Embedded Systems (Hobbyist)

Ever since I was a kid, I remember asking my maternal/paternal aunt and my own mom for some gadgets that had gone wrong and if I could open it up and see what was inside. I remember my dad working in telecommunication company PTCL locally and we used to have a lot of telephone headsets home. The joy of opening one, taking the magnet out and realizing the big pastic body was nothing but a facade and all that mattered and lived inside was a tiny circuit, some wires, and a membrane numberpad for dialing.

So, yesterday, after a long time of wishing and lusitng over some electronic circuits over on Ali Express, I finally got my hands on one. It is an ESP32S microcontroller with a display panel. Tiny, yet quite capable. To my surprise, I was not aware that I was gonna need to learn more C or brush up even the 2 courses I took back in my college days.

For anyone reading and mainly for my own understanding I am gonna run through the setup on this and how did I figure out what worked:

#include <Arduino.h>
#include <Arduino_GFX_Library.h>
constexpr uint8_t TFT_BL = 14;
Arduino_DataBus *bus = new Arduino_ESP32SPI(
    11,               // DC
    10,               // CS
    12,               // SCK
    13,               // MOSI
    GFX_NOT_DEFINED   // MISO (unused)
);
Arduino_GFX *gfx = new Arduino_ST7789(
    bus,
    1,                // RST
    1,                // Rotation: landscape
    true,             // IPS
    170,              // Native width
    320,              // Native height
    35, 0,            // Column / row offsets 1
    35, 0             // Column / row offsets 2
);
void setup()
{
    pinMode(TFT_BL, OUTPUT);
    digitalWrite(TFT_BL, HIGH);
    gfx->begin();
 // Clear the entire screen to black
    gfx->fillScreen(RGB565_BLACK);
    gfx->setTextColor(0xFFFF);
    gfx->setTextSize(2);
    gfx->setTextWrap(false);
    gfx->setCursor(100, 75);
    gfx->println("Hello World!");    
}
void loop()
{
}