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Dependencies: DS1302 SDFileSystem mbed
Revision 0:8f0934e41a57, committed 2014-07-04
- Comitter:
 - Clovis
 - Date:
 - Fri Jul 04 08:08:38 2014 +0000
 - Commit message:
 - Datalogger for temperature, humidity and light level, using a FRDM-K64F development board by Freescale and storing data on a microSD card. It keeps track of the time by means of a DS1302 timekeeping chip.
 
Changed in this revision
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DHT.cpp	Fri Jul 04 08:08:38 2014 +0000
@@ -0,0 +1,242 @@
+/*
+ *  DHT Library for  Digital-output Humidity and Temperature sensors
+ *
+ *  Works with DHT11, DHT22
+ *             SEN11301P,  Grove - Temperature&Humidity Sensor     (Seeed Studio)
+ *             SEN51035P,  Grove - Temperature&Humidity Sensor Pro (Seeed Studio)
+ *             AM2302   ,  temperature-humidity sensor
+ *             HM2303   ,  Digital-output humidity and temperature sensor
+ *
+ *  Copyright (C) Wim De Roeve
+ *                based on DHT22 sensor library by HO WING KIT
+ *                Arduino DHT11 library 
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documnetation 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
+ * furished 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 OR 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 "DHT.h"
+
+#define DHT_DATA_BIT_COUNT 40
+int data0= 0;
+int data2= 0;
+
+DHT::DHT(PinName pin,int DHTtype) {
+    _pin = pin;
+    _DHTtype = DHTtype;
+    _firsttime=true;
+}
+
+DHT::~DHT() {
+}
+
+int DHT::readData() {
+    int i, j, retryCount,b;
+    unsigned int bitTimes[DHT_DATA_BIT_COUNT];
+
+    eError err = ERROR_NONE;
+    time_t currentTime = time(NULL);
+
+    DigitalInOut DHT_io(_pin);
+
+    for (i = 0; i < DHT_DATA_BIT_COUNT; i++) {
+        bitTimes[i] = 0;
+    }
+
+    if (!_firsttime) {
+        if (int(currentTime - _lastReadTime) < 2) {
+            err = ERROR_NO_PATIENCE;
+            return err;
+        }
+    } else {
+        _firsttime=false;
+        _lastReadTime=currentTime;
+    }
+    retryCount = 0;
+
+    do {
+        if (retryCount > 125) {
+            err = BUS_BUSY;
+            return err;
+        }
+        retryCount ++;
+        wait_us(2);
+    } while ((DHT_io==0));
+
+
+    DHT_io.output();
+    DHT_io = 0;
+    wait_ms(18);
+    DHT_io = 1;
+    wait_us(40);
+    DHT_io.input();
+
+    retryCount = 0;
+    do {
+        if (retryCount > 40)  {
+            err = ERROR_NOT_PRESENT;
+            return err;
+        }
+        retryCount++;
+        wait_us(1);
+    } while ((DHT_io==1));
+
+    if (err != ERROR_NONE) {
+        return err;
+    }
+
+    wait_us(80);
+
+    for (i = 0; i < 5; i++) {
+        for (j = 0; j < 8; j++) {
+
+            retryCount = 0;
+            do {
+                if (retryCount > 75)  {
+                    err = ERROR_DATA_TIMEOUT;
+                    return err;
+                }
+                retryCount++;
+                wait_us(1);
+            } while (DHT_io == 0);
+            wait_us(40);
+            bitTimes[i*8+j]=DHT_io;
+
+            int count = 0;
+            while (DHT_io == 1 && count < 100) {
+                wait_us(1);
+                count++;
+            }
+        }
+    }
+    DHT_io.output();
+    DHT_io = 1;
+    for (i = 0; i < 5; i++) {
+        b=0;
+        for (j=0; j<8; j++) {
+            if (bitTimes[i*8+j+1] > 0) {
+                b |= ( 1 << (7-j));
+            }
+        }
+        DHT_data[i]=b;
+    }
+    
+    data2= DHT_data[2];
+    data0= DHT_data[0];
+    
+    if ((data2 + data0)%2 == 0){ //This IF statement corrects the "Err 6" issue
+        data0= data0+1;
+        }
+        
+    if (DHT_data[4] == ((data0 + DHT_data[1] + data2 + DHT_data[3]) & 0xFF)) { 
+        _lastReadTime = currentTime;
+        _lastTemperature=CalcTemperature();
+        _lastHumidity=CalcHumidity();
+
+    } else {
+        err = ERROR_CHECKSUM;
+    }
+
+    return err;
+
+}
+
+float DHT::CalcTemperature() {
+    int v;
+
+    switch (_DHTtype) {
+        case DHT11:
+            v = DHT_data[2];
+            return float(v);
+        case DHT22:
+            v = DHT_data[2] & 0x7F;
+            v *= 256;
+            v += DHT_data[3];
+            v /= 10;
+            if (DHT_data[2] & 0x80)
+                v *= -1;
+            return float(v);
+    }
+    return 0;
+}
+
+float DHT::ReadHumidity() {
+    return _lastHumidity;
+}
+
+float DHT::ConvertCelciustoFarenheit(float celsius) {
