ESP32C3 SuperMini with ST7789 TFT 76x284 px

[SinyaWeo]

pin_config.h

// Define pins for ST7789
#define TFT_CS    10  // CS pin
#define TFT_RST   8   // Reset pin
#define TFT_DC    9   // Data/Command pin
#define TFT_MOSI  7   // SPI MOSI
#define TFT_MISO  -1   // SPI MISO
#define TFT_SCLK  6   // SPI Clock
#define TFT_BL    20  // Backlight PWM pin

display.hpp

#include <pin_config.h>
#include <LovyanGFX.hpp>

class LGFX : public lgfx::LGFX_Device
{

    lgfx::Panel_ST7789 _panel_instance;

    lgfx::Bus_SPI        _bus_instance;
    
    lgfx::Light_PWM    _light_instance;

public:

  LGFX(void)
  {
    {
      auto cfg = _bus_instance.config();

      cfg.spi_host = SPI2_HOST;
      cfg.spi_mode = 0;
      cfg.freq_write = 40000000;
      cfg.freq_read  = 16000000;
      cfg.spi_3wire  = true;
      cfg.use_lock   = true;
      cfg.dma_channel = SPI_DMA_CH_AUTO;
      cfg.pin_sclk = TFT_SCLK;
      cfg.pin_mosi = TFT_MOSI;
      cfg.pin_miso = TFT_MISO;
      cfg.pin_dc   = TFT_DC;

      _bus_instance.config(cfg);
      _panel_instance.setBus(&_bus_instance);
    }

    {
      auto cfg = _panel_instance.config();

      cfg.pin_cs           =     TFT_CS;
      cfg.pin_rst          =    TFT_RST;
      cfg.pin_busy         =         -1;

      cfg.panel_width      =    76;
      cfg.panel_height     =   284;
      cfg.offset_x         =    82;
      cfg.offset_y         =    18;
      cfg.offset_rotation  =     0;
      cfg.dummy_read_pixel =     8;
      cfg.dummy_read_bits  =     1;
      cfg.readable         =  true;
      cfg.invert           = false;
      cfg.rgb_order        = false;
      cfg.dlen_16bit       = false;
      cfg.bus_shared       =  true;

      _panel_instance.config(cfg);
    }

    { 
      auto cfg = _light_instance.config();

      cfg.pin_bl = TFT_BL;
      cfg.invert = false;
      cfg.freq   = 44100;
      cfg.pwm_channel = 7;

      _light_instance.config(cfg);
      _panel_instance.setLight(&_light_instance);
    }

    setPanel(&_panel_instance);
  }
};

main.cpp

#include <pin_config.h>
#include <display.hpp>
#include <SPI.h>


LGFX display;

void setup(void)
{

  display.init();
  display.setRotation(1);
  // display.setBrightness(128); // Not working
  analogWrite(TFT_BL, 128);

  display.setTextSize(1);
  display.fillScreen(TFT_BLACK);
}

void loop(void)
{
  display.startWrite();

  display.setTextColor(TFT_WHITE);
  display.drawNumber(1, 5, 0);
  display.drawNumber(2, 5, 20);
  display.drawNumber(3, 5, 40);
  display.drawNumber(4, 5, 60);
  display.drawNumber(5, 20, 5);
  display.drawNumber(6, 40, 5);
  display.drawNumber(7, 60, 5);
  display.drawNumber(8, 80, 5);

  display.setTextColor(TFT_RED);
  display.drawString("R", 30, 16);
  display.setTextColor(TFT_GREEN);
  display.drawString("G", 40, 16);
  display.setTextColor(TFT_BLUE);
  display.drawString("B", 50, 16);
  display.drawRect(0,0,display.width(),display.height(),TFT_RED);
  display.drawRect(2,2,display.width()-4,display.height()-4,TFT_GREEN);
  display.drawRect(10,10,display.width()-20,display.height()-20,TFT_BLUE);

  display.endWrite();
}

platformio.ini

[env:lolin_c3_mini]
platform = espressif32
board = lolin_c3_mini
framework = arduino
lib_deps = 
	lovyan03/LovyanGFX
build_flags =
    -I include ; the folder containing my_display.hpp
    -I .pio/libdeps/${PIOENV}/LovyanGFX/src

Red is swapped with Blue, but the code is corrected

[bkp23]

It's right there in your display.hpp file:
cfg.rgb_order = false;

Just change it to true and Bob's your uncle.