////////////////////////////////////////////////////////////////////////////
//// Library for a Dallas 1820 Temperature chip ////
//// ////
//// init_temp(); Call before the other functions are used ////
//// ////
//// ////
//// d = read_full_temp(); Read the temp in degrees C (0 to 125) ////
//// ////
////////////////////////////////////////////////////////////////////////////
#ifndef DS1820_PIN
#define DS1820_PIN PIN_B0
#endif
#define TOUCH_PIN DS1820_PIN
#include "touch.c"
void init_temp() {
}
float read_full_temp()
{
byte i, buffer[9];
float minstep;
if (touch_present()) { // get present (reset) (2)
touch_write_byte(0xCC); // Skip ROM (3)
touch_write_byte (0x44); // Start Conversion
delay_ms(200); // delay 200 ms (4)
touch_present(); // get present (reset) (5)
touch_write_byte(0xCC); // Skip ROM (6)
touch_write_byte (0xBE); // Read Scratch Pad
for(i=0; i<9;i++) // read 9 bytes (7)
buffer[i] = touch_read_byte();
}
//minstep = (float)(buffer[0]/2)-0.25+((float)( buffer[7]-buffer[6])/buffer[7]);
if(buffer[1]){
minstep = (float)(-1)*(~make16(buffer[1],buffer[0])+1)/2;
}else{
minstep = (float)(make16(buffer[1],buffer[0])/2);
}
minstep = minstep - 0.25 + ((float)( buffer[7] - buffer[6])/buffer[7]);
return (minstep);
}
#include <16F876.h> //Standard header file
#fuses NOWDT,HS, NOPUT, NOPROTECT,NOLVP,BROWNOUT //Oscillator mode HS
#use delay(clock=20000000) //Clock speed HZ = 20MHZ
#define use_portd_lcd //define for use port d lcd
#define DS1820_PIN PIN_A2
#define use_portb_lcd TRUE
#include "lcd.c"
#include "ds1820.c"
void main() {
float minstep;
int16 a;
int b;
lcd_init();
do {
minstep = read_full_temp();
printf (lcd_putc,"\fTemp :%3.2f C", minstep);
delay_ms(1000);
} while (TRUE);
}
siempre me esta mostrando -0.25ºC o 2,75º..
#include <termometro.h>
#include <HDM64GS12.c>
#include <graphics_1.c>
#include <1wire.c>
#include <ds1820.c>
#include <eeprom.c>
int8 Pro[]= "PROYECTO";
int8 Ter[]= "TERMOMETRO";
float temperatura_antigua ;
float temperatura_nueva ;
char palabra [16],palabra2 [16];
int8 guar[]= "Guardando";
int8 tempe[]= "Temperatura";
int8 trans[]= "Transmitiendo...";
float resultado;
void main()
{
setup_comparator(NC_NC_NC_NC);// This device COMP currently not supported by the PICWizard
glcd_init(ON);
delay_ms(20);
glcd_rect(10,10,110,58,no,on);
glcd_rect(18,18,68,28,no,on);
glcd_rect(38,38,100,48,no,on);
glcd_text57(20,20,Pro,1,on);
glcd_text57(40,40,Ter,1,on);
delay_ms(1500);
glcd_fillScreen(0);
glcd_rect(10,25,110,42,no,on);
while (1) {
temperatura_nueva = ds1820_read (); // Se vuelve a leer el sensor y este valor se escribe
// en una nueva variable
if (temperatura_nueva != temperatura_antigua){ // Se compara la temperatura vieja con la nueva
glcd_rect(50,30,105,40,yes,OFF); // Se borra la temperatura vieja
sprintf(palabra,"TEMP = %3.1f &C",temperatura_nueva); // Se vuelve a crear un array de valores
glcd_text57(15, 30,palabra, 1, ON);
temperatura_antigua = temperatura_nueva ;
}
if (input(PIN_A0)){
glcd_text57(2, 10,guar, 1, ON);
glcd_text57(60, 10,tempe, 1, ON);
guardar(temperatura_nueva,0);
delay_ms(1500);
glcd_rect(2,10,126,20,yes,off);
}
if (input(PIN_A1)){
glcd_text57(10,50,trans,1,on);
delay_ms(1500);
leer(resultado,0);
sprintf(palabra2,"Temperatura = %f",resultado);
printf (palabra2);
glcd_rect(10,50,110,60,yes,off);
}
}
}
// (C) copyright 2003 j.d.sandoz / jds-pic !at! losdos.dyndns.org
// released under the GNU GENERAL PUBLIC LICENSE (GPL)
// refer to http://www.gnu.org/licenses/gpl.txt
// 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 2 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, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
/***********************1Wire Class***********************/
/*Description: This class handles all communication */
/* between the processor and the 1wire */
/* sensors.
/*********************************************************/
/*-------1-wire definitions-------*/
#define ONE_WIRE_PIN PIN_C2
/*******************1-wire communication functions********************/
/************onewire_reset*************************************************/
/*This function initiates the 1wire bus */
/* */
/*PARAMETERS: */
/*RETURNS: */
/*********************************************************************/
void onewire_reset() // OK if just using a single permanently connected device
{
output_low(ONE_WIRE_PIN);
delay_us( 500 ); // pull 1-wire low for reset pulse
output_float(ONE_WIRE_PIN); // float 1-wire high
delay_us( 500 ); // wait-out remaining initialisation window.
output_float(ONE_WIRE_PIN);
}
/*********************** onewire_write() ********************************/
/*This function writes a byte to the sensor.*/
/* */
/*Parameters: byte - the byte to be written to the 1-wire */
/*Returns: */
/*********************************************************************/
void onewire_write(int data)
{
int count;
for (count=0; count<8; ++count)
{
output_low(ONE_WIRE_PIN);
delay_us( 2 ); // pull 1-wire low to initiate write time-slot.
output_bit(ONE_WIRE_PIN, shift_right(&data,1,0)); // set output bit on 1-wire
delay_us( 60 ); // wait until end of write slot.
output_float(ONE_WIRE_PIN); // set 1-wire high again,
delay_us( 2 ); // for more than 1us minimum.
