In the project will be making a clock project without RTC, it will be taking time from internet using wifi and it will display it on st7735 display.

things needed

esp8266

tft display

jumper cables

usb for programming

NTP stands for Network Time Protocol and it is a networking protocol for clock synchronization between computer systems. In other words, it is used to synchronize computer clock times in a network.

There are NTP servers like pool.ntp.org that anyone can use to request time as a client. In this case, the ESP8266 is an NTP Client that requests time from an NTP Server (pool.ntp.org).

We’ll use the NTPClient library to get time. In your Arduino IDE, go to Sketch > Library > Manage Libraries. The Library Manager should open.

Search for NTPClient and install the library by Fabrice Weinber as shown in the following image.

The NTPClient Library comes with the following functions to return time:

getDay() – returns an int number that corresponds to the the week day (0 to 6) starting on Sunday;

getHours() – returns an int number with the current hour (0 to 23) in 24 hour format;

getMinutes() – returns an int number with the current minutes (0 to 59);

getSeconds() – returns an int number with the current second;

getEpochTime() – returns an unsigned long with the epoch time (number of seconds that have elapsed since January 1, 1970 (midnight GMT);

getFormattedTime() – returns a String with the time formatted like HH:MM:SS;

This library doesn’t come with functions to return the date, but we’ll show you in the code how to get the date (day, month and year).

After downloading the file just add st7735 library and NTPClient library into your arduino ide

Then open the NTP_CLK sketch

And before uploading the code just edit it and you need to provide your wifi ssid and password in it and then

You need to set offsettime for me it is 19800

Because my timezone is utc+5:30 so

this is a code for esp8266 NTP clock, which will get time from NTP server which means you don't need an RTC to get the time. There are three codes provided here : 1: simple code to print time from NTP server in serial monitor 2: printing time on 1.8" SPI ST7735 TFT display 3: printing time on 1.8" SPI TFT ST7735 display with custom 7seg font and the font file (.h) is already added in this repo.

Get Time

Then, we can use the functions provided by the library to get time. For example, to get the epoch time:

unsigned long epochTime = timeClient.getEpochTime();

Serial.print("Epoch Time: ");

Serial.println(epochTime);

The getFormattedTime() function returns the time in HH:MM:SS format.

String formattedTime = timeClient.getFormattedTime();

Serial.print("Formatted Time: ");

Serial.println(formattedTime);

You can get the hours, minutes or seconds separately using the getHours(), getMinutes() and getSeconds() functions as follows:

int currentHour = timeClient.getHours();

Serial.print("Hour: ");

Serial.println(currentHour);

int currentMinute = timeClient.getMinutes();

Serial.print("Minutes: ");

Serial.println(currentMinute);

int currentSecond = timeClient.getSeconds();

Serial.print("Seconds: ");

Serial.println(currentSecond);

Get Date

The getDay() function returns a number from 0 to 6, in which 0 corresponds to Sunday and 6 to Saturday. So, we can access the week day name from the array we’ve created previously as follows

String weekDay = weekDays[timeClient.getDay()];

Serial.print("Week Day: ");

Serial.println(weekDay);

The NTP Client doesn’t come with functions to get the date. So, we need to create a time structure (struct tm) and then, access its elements to get information about the date.

struct tm *ptm = gmtime ((time_t *)&epochTime);

The time structure contains the following elements:

tm_sec: seconds after the minute;

tm_min: minutes after the hour;

tm_hour: hours since midnight;

tm_mday: day of the month;

tm_year: years since 1900;

tm_wday: days since Sunday;

tm_yday: days since January 1;

tm_isdst: Daylight Saving Time flag;

tm structure documentation.

UTC +5:30=5.5*60*60=19800

UTC+1=1*60*60=3600

CALCULATE your timezone and edit it and then upload the code.

After uploading the code it will look better as shown but to make it more professional lets make a pcb as already uploaded gerber file it is with code files and then i uploaded my gerber to https://pcbway.com , you can also get your pcb from there. And after soldering everything it will look like my image.

make sure before uploading the code you edited the offsetTime which will select your country timezone as for me it is 19800 since my time standerd is UTC+5:30=5.56060=19800 say yours is UTC+1=16060=3600 so refer these two examples to get offset time for your time standerd.