trjhtr

This is a follow-up from Digital clock with many functions

I used the review mentioned above to optimize the code, but the code can still be made better.
I made a digital clock with the use of an RTC (DS3231) and an LCD (16x2).

Current functions:

• Display time


• Display date (different formats)


• Display temperature (Celsius and Fahrenheit)


• Display day of the week (English and Dutch)


• Display week number


• Display number of day in the year


• Humidity (%)


• Dew point (Celsius and Fahrenheit)


• Change summer -> winter time (this will be done automatically, once set correctly)

Future functions:

• Menu (controlled using the buttons on the LCD shield)


• Alarm (already possible with predefining it at the start)


• Timer


• Stopwatch


• Local time of different locations

I want to implement these future functions as quickly as possible. Please feel free to give feedback and your opinion about what could be better/more efficient.

Github

Clock.ino:

#include <DS3232RTC.h> // https://github.com/JChristensen/DS3232RTC
#include <Timezone.h> // https://github.com/JChristensen/Timezone
#include <TimeLib.h> // https://github.com/PaulStoffregen/Time
#include <Streaming.h> // http://arduiniana.org/libraries/streaming/
#include <Wire.h> // https://www.arduino.cc/en/Reference/Wire
#include <LiquidCrystal.h> // https://www.arduino.cc/en/Reference/LiquidCrystal
#include <DHT.h> // https://github.com/adafruit/DHT-sensor-library
#include "Date.h"

#define DHTPIN 2 // what pin we're connected to
#define DHTTYPE DHT22 // DHT 22 (AM2302)

// initialize the library by associating any needed LCD interface pin
// with the arduino pin number it is connected to
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

DHT dht(DHTPIN, DHTTYPE); //// Initialize DHT sensor for normal 16mhz Arduino

/* EXPLANATION DIFFERENT FUNCTIONS FOR CLOCK (WILL ONLY BE USED ON THE HOMEPAGE)
 TIME
 'h' = hours
 'm' = minutes
 's' = seconds
 'a' = alarm 1 (not atm)
 'A' = alarm 2 (not atm)

 WEATHER
 'T' = temperature
 'H' = humidity (no sensor atm)
 'P' = dew point (no sensor atm)

 DATE
 'd' = day of week
 'D' = day
 'M' = month
 'S' = month (short string)
 'Y' = year
 'w' = weeknumber
 'n' = daynumber

 MISCELLANEOUS
 'l' = current location (need to create a array of enums/strings which can be used in Settings)

 DELIMTERS
 ':' = delimiter
 '-' = delimiter
 '/' = delimiter
 '.' = delimiter
 '|' = delimiter
 ' ' = delimiter
*/

const int kNumLCDCols = 16;
const int kNumLCDRows = 2;
const int kSerialBaud = 9600;
const int kLPin = 13;
const int kNumLCDChars = kNumLCDCols * kNumLCDRows;

char homepage[kNumLCDCols] = "h:m:s", "d D-M-Y", "T H", "w n";

const size_t kNumSupportedLanguages = 2;
const size_t kNumDaysPerWeek = 7;
const size_t kNumMonthsPerYear = 12;
const size_t kNumLabels = 5;
const size_t numberOfPages = (sizeof(homepage) / sizeof(char)) / kNumLCDChars;

const String days[kNumSupportedLanguages][kNumDaysPerWeek] = "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "zo", "ma", "di", "wo", "do", "vr", "za";
const String months[kNumSupportedLanguages][kNumMonthsPerYear] = "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", "jan", "feb", "mrt", "mei", "jun", "jul", "aug", "sep", "okt", "nov", "dec";
const String labels[kNumLabels] = "T", "RH", "DP", "D", "Wk";

const char degreesSymbol = 223;

enum languages_t EN, NL;
enum degreesFormats_t CELSIUS, FAHRENHEIT;
enum hourFormats_t HourFormat12, HourFormat24;

typedef struct 
 uint8_t hourFormat; // 12 or 24 hour format (AM/PM is not displayed)
 uint8_t language; // The language for several labels
 uint8_t degreesFormat; // Celsius or Fahrenheit
 boolean labels; // Display temperature, weeknumber and daynumber with label
 Settings;

Settings settings = HourFormat24, NL, CELSIUS, true;

unsigned long previousMillis = 0; // will store last time lcd was updated (page 1)
unsigned long oldMillis = 0; // will store last time lcd switched pages

TimeChangeRule myDST = "MDT", Last, Sun, Mar, 2, 2 * 60; //Daylight time/Summertime = UTC + 2 hours
TimeChangeRule mySTD = "MST", Last, Sun, Oct, 2, 1 * 60; //Standard time/Wintertime = UTC + 1 hours
Timezone myTZ(myDST, mySTD);
TimeChangeRule *tcr; //pointer to the time change rule, use to get TZ abbrev

int language_id;
int rowX = 0;
int rowY = 2;
float tem;
float hum;
float dew;

const long refreshRate = 1000;
const long switchPages = 3000;

void setup() 
 Serial.begin(9600);

 lcd.begin(kNumLCDCols, kNumLCDRows);

