NodeMCU ESP8266 / ESP8285 Arduino #36 ESP8266 NodeMCU DHT11/DHT22 Data Logger : บันทึกข้อมูล อุณหภูมิความชื้นพร้อมเวลาด้วย SD Card และ NodeMCU

/*
SD Card
CS – D8
SCK – D5
MOSI – D7
MISO – D6
VCC – 3.3V
GND – GND
==========
DHT
1 - 3.3V
2 - D2
4 - GND
R 4.7K ต่อคร่อมขา 1 และ 2
*/
#include 
#include 
#include 
#include 
#include 

#define DHTPIN D2
#define DHTTYPE DHT11 // DHT 11
//#define DHTTYPE DHT22 // DHT 22 (AM2302), AM2321
//#define DHTTYPE DHT21 // DHT 21 (AM2301)

const char* ssid = "wifi_ssid"; //ใส่ชื่อ SSID Wifi
const char* password = "wifi_password"; //ใส่รหัสผ่าน

int timezone = 7 * 3600; //ตั้งค่า TimeZone ตามเวลาประเทศไทย
int dst = 0; //กำหนดค่า Date Swing Time


DHT dht(DHTPIN, DHTTYPE);
const int chipSelect = 4;

void setup() {
// Open serial communications and wait for port to open:
Serial.begin(115200);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}


Serial.print("Initializing SD card...");

if (!SD.begin(chipSelect)) {
Serial.println("Card failed, or not present");
}
Serial.println("SD Card OK");
dht.begin();

WiFi.mode(WIFI_STA); //เชื่อมต่อ Wifi
WiFi.begin(ssid, password);
Serial.println("\nConnecting to WiFi");
while (WiFi.status() != WL_CONNECTED) {
Serial.print("*");
delay(1000);
}
configTime(timezone, dst, "pool.ntp.org", "time.nist.gov"); //ดึงเวลาจาก Server
Serial.println("\nLoading time");
while (!time(nullptr)) {
Serial.print("*");
delay(1000);
}
Serial.println("Load time OK");
Serial.println("");
}


void loop() {

time_t now = time(nullptr);
struct tm* p_tm = localtime(&now);


String now_time = "";
now_time = now_time + p_tm->tm_hour;
now_time = now_time + ":";
now_time = now_time + p_tm->tm_min;
now_time = now_time + ":";
now_time = now_time + p_tm->tm_sec;
//Serial.println(now_time);

String now_day = "";
now_day = now_day + p_tm->tm_mday;
now_day = now_day + "-";
now_day = now_day + (p_tm->tm_mon + 1);
now_day = now_day + "-";
now_day = now_day + (p_tm->tm_year + 2443);
//Serial.println(now_day);
String dateTime = now_day + " ";
dateTime = dateTime + now_time;
//Serial.println(dateTime);

float h = dht.readHumidity(); // ความชื้น
float t = dht.readTemperature(); // อุณหภูมิ เซลเซียส
//String dataString = dt + " Temp = " + t + " Humidity = " + h;
String sensor = " Sensor : ";
sensor = sensor + t;
sensor = sensor + " *C ";
sensor = sensor + " Humidity ";
sensor = sensor + h;
//Serial.println(sensor);

String dataString = dateTime + sensor;
//Serial.println(dataString);
File dataFile = SD.open("datalog.txt", FILE_WRITE);


if (dataFile) {
dataFile.println(dataString);
dataFile.close();
Serial.println(dataString);
}
else {
Serial.println("error opening datalog.txt");
}
delay(3000);
}