~(1<<4);        // DQ pull up
      _delay_us(10);
    };
}

uint8_t ds_read_bit()
{
  uint8_t r=0;
  PORTA &= ~(1<<4);
  DDRA |= (1<<4);        // DQ = 0;
  _delay_us(6);
  DDRA &= ~(1<<4);        // DQ pull up
  _delay_us(9);
  r = (PINA & (1<<4));
  _delay_us(55);
  if (r)
    return 1;
  else
    return 0;
}

void ds_write_byte(uint8_t data)
{
  uint8_t loop;
  // Loop to write each bit in the byte, LS-bit first
  for (loop = 0; loop < 8; loop++)
    {
      ds_write_bit(data & 0x01);
      // shift the data byte for the next bit
      data >>= 1;
    }
}

uint8_t ds_read_byte()
{
  uint8_t loop, result=0;
  for (loop = 0; loop < 8; loop++)
    {
      // shift the result to get it ready for the next bit
      result >>= 1;
      // if result is one, then set MS bit
      if (ds_read_bit())
        result |= 0x80;
    }
  return result;
}

int16_t ds_read_temperature()
{
  int16_t r = -1;
  int i;
  uint8_t buf[9]={0};

  if (ds_reset())
    {
      ds_write_byte(0xCC);    //Skip ROM command
      ds_write_byte(0x44);    //Convert T command
      delay_ms(1000);        // lame :)
      ds_write_byte(0xBE);    //Read Scratchpad
      for (i=0; i < 10; i++)
        buf[i] = ds_read_byte();
      r = (buf[0] | (buf[1] << 8)) >> 4;

    };
  return r;
}

void delay_ms(uint16_t t)
{
   uint8_t i;
   if (t > 10)
      for (i=t/10;i;i--)
         _delay_ms(10);
      else
         _delay_ms(t);
}

void delay_ms(uint16_t t)
{
   uint8_t i;
   if (t >= 256)
   {
      for (i=t/256;i;i--)
         _delay_ms(256);
      t &= 255;
   }
   _delay_ms(t);
}

int ow_reset()
{
  uint8_t r=0;
  PORTA &= ~(1<<4); // +4.95В
  DDRA |= (1<<4);        // DQ = 0;
r = (PORTA & (1<<4));    //+4.28В        как такое может быть???
  _delay_us(480);
  DDRA &= ~(1<<4);        // DQ pull up
  _delay_us(70);
  r = (PORTA & (1<<4));    // Capture the presence pulse
  _delay_us(410);        
  return r;                        // +4.95В
}

#include <mega16.h>
// 1 Wire Bus functions
#asm
   .equ __w1_port=0x1B;PORTA
   .equ __w1_bit=4
#endasm
#include <1wire.h>
#include <ds18b20.h>
#include <stdio.h>
void main(void)
{
// USART initialization
UCSRA=0x00;
UCSRB=0x08;
UCSRC=0x86;
UBRRH=0x00;
UBRRL=0x0C;

// 1 Wire Bus initialization
w1_init();
if (ds18b20_init(NULL,0,0,DS18B20_12BIT_RES))
  {
     while (1)
      {
      /* measure and display the temperature(s) */
          printf("t=%+.3f\xf8C\n\r",
          ds18b20_temperature(NULL));
      };
  }
else
  printf("error!");

while (1);
}

/* Multipoint thermometer with LCD display
   using the Maxim DS18B20
   1 Wire bus temperature sensors

   CodeVisionAVR C Compiler
   (C) 2000-2005 HP InfoTech S.R.L.
   www.hpinfotech.ro

   Chip: ATmega8515
   Memory Model: SMALL
   Data Stack Size: 128 bytes
  
   THE ATmega8515 CLOCK FREQUENCY MUST BE 3.6864 MHz

   The DS18B20 sensors are connected to
   bit 6 of PORTA of the ATmega8515 as follows:

   [DS18B20]     [STK500 PORTA HEADER]
    1 GND         -   9  GND
    2 DQ          -   7  PA6
    3 VDD         -  10 +5V

   All the temperature sensors must be connected
   in parallel
  
   AN 4.7k PULLUP RESISTOR MUST BE CONNECTED
   BETWEEN DQ (PA6) AND +5V !
*/
#asm
    .equ __w1_port=0x1b
    .equ __w1_bit=6
#endasm

/* Use an 2x16 alphanumeric LCD connected
   to PORTC as follows:

  [LCD]   [STK500 PORTC HEADER]
   1 GND- 9  GND
   2 +5V- 10 VCC  
   3 VLC- LCD contrast control voltage 0..1V
   4 RS - 1  PC0
   5 RD - 2  PC1
   6 EN - 3  PC2
  11 D4 - 5  PC4
  12 D5 - 6  PC5
  13 D6 - 7  PC6
  14 D7 - 8  PC7
*/

#asm
    .equ __lcd_port=0x15
#endasm

#include <lcd.h> // LCD driver routines
#include <ds18b20.h>
#include <delay.h>
#include <stdio.h>

char lcd_buffer[33];

/* maximum number of DS18B20 connected to the 1 Wire bus */
#define MAX_DEVICES 8

/* DS18B20 devices ROM code storage area */
unsigned char rom_code[MAX_DEVICES][9];

main()
{
unsigned char i,j,devices;

lcd_init(16);
lcd_putsf("CodeVisionAVR\n1 Wire Bus Demo");
delay_ms(2000);
lcd_clear();

/* detect how many DS18B20 devices
   are connected to the 1 Wire bus */
devices=w1_search(0xf0,rom_code);
sprintf(lcd_buffer,"%u DS18B20\nDevice detected",devices);
lcd_puts(lcd_buffer);
delay_ms(2000);

/* display the ROM codes for each device */
if (devices)
   {
   for (i=0;i<devices;i++)
       {
       sprintf(lcd_buffer,"Device #%u ROM\nCode is:",i+1);
       lcd_clear();
       lcd_puts(lcd_buffer);
       delay_ms(2000);
       lcd_clear();
       for (j=0;j<8;j++)
           {
           sprintf(lcd_buffer,"%02X ",rom_code[i][j]);
           lcd_puts(lcd_buffer);
           if (j==3) lcd_gotoxy(0,1);
           };
       delay_ms(5000);
       };
   }
else
while (1); /* stop here if no devices were found */

/* configure each DS18B20 device for 12 bit temperature
   measurement resolution */
for (i=0;i<devices;)
    if (!ds18b20_init(&rom_code[i++][0],20,30,DS18B20_12BIT_RES))
       {
       sprintf(lcd_buffer,"Init error for\ndevice #%u",i);
       lcd_clear();
       lcd_puts(lcd_buffer);
       while (1); /* stop here if init error */
       };

/* measure and display the temperature(s) */      
while (1)
      {
      j=1;
      for (i=0;i<devices;i++)
          {
          sprintf(lcd_buffer,"t%u=%+.3f\xdfC",j++,ds18b20_temperature(&rom_code[i][0]));
          lcd_clear();
          lcd_puts(lcd_buffer);
          delay_ms(500);
          };
      };
}