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Find out all the best information, libraries and circuit about the latest Embedded systems.
Showing posts with label temperature. Show all posts
Showing posts with label temperature. Show all posts

Sunday, 6 January 2013

Arduino code for MAX6675

.from: https://github.com/codebendercc/arduino-files/blob/master/extra-libraries/max6675/max6675.cpp

X================================X max6675.h X================================X

// this library is public domain. enjoy!
// www.ladyada.net/learn/sensors/thermocouple

#if ARDUINO >= 100
 #include "Arduino.h"
#else
 #include "WProgram.h"
#endif

class MAX6675 {
 public:
  MAX6675(int8_t SCLK, int8_t CS, int8_t MISO);

  double readCelsius(void);
  double readFahrenheit(void);
  // For compatibility with older versions:
  double readFarenheit(void) { return readFahrenheit(); }
 private:
  int8_t sclk, miso, cs;
  uint8_t spiread(void);
};

X================================X max6675.cpp X================================X

// this library is public domain. enjoy!
// www.ladyada.net/learn/sensors/thermocouple

#include <avr pgmspace.h="pgmspace.h">
#include <util delay.h="delay.h">
#include <stdlib .h=".h">
#include "max6675.h"

MAX6675::MAX6675(int8_t SCLK, int8_t CS, int8_t MISO) {
  sclk = SCLK;
  cs = CS;
  miso = MISO;

  //define pin modes
  pinMode(cs, OUTPUT);
  pinMode(sclk, OUTPUT);
  pinMode(miso, INPUT);

  digitalWrite(cs, HIGH);
}
double MAX6675::readCelsius(void) {

  uint16_t v;

  digitalWrite(cs, LOW);
  _delay_ms(1);

  v = spiread();
  v &lt;&lt;= 8;
  v |= spiread();

  digitalWrite(cs, HIGH);

  if (v &amp; 0x4) {
    // uh oh, no thermocouple attached!
    return NAN;
    //return -100;
  }

  v &gt;&gt;= 3;

  return v*0.25;
}

double MAX6675::readFahrenheit(void) {
  return readCelsius() * 9.0/5.0 + 32;
}

byte MAX6675::spiread(void) {
  int i;
  byte d = 0;

  for (i=7; i&gt;=0; i--)
  {
    digitalWrite(sclk, LOW);
    _delay_ms(1);
    if (digitalRead(miso)) {
      //set the bit to 0 no matter what
      d |= (1 &lt;&lt; i);
    }

    digitalWrite(sclk, HIGH);
    _delay_ms(1);
  }

  return d;
}

X================================X X================================X


</stdlib></util></avr>

Sunday, 8 January 2012

MBED: Read TMP102 Temperature Sensor using I2C (Cookbook)

.from: http://mbed.org/users/donatien/programs/TMP102/5z9h3

The TMP102 is another I2C digital temperature sensor in a small SOT563 package
/media/uploads/chris/tmp102_crop.jpg
TMP102mbed
1 - Vcc (square pad)Vout
2 - SDAp9
3 - SCLp10
4 - GndGnd

XxXxXxXxXxXxXxXxXxXxXxXxXxXx TMP102.cpp XxXxXxXxXxXxXxXxXxXxXxXxXxXx


/*
Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#include "TMP102.h"

#define TEMP_REG_ADDR 0x00

TMP102::TMP102(PinName sda, PinName scl, int addr) : m_i2c(sda, scl), m_addr(addr)
{

}

TMP102::~TMP102()
{

}

float TMP102::read()
{
  I2C temperatureIn(p9, p10);
 
  const char tempRegAddr = TEMP_REG_ADDR;

  m_i2c.write(m_addr, &tempRegAddr, 1); //Pointer to the temperature register

  char reg[2] = {0,0};
  m_i2c.read(m_addr, reg, 2); //Rea
 
  unsigned short res = (reg[0] << 4) | (reg[1] >> 4);
 
  float temp =  (float) ((float)res * 0.0625);
  
  return temp;
}

XxXxXxXxXxXxXxXxXxXxXxXxXxXx TMP102.h XxXxXxXxXxXxXxXxXxXxXxXxXxXx


/*
Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com)

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

#ifndef TMP102_H
#define TMP102_H

#include "mbed.h"

//!Library for the TI TMP102 temperature sensor.
/*!
The TMP102 is an I2C digital temperature sensor in a small SOT563 package, with a 0.0625C resolution and 0.5C accuracy.
*/
class TMP102
{
public:
  //!Creates an instance of the class.
  /*!
  Connect module at I2C address addr using I2C port pins sda and scl.
  TMP102
  \param addr <table><tr><th>A0 pin connection</th><th>Address</th></tr><tr><td>GND</td><td>0x90</td></tr><tr><td>V+</td><td>0x92</td></tr><tr><td>SDA</td><td>0x94</td></tr><tr><td>SCL</td><td>0x96</td></tr></table> 
  */
  TMP102(PinName sda, PinName scl, int addr);
 
