Ceas LCD 2x16 cu termometru

 Va salut !

Si inca un montaj cu Wemos D1 mini (sper ca nu v-am plictisit !). Un ceas cu termometru (DS18B20), cu display LCD 2x16, conectare la WiFi. Functioneaza perfect, de multa vreme. 

 

//ceas cu termometru, ora iarna/vara

#ifdef ESP8266
#include 
#else
#include 
#endif

#include <Arduino.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <time.h>
#include <LiquidCrystal_I2C.h>

// Constants
#define ONE_WIRE_BUS 0
#define WIFI_RETRY_LIMIT 15
#define WIFI_RETRY_DELAY 1000
#define BACKLIGHT_PIN D5


//#define NTP_REFRESH_INTERVAL 86400000  // 24 hours in milliseconds
#define NTP_REFRESH_INTERVAL 3600000  // 1 hour in milliseconds
unsigned long lastNTPsync = 0;




// Network credentials
const char* ssid = "your_ssid";          
const char* password = "your_psw";    

// NTP settings
const char* NTP_SERVER = "ro.pool.ntp.org";
const char* TZ_INFO = "EET-2EEST-3,M3.5.0/03:00:00,M10.5.0/04:00:00";

// Custom degree symbol for LCD
byte customChar[] = {
  0x08, 0x14, 0x08, 0x07,
  0x08, 0x08, 0x07, 0x00
};

// Global objects
LiquidCrystal_I2C lcd(0x27, 16, 2);  // I2C address 0x27, 16 columns, 2 rows
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

// Global variables
tm timeinfo;
time_t now;
long unsigned lastNTPtime;
unsigned long lastEntryTime;
String StrTempC;

// Add these variables to store previous values for comparison
int prevHour = -1;
int prevMin = -1;
int prevSec = -1;
int prevDay = -1;
int prevMonth = -1;
int prevWDay = -1;
String prevTemp = "";

String readDSTemperatureC() {
  sensors.requestTemperatures();
  float tempC = sensors.getTempCByIndex(0);
  float fTempAfis = tempC;
  String sTempToStr = "";

  if (tempC == -127.00) {
    Serial.println("Failed to read from DS18B20 sensor");
    return "--";
  } else {
    Serial.print("Temperature Celsius: ");
    Serial.println(tempC, 1);
  }

  // Format temperature string with sign and padding
  if (tempC < 0.0) {
    sTempToStr = "-";
    fTempAfis *= -1; 
  } else {
    sTempToStr = " ";
  }

  if (fTempAfis < 9.9) {
    sTempToStr += " ";
  }

  return (sTempToStr + String(fTempAfis, 1));
}

bool connectToWiFi() {
  WiFi.begin(ssid, password);
  
  int incercari = 0;
  while (WiFi.status() != WL_CONNECTED && incercari < WIFI_RETRY_LIMIT) {
    delay(WIFI_RETRY_DELAY);
    Serial.print(".");
    lcd.setCursor(0, 1);
    lcd.print(incercari + 1);
    lcd.print(" / ");
    lcd.print(WIFI_RETRY_LIMIT);
    lcd.print("  ");
    incercari++;
  }
  
  if (WiFi.status() == WL_CONNECTED) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("WiFi conectat !");
    lcd.setCursor(0, 1);
    lcd.print(WiFi.localIP());
    delay(2000);
    return true;
  }
  
  return false;
}

bool getTimeReducedTraffic(int ms) {
  uint32_t start = millis();
  do {
    time(&now);
    localtime_r(&now, &timeinfo);
    delay(10);
  } while (((millis() - start) <= ms) && (timeinfo.tm_year < (2016 - 1900)));

  if (timeinfo.tm_year <= (2016 - 1900)) 
    return false;

  Serial.print("Time Now: ");  
  Serial.println(now); 
  StrTempC = readDSTemperatureC();
  return true;
}

void showTime(tm *localTime) {
  char time_output[40];
  bool timeChanged = false;
  bool dateChanged = false;
  bool tempChanged = false;


if (localTime->tm_hour >= 8 && localTime->tm_hour < 20) {
  analogWrite(BACKLIGHT_PIN, 800); // Luminozitate mare
} else {
  analogWrite(BACKLIGHT_PIN, 150); // Luminozitate redusă
}

  
  // Only update time if it has changed
  if (localTime->tm_hour != prevHour || localTime->tm_min != prevMin || localTime->tm_sec != prevSec) {
    lcd.setCursor(0, 0);
    sprintf(time_output, "%02d:%02d:%02d", localTime->tm_hour, localTime->tm_min, localTime->tm_sec);
    lcd.print(time_output);
    
    prevHour = localTime->tm_hour;
    prevMin = localTime->tm_min;
    prevSec = localTime->tm_sec;
    timeChanged = true;
    
