![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/08\/data-logger-circuit.jpg?resize=700%2C516&quality=100&strip=all&ssl=1\")
<\/p>\nThis post shows you how to create a temperature Arduino data logger. We\u2019ll use the DHT11 to measure temperature, the real time clock (RTC) module to take time stamps and the SD card module to save the data on the SD card.<\/p>\n
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Recommended resources:<\/strong><\/p>\n Here\u2019s a complete list of the parts required for this project:<\/p>\n Note: alternatively to the SD card module, you can use a data logging shield<\/a>. The data logging shield comes with built-in RTC and a prototyping area for soldering connections, sensors, etc..<\/p>\n You can use the preceding links or go directly to MakerAdvisor.com\/tools<\/a> to find all the parts for your projects at the best price!<\/p> The following figure shows the circuit\u2019s schematics for this project.<\/p>\n Note:<\/strong> make sure your SD card is formatted and working properly. Read “Guide to SD card module with Arduino<\/a>“.<\/p>\n For this project you need to install the DHT library to read from the DHT11 sensor.<\/p>\n Copy the following code to your Arduino IDE and upload it to your Arduino board.<\/p>\n View raw code<\/a><\/p>\n In this code we create a loggingTime()<\/strong> function and a loggingTemperature()<\/strong> function that we call in the loop()<\/strong> to log the time and temperature to the DATA.txt<\/strong> file in the SD card.<\/p>\n Open the Serial Monitor at a baud rate of 9600 and check if everything is working properly.<\/p>\n Let this project run for a few hours to gather a decent amount of data, and when you\u2019re happy with the data logging period, shut down the Arduino and remove the SD from the SD card module.<\/p>\n Insert the SD card on your computer, open it, and you should have a DATA.txt<\/strong> file with the collected data.<\/p>\n You can open the data with a text editor, or use a spreadsheet to analyse and process your data.<\/p>\n The data is separated by commas, and each reading is in a new line. In this format, you can easily import data to Excel or other data processing software.<\/p>\n This is a great project to learn how to use the SD card module with Arduino to build a data logger. You can apply this concept in pretty much any project you’d like.<\/p>\n If you like Arduino projects, make sure you check our latest Arduino course:\u00a0Arduino Step-by-step Projects \u2013 Build 23 Projects<\/a><\/strong><\/p>\n We hope you\u2019ve found this project useful.<\/p>\n Thanks for reading.<\/p>\n","protected":false},"excerpt":{"rendered":" This post shows you how to create a temperature Arduino data logger. We\u2019ll use the DHT11 to measure temperature, the real time clock (RTC) module to take time stamps and … <\/p>\n\n
Parts required<\/h2>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/08\/data-logger-parts.jpg?resize=700%2C518&quality=100&strip=all&ssl=1\")
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![](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/10\/header-200.png?w=1200&quality=100&strip=all&ssl=1\")
<\/a><\/p>\nSchematics<\/h2>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/08\/temperature-datalogger_bb.png?resize=1200%2C533&quality=100&strip=all&ssl=1\")
<\/a><\/p>\nInstalling the DHT sensor library<\/h4>\n
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DHT-sensor-library-master<\/del> to DHT <\/strong><\/li>\nCode<\/h2>\n
