How to create a analog/digital NTP clock using the HELTEC ESP32 OLED WIFI board
This is a small INO file that sets up a WLAN connection, gets the time from NTP server.
The HELTEC WIFI has 0.96" OLED display that is to be driven via a library. To install this library, you need to go to
https://github.com/HelTecAutomation/Heltec_ESP32
and get that library as ZIP, then add it to your Arduino IDE via Manage libraries.
This brings you the libraries heltec.h and images.h
If you want to use images in your application, like this one has two - one for Haaga-Helia UAS and another for our 3D + Robo Lab, you need to save them as XBM files. The images are two-color images at a size of max 128*96 pixels, and look like this:
#define WiFi_Logo_width 60
#define WiFi_Logo_height 36
const unsigned char WiFi_Logo_bits[] PROGMEM = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFF, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0xE0, 0xFF, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0xFF, 0x7F, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFE, 0xFF, 0xFF, 0x01, 0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x03, 0x00, 0x00, 0x00, 0xFC, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x07, 0xC0, 0x83, 0x01, 0x80, 0xFF, 0xFF, 0xFF, 0x01, 0x00, 0x07, 0x00, 0xC0, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x0C, 0x00, 0xC0, 0xFF, 0xFF, 0x7C, 0x00, 0x60, 0x0C, 0x00, 0xC0, 0x31, 0x46, 0x7C, 0xFC, 0x77, 0x08, 0x00, 0xE0, 0x23, 0xC6, 0x3C, 0xFC, 0x67, 0x18, 0x00, 0xE0, 0x23, 0xE4, 0x3F, 0x1C, 0x00, 0x18, 0x00, 0xE0, 0x23, 0x60, 0x3C, 0x1C, 0x70, 0x18, 0x00, 0xE0, 0x03, 0x60, 0x3C, 0x1C, 0x70, 0x18, 0x00, 0xE0, 0x07, 0x60, 0x3C, 0xFC, 0x73, 0x18, 0x00, 0xE0, 0x87, 0x70, 0x3C, 0xFC, 0x73, 0x18, 0x00, 0xE0, 0x87, 0x70, 0x3C, 0x1C, 0x70, 0x18, 0x00, 0xE0, 0x87, 0x70, 0x3C, 0x1C, 0x70, 0x18, 0x00, 0xE0, 0x8F, 0x71, 0x3C, 0x1C, 0x70, 0x18, 0x00, 0xC0, 0xFF, 0xFF, 0x3F, 0x00, 0x00, 0x08, 0x00, 0xC0, 0xFF, 0xFF, 0x1F, 0x00, 0x00, 0x0C, 0x00, 0x80, 0xFF, 0xFF, 0x1F, 0x00, 0x00, 0x06, 0x00, 0x80, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 0x07, 0x00, 0x00, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0x00, 0x00, 0xF8, 0xFF, 0xFF, 0xFF, 0x7F, 0x00, 0x00, 0x00, 0x00, 0xFE, 0xFF, 0xFF, 0x01, 0x00, 0x00, 0x00, 0x00, 0xFC, 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0xFF, 0x7F, 0x00, 0x00, 0x00, 0x00, 0x00, 0xE0, 0xFF, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0xFF, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFC, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};
So, create your file in GIMP and export as XBM, then open that file and insert its contents into the images.h file as shown.
All you need to edit in this file are your network SSID and the password.