  /*!
  Destroys instance.
  */
  ~TMP102();
 
  //!Reads the current temperature.
  /*!
  Reads the temperature register of the TMP102 and converts it to a useable value.
  */
  float read();
 
private:
  I2C m_i2c;
  int m_addr;

};

#endif

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Saturday, 7 January 2012

MBED Example: How to use DS1620 Temperature Monitor

.from: http://www.frank-zhao.com/thingspeak_mbed_tut1/

#include "mbed.h"
#include "EthernetNetIf.h"
#include "NTPClient.h"
#include "HTTPClient.h"


// networking stuff
EthernetNetIf eth;
NTPClient ntp;
HTTPClient http;

char* ntpServerUrl = "0.ca.pool.ntp.org";

char* thingSpeakUrl = "http://api.thingspeak.com/update";
char* thingSpeakKey = "IS6YCLKIR423VO5H";

char urlBuffer[256];
char timeBuffer[64];

// pin defs
DigitalOut rst(p30);
DigitalOut clk(p29);
DigitalInOut dq(p28);

void DS1620Send(long data, int numOfBits)
{
    dq.output(); // we are sending
   
    for (int i = 0; i < numOfBits; i++)
    {
        clk = 0;
        wait_us(0.05);
        if (data & (1 << i)) // bit is 1
        {
            dq = 1;
        }
        else // bit is 0
        {
            dq = 0;
        }
        wait_us(0.5);
        clk = 1;
        wait_us(0.5);
    }
   
    dq.input(); // go back to being input
   
    clk = 1; // leave high
}

float DS1620ReadTemp()
{
    rst = 1;
    DS1620Send(0xAA, 8); // read temp command
   
    dq.input();
    int results = 0;
   
    // read in 9 bits
    for (int i = 0; i < 9; i++)
    {
        clk = 0;
        wait_us(0.5);
        clk = 1;
        wait_us(0.05);
        if (dq.read() != 0) // bit is 1
        {
            if (i < 8)
            {
                results |= 1 << i;
            }
            else
            {
                results *= -1; // last bit is sign bit
            }
        }
        wait_us(0.4);
    }
   
    clk = 1; // leave high
   
    rst = 0;
   
    return (float)results / 2; // div by 2 since last bit is 0.5
}

void DS1620Setup()
{
    // initial pin states
    rst = 0;
    clk = 1;
    dq.input();
    wait(0.1);
   
    rst = 1;
    DS1620Send(0x0A0C, 16); // config for continuous mode with CPU mode
    rst = 0;
    wait(0.1);
    rst = 1;
    DS1620Send(0xEE, 8); // start continuous conversions
    rst = 0;
    wait(0.1);
}

int main() {

    printf("Start\r\n");

    printf("Setting up Ethernet...\r\n");
    EthernetErr ethErr = eth.setup();
    if(ethErr)
    {
        printf("Error %d in ethernet setup.\r\n", ethErr);
        return -1;
    }
    printf("Ethernet setup OK\r\n");
   
    // get time from ntp
    time_t ctTime;
    Host server(IpAddr(), 123, ntpServerUrl);
    ntp.setTime(server);
   
    // start the sensor
    DS1620Setup();
   
    while(1)
    {
        // update data here
        ctTime = time(NULL);
        float temperature = DS1620ReadTemp();
       
        // format time here
        timeBuffer[0] = 0;
        strftime(timeBuffer, 64, "%Y-%m-%d %H:%M:%S", localtime(&ctTime));
       
        // for debug
        printf("Time: %s, Temperature: %f\r\n", timeBuffer, temperature);
       
        // format url here
        urlBuffer[0] = 0;
        sprintf(urlBuffer, "%s?key=%s&field1=%s&field2=%f", thingSpeakUrl, thingSpeakKey, timeBuffer, temperature);
        printf("Request to %s\r\n", urlBuffer);
       
        HTTPText resp;
        HTTPResult res = http.get(urlBuffer, &resp);
        if (res == HTTP_OK)
        {
            printf("Result :\"%s\"\r\n", resp.gets());
        }
        else
        {
            printf("Error %d\r\n", res);
        }
       
        wait(16); // limited by ThingSpeak's API
    }
   
    return 0;
   
}

MBED Example: How to use analog input pin (ADC, AnalogIn)

.from: http://mbed.org/projects/libraries/svn/mbed/trunk/AnalogIn.h

// Print messages when the AnalogIn is greater than 50%

#include "mbed.h"

AnalogIn temperature(p20);

int main() {
 while(1) {
     if(temperature > 0.5) {
         printf("Too hot! (%f)", temperature.read());            
     }
 }
}