Temperature Data Logger part 4

C-Program CODE

#include <p18F4550.h>

#include<stdio.h>

#include "delayy.h"

#include "DS1820.h"

#include "serTr.h"

#include "VI.h"

#define TRUE 1;

#define FALSE 0;

typedef unsigned char bool;

typedef unsigned char uint8;

static uint8 ROM_NO[8];

static uint8 LastDiscrepancy;

static uint8 LastDeviceFlag;

void DS1820(void);

void FindDevices(void);

uint8 OWFirst(void);

uint8 OWSearch(void);

void main()

{

int r;

TXSTA = 0x20; // for asynchronous , tx enable settings

SPBRG = 18; // for 12mhz baud rate.

TXSTAbits.TXEN = 1;

RCSTAbits.SPEN = 1;

for(r=0;r<10;r++)

DS1820_DelayUs(10000); //1sec delay

DS1820(); // this function also contains V and I calling functions

}

/*****************************************/

void DS1820(void)

{

uint8 rslt, i,j;

uint8 All_ROM[5][8];

int r,tem[9];

int cnt;

cnt = 0;

rslt = OWFirst();

if (!DS1820_Reset())

{

while (rslt) // performing search of all the DS connected

{

for(i=0;i<8;i++){

All_ROM[cnt][i]=ROM_NO[i]; // store the current ROM address found in All_Rom[][]

}

cnt++;

rslt = OWSearch(); // search for next ROM address

} // while is closed when all ROMs are found

} // if closed, indicating Search Rom Algorithm is completed

// cnt has the no. of DS IC found

for(j=0;j<6;j++){

for(i=0;i<cnt;i++){ // performing conversion of Temperature for

ConvTemp(&All_ROM[i][0]); // removing error values for all DS ICs

DS1820_DelayUs(10);

ReadTemp(&tem[0],&All_ROM[i][0],i);

DS1820_DelayUs(10);

DS1820_DelayUs(2000);

}

}

while(1){

for(i=0;i<cnt;i++){

// performing Temperature conversion and

// serial send of the Temp readings for all DS ICs

ConvTemp(&All_ROM[i][0]);

DS1820_DelayUs(1);

ReadTemp(&tem[0],&All_ROM[i][0],i);

DS1820_DelayUs(100);

DispTemp(&tem[0],i,&All_ROM[i][0]);

DS1820_DelayUs(20000);

} // FOR DS1820 Temp

} // whil(1) closed

} //ds1820 closed

/*****************************************/

// FIND DEVICES

uint8 OWFirst(void)

{

// reset the search state

LastDiscrepancy = 0;

LastDeviceFlag = FALSE;

return OWSearch();

}

/******************************************************************************/

uint8 OWSearch(void)

{

int id_bit_number,x;

unsigned char last_zero, rom_byte_number, search_result;

int id_bit, cmp_id_bit;

unsigned char rom_byte_mask, search_direction;

// initialize for search

id_bit_number = 1;

last_zero = 0;

rom_byte_number = 0;

rom_byte_mask = 1;

search_result = 0;

// if the last call was not the last one

if (!LastDeviceFlag)

{

// 1-Wire reset

if (DS1820_Reset())

{

SerTx(' ');

SerTx('R');

SerTx('S');

// reset the search

LastDiscrepancy = 0;

LastDeviceFlag = FALSE;

return FALSE;

}

// issue the search command

DS1820_WriteByte(0xF0);

// loop to do the search

do

{

id_bit=0;

cmp_id_bit=0;

if(DS1820_ReadBit()==1) id_bit = 1;

Delay(3);

if(DS1820_ReadBit()==1) cmp_id_bit= 1;

// check for no devices on 1-wire

if ((id_bit == 1) && (cmp_id_bit == 1))

{

break;

}

else {

// all devices coupled have 0 or 1

if (id_bit != cmp_id_bit) {

search_direction = id_bit; // bit write value for search

}

else {

// if this discrepancy if before the Last Discrepancy

// on a previous next then pick the same as last time

if (id_bit_number < LastDiscrepancy)

search_direction = ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0);

else

// if equal to last pick 1, if not then pick 0

search_direction = (id_bit_number == LastDiscrepancy);

// if 0 was picked then record its position in LastZero

if (search_direction == 0)

last_zero = id_bit_number;

} // 2ND ELSE CLOSED

// set or clear the bit in the ROM byte rom_byte_number

// with mask rom_byte_mask

if (search_direction == 1)

ROM_NO[rom_byte_number] |= rom_byte_mask;

else

ROM_NO[rom_byte_number] &= ~rom_byte_mask;

// serial number search direction write bit

DS1820_WriteBit(search_direction);

// increment the byte counter id_bit_number

// and shift the mask rom_byte_mask

id_bit_number++;

rom_byte_mask <<= 1;

// if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask

if (rom_byte_mask == 0)

{

rom_byte_number++;

rom_byte_mask = 1;

}

}

}

while(rom_byte_number < 8); // loop until through all ROM bytes 0-7

// if the search was successful then

if (!(id_bit_number < 65))

{

// search successful so set LastDiscrepancy,LastDeviceFlag,search_result

LastDiscrepancy = last_zero;

// check for last device

if (LastDiscrepancy == 0)

LastDeviceFlag = TRUE;

search_result = TRUE;

}

}

// if no device found then reset counters so next 'search' will be like a first

if (!search_result || !ROM_NO[0])

{

LastDiscrepancy = 0;

LastDeviceFlag = FALSE;

search_result = FALSE;

}

return search_result;

}