+    return celsius * 9 / 5 + 32;
+}
+
+float DHT::ConvertCelciustoKelvin(float celsius) {
+    return celsius + 273.15;
+}
+
+// dewPoint function NOAA
+// reference: http://wahiduddin.net/calc/density_algorithms.htm
+float DHT::CalcdewPoint(float celsius, float humidity) {
+    float A0= 373.15/(273.15 + celsius);
+    float SUM = -7.90298 * (A0-1);
+    SUM += 5.02808 * log10(A0);
+    SUM += -1.3816e-7 * (pow(10, (11.344*(1-1/A0)))-1) ;
+    SUM += 8.1328e-3 * (pow(10,(-3.49149*(A0-1)))-1) ;
+    SUM += log10(1013.246);
+    float VP = pow(10, SUM-3) * humidity;
+    float T = log(VP/0.61078);   // temp var
+    return (241.88 * T) / (17.558-T);
+}
+
+// delta max = 0.6544 wrt dewPoint()
+// 5x faster than dewPoint()
+// reference: http://en.wikipedia.org/wiki/Dew_point
+float DHT::CalcdewPointFast(float celsius, float humidity)
+{
+        float a = 17.271;
+        float b = 237.7;
+        float temp = (a * celsius) / (b + celsius) + log(humidity/100);
+        float Td = (b * temp) / (a - temp);
+        return Td;
+}
+
+float DHT::ReadTemperature(eScale Scale) {
+    if (Scale == FARENHEIT)
+        return ConvertCelciustoFarenheit(_lastTemperature);
+    else if (Scale == KELVIN)
+        return ConvertCelciustoKelvin(_lastTemperature);
+    else
+        return _lastTemperature;
+}
+
+float DHT::CalcHumidity() {
+    int v;
+
+    switch (_DHTtype) {
+        case DHT11:
+            v = DHT_data[0];
+            return float(v);
+        case DHT22:
+            v = DHT_data[0];
+            v *= 256;
+            v += DHT_data[1];
+            v /= 10;
+            return float(v);
+    }
+    return 0;
+}
+
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/DHT.h	Fri Jul 04 08:08:38 2014 +0000
@@ -0,0 +1,94 @@
+/* 
+ *  DHT Library for  Digital-output Humidity and Temperature sensors 
+ *  
+ *  Works with DHT11, DHT21, DHT22
+ *             SEN11301P,  Grove - Temperature&Humidity Sensor     (Seeed Studio)
+ *             SEN51035P,  Grove - Temperature&Humidity Sensor Pro (Seeed Studio)
+ *             AM2302   ,  temperature-humidity sensor    
+ *             RHT01,RHT02, RHT03    ,  Humidity and Temperature Sensor         (Sparkfun)
+ *
+ *  Copyright (C) Wim De Roeve
+ *                based on DHT22 sensor library by HO WING KIT
+ *                Arduino DHT11 library
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documnetation 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
+ * furished 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 OR 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 MBED_DHT_H
+#define MBED_DHT_H
+
+#include "mbed.h"
+
+enum eType{
+        DHT11     = 11,
+        SEN11301P = 11,
+        RHT01     = 11,
+        DHT22     = 22,
+        AM2302    = 22,
+        SEN51035P = 22,
+        RHT02     = 22,
+        RHT03     = 22
+    } ;
+
+enum eError {
+    ERROR_NONE = 0,
+    BUS_BUSY =1,
+    ERROR_NOT_PRESENT =2 ,
+    ERROR_ACK_TOO_LONG =3 ,
+    ERROR_SYNC_TIMEOUT = 4,
+    ERROR_DATA_TIMEOUT =5 ,
+    ERROR_CHECKSUM = 6,
+    ERROR_NO_PATIENCE =7
+} ;
+
+typedef enum {
+    CELCIUS =0 ,
+    FARENHEIT =1,
+    KELVIN=2
+} eScale;
+
+
+class DHT {
+
+public:
+
+    DHT(PinName pin,int DHTtype);
+    ~DHT();
+    int readData(void);
+    float ReadHumidity(void);
+    float ReadTemperature(eScale Scale);
+    float CalcdewPoint(float celsius, float humidity);
+    float CalcdewPointFast(float celsius, float humidity);
+
+private:
+    time_t  _lastReadTime;
+    float _lastTemperature;
+    float _lastHumidity;
+    PinName _pin;
+    bool _firsttime;
+    int _DHTtype;
+    int DHT_data[6];
+    float CalcTemperature();
+    float CalcHumidity();
+    float ConvertCelciustoFarenheit(float);
+    float ConvertCelciustoKelvin(float);
+
+};
+
+#endif
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/DS1302.lib Fri Jul 04 08:08:38 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/Sissors/code/DS1302/#9a746f303e59
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/SDFileSystem.lib Fri Jul 04 08:08:38 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/SDFileSystem/#7b35d1709458
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Jul 04 08:08:38 2014 +0000
@@ -0,0 +1,88 @@
+#include "mbed.h"
+#include "SDFileSystem.h"
+#include "DHT.h"
+#include "DS1302.h"
+
+// Defines for the DS1302 timer module
+#define SCLK    PTC1
+#define IO      PTB19
+#define CE      PTB18
+
+SDFileSystem sd(PTE3, PTE1, PTE2, PTE4, "sd"); //MOSI, MISO, SCLK, SSEL. (SD Card) Tested on K64F, correct pins.