}
}
/*********************** read1wire() *********************************/
/*This function reads the 8 -bit data via the 1-wire sensor. */
/* */
/*Parameters: */
/*Returns: 8-bit (1-byte) data from sensor */
/*********************************************************************/
int onewire_read()
{
int count, data;
for (count=0; count<8; ++count)
{
output_low(ONE_WIRE_PIN);
delay_us( 2 ); // pull 1-wire low to initiate read time-slot.
output_float(ONE_WIRE_PIN); // now let 1-wire float high,
delay_us( 8 ); // let device state stabilise,
shift_right(&data,1,input(ONE_WIRE_PIN)); // and load result.
delay_us( 120 ); // wait until end of read slot.
}
return( data );
}
float ds1820_read()
{
int8 busy=0, temp1, temp2;
signed int16 temp3;
float result;
onewire_reset();
onewire_write(0xCC);
onewire_write(0x44);
delay_ms (750);
while (busy == 0)
busy = onewire_read();
onewire_reset();
onewire_write(0xCC);
onewire_write(0xBE);
temp1 = onewire_read();
temp2 = onewire_read();
temp3 = make16(temp2, temp1);
//result = (float) temp3 / 2.0; //Calculation for DS18S20 with 0.5 deg C resolution
result = (float) temp3 / 16.0; //Calculation for DS18B20 with 0.1 deg C resolution
delay_ms(200);
return(result);
}
Hola a todos, bueno estube viendo este hilo y me parecio muy interesante, aunque lamentablemente
no cuento con este sensor pero bueno no interesa la idea es aprender como funciona, ademas cuento
con Proteus y sobra decir que es mucha ayuda. Asi que me puse a simular ambos codigos y pude notar
las siguientes diferencias:
- El codigo que compartio micro pepe tiene una respueta mas corta.
- El segundo codigo de maxluis posee un error de conversión que lo hace menos preciso.
Ademas introducion una interrupción en funcion a TMR1 como lo comento MLO y funciona correctamente
eso para comprobar lo que comentaron antes.
Quiero recalcar que todo esto lo comento en función a los resultados obtenidos en simulación.
No obstante como comento el amigo Cryn o alguien quien posea este sensor podria confirmar o no
lo dicho anteriormente.
Adjunto la simulación en Proteus para que alguno pueda verla y comente.
Gracias a todos por compartir conocimientos.....KCIRE
NOTA.- Utilizo la versión 7.2 SP6 de Proteus
(http://img185.imageshack.us/img185/151/ds1820xa7.png)
buenos dias a todos lo ingenieros y estudiante de electronica..
les comparto este proyecto basado en este post la modificacion del termometro de ds18s20 full programado en pic16f877A.
Aqui se los dejo
gracias a todos....
.......
#include "D:\Proyectos electronica\DS18B20 2015\codigo_0_0_0_0_3\main.h"
////////////////////////////////////////////////////////////////////////////
//// Library for a Dallas 1820 Temperature chip ////
//// ////
//// init_temp(); Call before the other functions are used ////
//// ////
//// ////
//// d = read_full_temp(); Read the temp in degrees C (0 to 125) ////
//// ////
////////////////////////////////////////////////////////////////////////////
#ifndef DS1820_PIN
#define DS1820_PIN PIN_B0
#endif
#define TOUCH_PIN DS1820_PIN
#include "touch.c"
void init_temp() {
}
float read_full_temp()
{
byte i, buffer[9];
float minstep;
if (touch_present()) { // get present (reset) (2)
touch_write_byte(0xCC); // Skip ROM (3)
touch_write_byte (0x44); // Start Conversion
delay_ms(200); // delay 200 ms (4)
touch_present(); // get present (reset) (5)
touch_write_byte(0xCC); // Skip ROM (6)
touch_write_byte (0xBE); // Read Scratch Pad
for(i=0; i<9;i++) // read 9 bytes (7)
buffer[i] = touch_read_byte();
}
//minstep = (float)(buffer[0]/2)-0.25+((float)( buffer[7]-buffer[6])/buffer[7]);
if(buffer[1]){
minstep = (float)(-1)*(~make16(buffer[1],buffer[0])+1)/2;
}else{
minstep = (float)(make16(buffer[1],buffer[0])/2);
}
minstep = minstep - 0.25 + ((float)( buffer[7] - buffer[6])/buffer[7]);
return (minstep);
}
#fuses NOWDT,HS, NOPUT, NOPROTECT,NOLVP,BROWNOUT //Oscillator mode HS
//#use delay(clock=40000000) //Clock speed HZ = 20MHZ
#define use_portd_lcd //define for use port d lcd
#define DS1820_PIN PIN_A2
#define use_portd_lcd TRUE
#include "lcd.c"
void main() {
float minstep;
int16 a;
int b;
lcd_init();
do {
minstep = read_full_temp();
printf (lcd_putc,"\fTemp :%3.2f C", minstep);
delay_ms(1000);
} while (TRUE);
}