 // setSyncProvider() causes the Time library to synchronize with the
 // external RTC by calling RTC.get() every five minutes by default.
 setSyncProvider(RTC.get);
 if (timeStatus() != timeSet) lcd << ("RTC SYNC FAILED");

 pinMode(kLPin, OUTPUT);
 digitalWrite(kLPin, LOW);


void loop() 
 mainLoop();


void mainLoop() 
 // check to see if it's time to refresh the lcd; that is, if the difference
 // between the current time and last time you refreshed the lcd is bigger than
 // the interval at which you want to refresh the lcd.
 unsigned long currentMillis = millis();
 defineLanguageId();
 tem = dht.readTemperature();
 hum = dht.readHumidity();
 if (currentMillis - previousMillis >= refreshRate) 
 // save the last time you refreshed the lcd
 previousMillis = currentMillis;

 // display the date and time according to the specificied order with the specified settings
 displayPage(rowX, rowY);
 
 if (currentMillis - oldMillis >= switchPages) 
 oldMillis = currentMillis;

 if (rowY == numberOfPages * 2) 
 rowX = 0;
 rowY = 2;
 lcd.clear();
 else 
 rowX += 2;
 rowY += 2;
 lcd.clear();
 

 


void displayPage(int rowStart, int rowEnd) 

 time_t utc, local;
 utc = now();

 local = myTZ.toLocal(utc, &tcr);

 // calculate which day and week of the year it is, according to the current local time
 DayWeekNumber(year(local), month(local), day(local), weekday(local));

 lcd.setCursor(0, 0);
 // for-loop which loops through each row
 for (int row = rowStart; row < rowEnd; row++) 
 // if row == odd, then we are on the second line, so move the cursor of the lcd
 if (not(row % 2 == 0)) lcd.setCursor(0, 1);
 // for-loop which loops through each char in row
 for (int pos = 0; pos < 15; pos++) 
 displayDesiredFunction(row, pos, local);
 
 


void displayDesiredFunction(int row, int pos, time_t l) 
 switch (homepage[row][pos]) '
 break;
 case ' ':
 displayDelimiter(' '); // display ' '
 break;
 


void displayHours(time_t l) 
 (settings.hourFormat == HourFormat24) ? printI00(hour(l)) : printI00(hourFormat12(l));


void displayTemperature() 
 if (settings.labels) 
 lcd << labels[0] << ": ";
 
 lcdDisplayTempDew(tem);


void displayHumidity() 
 if (settings.labels) 
 lcd << labels[1] << ": ";
 
 lcd << int(hum) << "%";


void displayDewPoint() 
 dew = calculateDewPoint(tem, hum);
 if (settings.labels) 
 lcd << labels[2] << ": ";
 
 lcdDisplayTempDew(dew);


void lcdDisplayTempDew(float val) 
 (settings.degreesFormat == CELSIUS) ? lcd << int(val) << degreesSymbol << "C" : lcd << celsiusToFahrenheit(val) << (char)223 << "F";


float calculateDewPoint(float t, float h) 
 float a = 17.271;
 float b = 237.7;
 float temp = (a * t) / (b + t) + log(h * 0.01);
 float Td = (b * temp) / (a - temp);
 return Td;


void displayWeekday(int val)

 lcd << days[language_id][val - 1];


void displayNumber(char val) 
 if (val == 'd') 
 if (settings.labels == true) 
 lcd << labels[3] << ": ";
 
 printI00(DW[0]);
 
 else 
 if (settings.labels == true) 
 lcd << labels[4] << ": ";
 
 printI00(DW[1]);
 


void displayMonthShortStr(int val) 
 lcd << months[language_id][val];


void displayLocation() 
 //lcd << settings.location;


void defineLanguageId() 
 switch (settings.language) 
 case EN:
 language_id = 0;
 break;
 case NL:
 language_id = 1;
 


void printI00(int val)

 if (val < 10) lcd << '0';
 lcd << _DEC(val);


void displayDelimiter(char delim) 
 lcd << delim;


void setTimeRTC(unsigned int hours, unsigned int minutes, unsigned int seconds, unsigned int d, unsigned int m, unsigned int y) 
 setTime(hours, minutes, seconds, d, m, y);
 RTC.set(now());


int celsiusToFahrenheit(const float celsius) 
 return static_cast<int>(celsius * 1.8 + 32);

Date.h:

short DW[2];
void DayWeekNumber(unsigned int y, unsigned int m, unsigned int d, unsigned int w) 
 int ndays = 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334; // Number of days at the beginning of the month in a not leap year.
 int numLeapDaysToAdd = 0;
 if ((y % 4 == 0 && y % 100 != 0)