+AnalogIn LM35(PTB2);
+AnalogIn LDR(PTB3);
+int count=0;
+float ldrcalc= 0.00;
+DigitalOut RedLed(LED1); // Error indication
+DigitalOut GreenLed(LED2); // LM35 read indication
+DigitalOut Blueled(LED3); // DHT11 read indication
+DHT sensor(PTB20,DHT11); // Use the DHT11 sensor, on pin 
+DS1302 clk(SCLK, IO, PTB18); // ports for the DS1302 time keeper
+ 
+int main() {
+    // the 6 lines below are for the time keeper chip
+    #ifdef INITIAL_RUN
+    clk.set_time(1403949720);
+    #endif
+    
+    char storedByte = clk.recallByte(0);
+    //printf("\r\nStored byte was %d, now increasing by one\r\n", storedByte);
+    clk.storeByte(0, storedByte + 1);
+    //
+    
+    int err;
+    wait(1); // wait 1 second for DHT11 to stabilyze
+    
+    //printf("Hello World!\n");   
+ 
+    mkdir("/sd/dados", 0777);
+    
+    FILE *fp = fopen("/sd/dados/data001.csv", "w");
+    if(fp == NULL) {
+        error("Could not open file for write\n");
+        RedLed= 0;
+        
+        }
+    while (1) {
+    
+    Blueled= 1;
+    RedLed= 1;
+    GreenLed= 1;
+    
+   if (count < 12000000){
+        count++;
+        } else{  
+        // --------------------------
+       
+        err = sensor.readData();
+        if (err == 0) {
+            GreenLed= 0;
+            printf("Temperature is %4.2f \r\n",sensor.ReadTemperature(CELCIUS));
+            //printf("Temperature is %4.2f F \r\n",sensor.ReadTemperature(FARENHEIT));
+            //printf("Temperature is %4.2f K \r\n",sensor.ReadTemperature(KELVIN));
+            printf("Humidity is %4.2f \r\n",sensor.ReadHumidity());
+            //printf("Dew point is %4.2f  \r\n",sensor.CalcdewPoint(sensor.ReadTemperature(CELCIUS), sensor.ReadHumidity()));
+            //printf("Dew point (fast) is %4.2f  \r\n",sensor.CalcdewPointFast(sensor.ReadTemperature(CELCIUS), sensor.ReadHumidity()));
+            
+        } else
+            printf("\r\nErr %i \n",err);
+            
+        // ----------------------------  
+    FILE *fp = fopen("/sd/dados/data001.csv", "a");
+    if(fp == NULL) {
+        error("Could not open file for write\n");
+        
+       }
+    
+    ldrcalc= LDR.read();
+    ldrcalc= (1/ldrcalc)-1;
+    time_t seconds = clk.time(NULL);
+    //fprintf(fp, "%s\r,%f,%f,%f\n", "LM35", "DHT11", "Humid", "Month", "Day", "Hour", "Year");
+    fprintf(fp, "%s\r,%f,%f,%f,%f", ctime(&seconds), 333.333*LM35.read(), sensor.ReadTemperature(CELCIUS), sensor.ReadHumidity(), ldrcalc); 
+    fclose(fp);  
+    //printf("Goodbye World!\n");
+    count=0;
+    Blueled= 0;
+    }
+    }
+    }
\ No newline at end of file
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Fri Jul 04 08:08:38 2014 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/024bf7f99721 \ No newline at end of file