Clovis Fritzen
Datalogger that reads temperature, humidity and light level every 10 seconds, and store the data in a microSD card (.CSV file).
Dependencies: DS1302 SDFileSystem mbed
This is a weather station/datalogger using a Freescale FRDM-K64F dev board, a LM35 (temperature sensor), a DHT11 (temperature and humidity sensor), a DS1302 (timekeeper module) and a LDR (light level sensor). All the data is periodically stored on a microSDHC card; The acquisition period is adjustable via software (by setting the value of a counter).
There is also (commented) code for sending all these information via serial to a terminal on PC.
Full explanation, details and schematics can be found here: http://embedded-clovis.blogspot.ca/2014/07/temperature-datalogger-with-arm-cortex.html
Diff: main.cpp
- Revision:
- 0:8f0934e41a57
--- /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;
+ }
+ }
+ }
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