    // Clear day of week at midnight
    if (localTime->tm_hour == 0 && localTime->tm_min == 0 && localTime->tm_sec == 0) {
      lcd.setCursor(9, 1);
      lcd.print("       ");
    }
  }

  // Only update date if it has changed
  if (localTime->tm_mday != prevDay || localTime->tm_mon != prevMonth) {
    lcd.setCursor(0, 1);
    sprintf(time_output, "%02d/%02d", localTime->tm_mday, localTime->tm_mon + 1);
    lcd.print(time_output);
    
    prevDay = localTime->tm_mday;
    prevMonth = localTime->tm_mon;
    dateChanged = true;
  }

  // Only update day of week if it has changed
  if (localTime->tm_wday != prevWDay) {
    char* dow = getDOW(localTime->tm_wday);
    lcd.setCursor(8 + (8 - strlen(dow)), 1);
    lcd.print(dow);
    
    prevWDay = localTime->tm_wday;
  }

  // Only update temperature if it has changed
  if (StrTempC != prevTemp) {
    lcd.setCursor(10, 0);
    lcd.print(StrTempC);
    
    // Display degree symbol (only if temperature changed)
    lcd.setCursor(15, 0);
    lcd.write(0);
    
    prevTemp = StrTempC;
    tempChanged = true;
  }
}

char * getDOW(uint8_t tm_wday) {
  switch (tm_wday) {
    case 1: return "    Luni";
    case 2: return "   Marti";
    case 3: return "Miercuri";
    case 4: return "     Joi";
    case 5: return "  Vineri";
    case 6: return " Sambata";
    case 0: return "Duminica";
    default: return "  Error ";
  }
}

// Loop function to update temperature 
unsigned long lastTempUpdate = 0;
const unsigned long TEMP_UPDATE_INTERVAL = 10000; // Update temperature every 10 seconds

void setup() {
  // Initialize sensors and communication
  sensors.begin();
  Serial.begin(115200);

  pinMode(BACKLIGHT_PIN, OUTPUT);
  analogWriteRange(1023); // gamă PWM
  
  // Initialize LCD 
  lcd.begin(4, 5);  // SDA = D2, SCL = D1
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Conectare WiFi..");

  // Connect to WiFi
  if (!connectToWiFi()) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("  Eroare WiFi!");
    lcd.setCursor(0, 1);
    lcd.print(" Reconectare...");
    delay(2000);
    ESP.restart();
  }

  // Configure time
  configTime(0, 0, NTP_SERVER);
  setenv("TZ", TZ_INFO, 1);

  // Get initial time
  if (!getTimeReducedTraffic(30000)) {  // Wait up to 30 seconds for initial time sync
    Serial.println("Time not set");
    ESP.restart();
  }

  // Display initial time
  showTime(&timeinfo);
  
  // Store time reference
  lastNTPtime = time(&now);
  lastEntryTime = millis();

  // Create custom character for degree symbol
  lcd.createChar(0, customChar);
  
  // Initialize previous values
  prevHour = -1;
  prevMin = -1;
  prevSec = -1;
  prevDay = -1;
  prevMonth = -1;
  prevWDay = -1;
  prevTemp = "";
  
  lcd.home();
  lcd.write(0);
  lcd.clear();
}


void loop() {
  unsigned long currentMillis = millis();

  // 1. Re-sincronizare NTP (o dată pe oră)
  if (currentMillis - lastNTPsync >= NTP_REFRESH_INTERVAL) {
    Serial.println("[NTP] Re-sincronizare...");
    configTime(0, 0, NTP_SERVER);
    setenv("TZ", TZ_INFO, 1);
    tzset();
    // Nu folosim delay mare aici, getTime va rula în background
    getTimeReducedTraffic(5000); 
    lastNTPsync = currentMillis;
  }

  // 2. Actualizare structură timp (fără contact NTP)
  // Această funcție trebuie să ruleze des pentru a menține timeinfo actualizat
  time(&now);
  localtime_r(&now, &timeinfo);

  // 3. Actualizare temperatură la intervalul definit (10 secunde)
  if (currentMillis - lastTempUpdate >= TEMP_UPDATE_INTERVAL) {
    StrTempC = readDSTemperatureC();
    lastTempUpdate = currentMillis;
  }

  // 4. Actualizare afișaj DOAR când se schimbă secunda
  // Aceasta elimină flicker-ul cauzat de scrierea repetată pe LCD
  if (timeinfo.tm_sec != prevSec) {
    showTime(&timeinfo);
    // prevSec este actualizat deja în interiorul funcției showTime din PDF-ul tău
  }
}