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Код: Выделить всё • Развернуть

#include <OneWire.h>
#include <Wire.h> 

OneWire  ds(10);  // on pin 10

void setup(void) {
  Serial.begin(9600);
  ds.reset();

}

unsigned int readBytes(int count)
{
    unsigned int val = 0;
    for (int i = 0; i < count; i++)
    {
        val |= (unsigned int)(ds.read() << i * 8);
    }
    return val;
}

void loop(void) {
  byte temp_read = 0;
  unsigned int count_remain = 0;
  unsigned int count_per_c = 0;
  byte configuration_register = 0;

  ds.reset();
  ds.write(0xEE); //Start Converting the temperatures  
  
   do {
        delay(1);
        configuration_register = 0;
        ds.reset();
        ds.write(0xAC);

        // Read the configuration Register from the DS1821
        configuration_register = readBytes(1);
    } while ((configuration_register & (1 << 7)) == 0); // If Bit #8 is 1 then we are finished converting the temp

  
    // Get Temp
    ds.reset();
    ds.write(0xAA);
    temp_read = readBytes(1); ;

    // Get Count Remaining
    ds.reset();
    ds.write(0xA0);
    count_remain = readBytes(2);

    // Load The Counter to populate the slope accumulator
    ds.reset();
    ds.write(0x41);

    // Read Count Per Deg
    ds.reset();
    ds.write(0xA0);
    count_per_c = readBytes(2);

    // If we are reading above the 200 mark then we are below 0 and need to compensate the calculation
    if (temp_read >= 200) temp_read -= 256;

    float highResTemp = (float)temp_read - .5 + (((float)count_per_c - (float)count_remain) / (float)count_per_c);

    highResTemp = (float)((1.80 * highResTemp) + 32.00);
    Serial.print(highResTemp);
    Serial.println(" Fahrenheit");

   delay(1000);
}

Код: Выделить всё • Развернуть

configuration_register = readBytes(1);

There is an Arduino project for this called OneWire but I had trouble getting it going and it was late so I wrote my own code. (Also, this is the sort of thing I love).

HIGH-RESOLUTION TEMPERATURE READINGS
The user can calculate temperature values with higher than 8-bit resolution using the data remaining in
the counter and slope accumulator when the temperature conversion is complete. To do this the user must
first read the temperature from the 8-bit temperature register. This value is called TEMP_READ in the
high-resolution equation (see Eq. 1). The 9-bit counter value must then be obtained by issuing the Read
Counter [A0h] command. This value is the count remaining in the counter at the end of the gate period
and is called COUNT_REMAIN in Eq. 1. Next the Load Counter [41h] command must be issued, which
loads the 9-bit slope accumulator value into the counter register. The slope accumulator value (called
COUNT_PER_C in Eq. 1) can then be read from the counter by again issuing the Read Counter [A0h]
command. The slope accumulator value is called “COUNT_PER_C” because it represents the number of
counts needed for an accurate measurement at a given temperature (i.e., the counts per degree C). The
high-resolution temperature can then be calculated using Eq. 1:
Eq. 1) "формула"
High-resolution temperature readings cannot be used while in continuous conversion mode. Also, the
Read Counter [A0h] and Load Counter [41h] commands must not be used while in continuous conversion
mod

Код: Выделить всё • Развернуть

 void wait(void)
{char x;
 w1_init();                           // инициализация датчика
 w1_write(0xEE);                      // WRITE COMMAND START CONVERT EEh
 do
 {
 w1_init();                           // инициализация датчика
 w1_write(0xAC);                      // WRITE COMMAND READ STATUS ACh
 x=w1_read();
 }
 while(!(0b10000000&x));      // READ STATUS
}

void main(void)
{
// Declare your local variables here

init_tiny2313(); // инициализация МК

// Global enable interrupts
#asm("sei")

lcd_init(16);

{
lcd_clear();
lcd_gotoxy(0,0);
}

while (1)
{
 // Place your code here
 wait();                              // ждем готовности
 w1_init();                           // инициализация датчика
 w1_write(0xAA);                      // WRITE COMMAND READ TEMPERATURE 0AAh
 TEMP_READ=w1_read();                 // READ

 w1_init();                           // инициализация датчика
 w1_write(0xA0);                      // WRITE COMMAND READ COUNTER A0h
 COUNT_REMAIN=w1_read();              // READ

 w1_init();                           // инициализация датчика
 w1_write(0x41);                      // WRITE COMMAND LOAD COUNTER 41h
 w1_write(0xA0);                      // WRITE COMMAND READ COUNTER A0h
 COUNT_PER_C=w1_read();               // READ

if (!COUNT_PER_C) COUNT_PER_C++;

 temp_x_100=((short int)TEMP_READ)*100-50+100*(COUNT_PER_C-COUNT_REMAIN)/COUNT_PER_C;

 //temp_x_100=2740; // для отладки отображения температуры
 //if (temp_x_100>TEMPERATURA_MAX)TEMPERATURA_MAX=temp_x_100;
// if (temp_x_100<TEMPERATURA_MIN)TEMPERATURA_MIN=temp_x_100;
// if (time_count>400*20) out_min_max();
//    else
    out_displei();



};// END While

}// END MAIN

Код: Выделить всё • Развернуть

#include <tiny2313.h>
#include <1wire.h>
#include <delay.h>
#include <Hardware.h>
#include <7seg.h>

Код: Выделить всё • Развернуть

 temp_read-27.00 status_read-11010001 highResTemp - 27.10
 temp_read-27.00 status_read-11010001 highResTemp - 27.10
 temp_read-27.00 status_read-11010001 highResTemp - 27.09
 temp_read-27.00 status_read-11010001 highResTemp - 27.07
 temp_read-27.00 status_read-11010001 highResTemp - 27.05  
 temp_read-26.00 status_read-11010001 highResTemp - 26.49 вот тут перещёлкнулось с 27 на 26 и дробная часть стала уменьшаться.
 temp_read-26.00 status_read-11010001 highResTemp - 26.43
 temp_read-26.00 status_read-11010001 highResTemp - 26.39
 temp_read-26.00 status_read-11010001 highResTemp - 26.34

Код: Выделить всё • Развернуть

float highResTemp = (float)temp_read - 0.5 + (((float)count_per_c - (float)count_remain) / (float)count_per_c);

Myp писал(а):тока странно
целая часть правильная, а вот дробная часть от .00 до .50, на .50 перещёлкивается целая часть.