#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>
#include "lcd.h"
#include "pin.h"
#include "stdint.h"
#include "stdio.h"
#include <string.h>
#include "ds18x20lib.h"
// S T A R T M A I N P R O G R A M
int main (void)
{
// Init display
lcd_init(LCD_DISP_ON);
// Clear screen
lcd_clrscr();
//-----------------------------------------
// Allocate memory
//-----------------------------------------
unsigned char temp_po_str[8],temp_pm_str[8];//,temp_pu_str[8],temp_ke_str[8],temp_bo_str[8];
float temp_po,temp_pm;//temp_pu,temp_ke,temp_bo;
//-----------------------------------------
// Init Stuff
//-----------------------------------------
ds1820_init(DS1820_pin_po); //Initialize DS1820
ds1820_init(DS1820_pin_pm); //Initialize DS1820
//-----------------------------------------
// Do only once
//-----------------------------------------
for(;;){
//-----------------------------------------
// Read temperature
//-----------------------------------------
temp_po = ds1820_read_temp(DS1820_pin_po);//Get temperature from DS1820 puffer oben
temp_pm = ds1820_read_temp(DS1820_pin_pm);//Get temperature from DS1820 puffer mitte
sprintf(temp_po_str,"%.1f C",temp_po); //Convert temp. puffer oben to string
lcd_gotoxy(1,0);
lcd_puts(temp_po_str);
sprintf(temp_pm_str,"%.1f C",temp_pm); //Convert temp. puffer mitte to string
lcd_gotoxy(1,1);
lcd_puts(temp_pm_str);
}
}
// E N D M A I N P R O G R A M
//----------------------------------------
// Reset DS18S20
//----------------------------------------
uint8_t ds1820_reset(uint8_t used_pin)
{
uint8_t err=100;
DS1820_DDR |= 1<<used_pin; // define as ouput
DS1820_PORT &= ~(1<<used_pin); //Pull low
_delay_us(480); ; // 480 us
DS1820_DDR &= ~(1<<used_pin); // define as input
DS1820_PORT |= 1<<used_pin; //Pullup on
_delay_us(66); // 66 us
err = (DS1820_PIN & (1<<used_pin)) >> used_pin; // no presence detect --> err=1 otherwise err=0
_delay_us(240); // 240 us
if( (DS1820_PIN & (1<<used_pin)) == 0 ){ // short circuit --> err=2
err = 2;
}
return err;
}
//-----------------------------------------
// Write one bit to DS18S20
//-----------------------------------------
void ds1820_wr_bit(uint8_t wrbit,uint8_t used_pin)
{
if (wrbit ==0) {
DS1820_DDR |= 1<<used_pin; // define as ouput
DS1820_PORT &= ~(1<<used_pin); //Pull low
_delay_us(60);
DS1820_DDR &= ~(1<<used_pin); // define as input
DS1820_PORT |= 1<<used_pin; //Pullup on
_delay_us(4);
}
if (wrbit ==1) {
DS1820_DDR |= 1<<used_pin; // define as ouput
DS1820_PORT &= ~(1<<used_pin); //Pull low
_delay_us(10);
DS1820_DDR &= ~(1<<used_pin); // define as input
DS1820_PORT |= 1<<used_pin; //Pullup on
_delay_us(54);
}
}
//-----------------------------------------
// Read one bit from DS18S20
//-----------------------------------------
uint8_t ds1820_re_bit(uint8_t used_pin)
{
uint8_t rebit;
DS1820_DDR |= 1<<used_pin; // define as ouput
DS1820_PORT &= ~(1<<used_pin); //Pull low
_delay_us(1);
DS1820_DDR &= ~(1<<used_pin); // define as input
DS1820_PORT |= 1<<used_pin; //Pullup on
_delay_us(10);
rebit = (DS1820_PIN & (1<<used_pin)) >> used_pin; //Read bit
_delay_us(50);
return rebit;
}
//-----------------------------------------
// Read 1 byte from DS18S20
//-----------------------------------------
uint8_t ds1820_re_byte(uint8_t used_pin)
{
uint8_t rebit;
uint8_t rebyte =0x00;
uint8_t i;
for (i=0;i<8;i++)
{
rebit=ds1820_re_bit(used_pin);
//_delay_us(2); //be on the save side
if (rebit==1){
rebyte|=(1<<i);
}
}
return(rebit);
}
//-----------------------------------------
// Write 1 byte to DS18S20
//-----------------------------------------
void ds1820_wr_byte(uint8_t wrbyte,uint8_t used_pin)
{
uint8_t i;
for (i=0; i<8; i++) // writes byte, one bit at a time
{
ds1820_wr_bit((wrbyte & 0b00000001),used_pin);
wrbyte = wrbyte >> 1;
}
_delay_us(5);
}
//-----------------------------------------
// Read temperature
//-----------------------------------------
float ds1820_read_temp(uint8_t used_pin)
{
uint8_t error,i;
uint16_t j=0;
uint8_t scratchpad[9];
float temp=0;
scratchpad[0]=0;
scratchpad[1]=0;
scratchpad[2]=0;
scratchpad[3]=0;
scratchpad[4]=0;
scratchpad[5]=0;
scratchpad[6]=0;
scratchpad[7]=0;
scratchpad[8]=0;
error=ds1820_reset(used_pin); //1. Reset
if (error==0){
ds1820_wr_byte(0xCC,used_pin); //2. skip ROM
ds1820_wr_byte(0x44,used_pin); //3. ask for temperature conversion
while (ds1820_re_byte(used_pin)==0xFF && j<1000){ //4. wait until conversion is finished
_delay_us(1);
j++;
}
error=ds1820_reset(used_pin); //5. Reset
ds1820_wr_byte(0xCC,used_pin); //6. skip ROM
ds1820_wr_byte(0xBE,used_pin); //7. Read entire scratchpad 9 bytes
for (i=0; i<9; i++) //8. Get scratchpad byte by byte
{
scratchpad[i]=ds1820_re_byte(used_pin); //9. read one DS18S20 byte
}
}
if(scratchpad[1]==0x00 && scratchpad[7]!=0){ //Value pos.
scratchpad[0]=scratchpad[0] >> 1;
temp=(scratchpad[0]-0.25f+(((float)scratchpad[7]-(float)scratchpad[6])/(float)scratchpad[7]));
temp = (floor(temp*10.0+0.5)/10); //Round value .x
}
if(scratchpad[1]!=0x00){ //Value negative
uint8_t tmp;
tmp =scratchpad[0]; //Save Kommabit
tmp= ~ tmp;
tmp= tmp >> 1;
temp = (-1)*(tmp+1);
if ((scratchpad[0]&0b00000001)==1){
temp=temp+0.5;
}
}
return temp;
}
//-----------------------------------------
// Initialize DS18S20
//-----------------------------------------
void ds1820_init(uint8_t used_pin)
{
uint8_t error;
uint16_t i =0;
error=ds1820_reset(used_pin); //1. Reset
if (error==0){
ds1820_wr_byte(0xCC,used_pin); //2. skip ROM
ds1820_wr_byte(0x44,used_pin); //3. ask for temperature conversion
while (ds1820_re_byte(used_pin)==0xFF && i<1000){ //4. wait until conversion is finished
_delay_us(1);
i++;
}
error=ds1820_reset(used_pin); //5. Reset
ds1820_wr_byte(0xCC,used_pin); //6. skip ROM
ds1820_wr_byte(0xBE,used_pin); //7. Read entire scratchpad 9 bytes
}
}
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