\/*\n * Rui Santos \n * Complete Project Details http:\/\/randomnerdtutorials.com\n *\/\n\n#include <SPI.h> \/\/for the SD card module\n#include <SD.h> \/\/ for the SD card\n#include <DHT.h> \/\/ for the DHT sensor\n#include <RTClib.h> \/\/ for the RTC\n\n\/\/define DHT pin\n#define DHTPIN 2 \/\/ what pin we're connected to\n\n\/\/ uncomment whatever type you're using\n#define DHTTYPE DHT11 \/\/ DHT 11 \n\/\/#define DHTTYPE DHT22 \/\/ DHT 22 (AM2302)\n\/\/#define DHTTYPE DHT21 \/\/ DHT 21 (AM2301)\n\n\/\/ initialize DHT sensor for normal 16mhz Arduino\nDHT dht(DHTPIN, DHTTYPE);\n\n\/\/ change this to match your SD shield or module;\n\/\/ Arduino Ethernet shield and modules: pin 4\n\/\/ Data loggin SD shields and modules: pin 10\n\/\/ Sparkfun SD shield: pin 8\nconst int chipSelect = 4; \n\n\/\/ Create a file to store the data\nFile myFile;\n\n\/\/ RTC\nRTC_DS1307 rtc;\n\nvoid setup() {\n \/\/initializing the DHT sensor\n dht.begin();\n\n \/\/initializing Serial monitor\n Serial.begin(9600);\n \n \/\/ setup for the RTC\n while(!Serial); \/\/ for Leonardo\/Micro\/Zero\n if(! rtc.begin()) {\n Serial.println("Couldn't find RTC");\n while (1);\n }\n else {\n \/\/ following line sets the RTC to the date & time this sketch was compiled\n rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));\n }\n if(! rtc.isrunning()) {\n Serial.println("RTC is NOT running!");\n }\n \n \/\/ setup for the SD card\n Serial.print("Initializing SD card...");\n\n if(!SD.begin(chipSelect)) {\n Serial.println("initialization failed!");\n return;\n }\n Serial.println("initialization done.");\n \n \/\/open file\n myFile=SD.open("DATA.txt", FILE_WRITE);\n\n \/\/ if the file opened ok, write to it:\n if (myFile) {\n Serial.println("File opened ok");\n \/\/ print the headings for our data\n myFile.println("Date,Time,Temperature \u00baC");\n }\n myFile.close();\n}\n\nvoid loggingTime() {\n DateTime now = rtc.now();\n myFile = SD.open("DATA.txt", FILE_WRITE);\n if (myFile) {\n myFile.print(now.year(), DEC);\n myFile.print('\/');\n myFile.print(now.month(), DEC);\n myFile.print('\/');\n myFile.print(now.day(), DEC);\n myFile.print(',');\n myFile.print(now.hour(), DEC);\n myFile.print(':');\n myFile.print(now.minute(), DEC);\n myFile.print(':');\n myFile.print(now.second(), DEC);\n myFile.print(",");\n }\n Serial.print(now.year(), DEC);\n Serial.print('\/');\n Serial.print(now.month(), DEC);\n Serial.print('\/');\n Serial.println(now.day(), DEC);\n Serial.print(now.hour(), DEC);\n Serial.print(':');\n Serial.print(now.minute(), DEC);\n Serial.print(':');\n Serial.println(now.second(), DEC);\n myFile.close();\n delay(1000); \n}\n\nvoid loggingTemperature() {\n \/\/ Reading temperature or humidity takes about 250 milliseconds!\n \/\/ Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)\n \/\/ Read temperature as Celsius\n float t = dht.readTemperature();\n \/\/ Read temperature as Fahrenheit\n \/\/float f = dht.readTemperature(true);\n \n \/\/ Check if any reads failed and exit early (to try again).\n if (isnan(t) \/*|| isnan(f)*\/) {\n Serial.println("Failed to read from DHT sensor!");\n return;\n }\n \n \/\/debugging purposes\n Serial.print("Temperature: "); \n Serial.print(t);\n Serial.println(" *C");\n \/\/Serial.print(f);\n \/\/Serial.println(" *F\\t"); \n \n myFile = SD.open("DATA.txt", FILE_WRITE);\n if (myFile) {\n Serial.println("open with success");\n myFile.print(t);\n myFile.println(",");\n }\n myFile.close();\n}\n\nvoid loop() {\n loggingTime();\n loggingTemperature();\n delay(5000);\n}\n<\/code><\/pre>\n\tGetting the data from the SD card<\/h2>\n
![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/08\/datafile.png?resize=82%2C120&quality=100&strip=all&ssl=1\")
<\/p>\n![\"\"](\"https:\/\/i0.wp.com\/randomnerdtutorials.com\/wp-content\/uploads\/2017\/08\/data-txt.png?resize=493%2C542&quality=100&strip=all&ssl=1\")
<\/p>\nWrapping up<\/h2>\n