How can I wire up my 5 wire SPI-Display properly to my ESP32-Wrover-e with only 4 wire SPI?

Hello guys!

I'm using the following Display (1,8 Zoll SPI TFT Display ST7735 mit 128 x 160 Pixeln – AZ-Delivery) on my ESP32-Wrover-E with ESP-IDF and I'm pretty confused about Wiring up my Display.

Thats my Pinout:

enter image description here

Now i suppose to wire my Display as followed:

ESP32 <-> st7735

3.3v <-> LED

GPIO18 <-> SCK

GPIO23 <-> MOSI

???? <-> A0(also called DC)

GPIO 4 <-> Reset

GPIO5 <-> CS;

GND <->GND

5v <-> VCC

so apparently my A0(or DC pin) is missing. This should tell me that I'm working with a 4 wire SPI(actually just 3 wire since I'm not using the MISO pin), but My Display seems not to work without a DC wire. I tried to connect it to any other GPIO without a positive result. I tried the same with an ESP32-S2-wrover-I which implements a 5 wire SPI and i got it to work. Is there a way to work around that problem?

Edit:

heres my Code

/**************************************************************************
  This is a library for several Adafruit displays based on ST77* drivers.

  Works with the Adafruit 1.8" TFT Breakout w/SD card
    ----> http://www.adafruit.com/products/358
  The 1.8" TFT shield
    ----> https://www.adafruit.com/product/802
  The 1.44" TFT breakout
    ----> https://www.adafruit.com/product/2088
  The 1.14" TFT breakout
  ----> https://www.adafruit.com/product/4383
  The 1.3" TFT breakout
  ----> https://www.adafruit.com/product/4313
  The 1.54" TFT breakout
    ----> https://www.adafruit.com/product/3787
  The 1.69" TFT breakout
    ----> https://www.adafruit.com/product/5206
  The 2.0" TFT breakout
    ----> https://www.adafruit.com/product/4311
  as well as Adafruit raw 1.8" TFT display
    ----> http://www.adafruit.com/products/618

  Check out the links above for our tutorials and wiring diagrams.
  These displays use SPI to communicate, 4 or 5 pins are required to
  interface (RST is optional).

  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing
  products from Adafruit!

  Written by Limor Fried/Ladyada for Adafruit Industries.
  MIT license, all text above must be included in any redistribution
 **************************************************************************/

#include <Adafruit_GFX.h>    // Core graphics library
#include <Adafruit_ST7735.h> // Hardware-specific library for ST7735
#include <Adafruit_ST7789.h> // Hardware-specific library for ST7789
#include <SPI.h>

/*#if defined(ARDUINO_FEATHER_ESP32) // Feather Huzzah32
  #define TFT_CS         15
  #define TFT_RST        2
  #define TFT_DC         32

#elif defined(ESP8266)
  #define TFT_CS         4
  #define TFT_RST        16                                            
  #define TFT_DC         5

#else*/
  // For the breakout board, you can use any 2 or 3 pins.
  // These pins will also work for the 1.8" TFT shield.
  #define TFT_CS        5
  #define TFT_RST       
  4 // Or set to -1 and connect to Arduino RESET pin
  #define TFT_DC        26
  
//#endif

// OPTION 1 (recommended) is to use the HARDWARE SPI pins, which are unique
// to each board and not reassignable. For Arduino Uno: MOSI = pin 11 and
// SCLK = pin 13. This is the fastest mode of operation and is required if
// using the breakout board's microSD card.

// For 1.44" and 1.8" TFT with ST7735 use:
//Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

// For 1.14", 1.3", 1.54", 1.69", and 2.0" TFT with ST7789:
//Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);


// OPTION 2 lets you interface the display using ANY TWO or THREE PINS,
// tradeoff being that performance is not as fast as hardware SPI above.
#define TFT_MOSI 23  // Data out
#define TFT_SCLK 18  // Clock out

// For ST7735-based displays, we will use this call
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCLK, TFT_RST);

// OR for the ST7789-based displays, we will use this call
//Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCLK, TFT_RST);


float p = 3.1415926;

void setup(void) {
  Serial.begin(9600);
  Serial.print(F("Hello! ST77xx TFT Test"));

  // Use this initializer if using a 1.8" TFT screen:
  tft.initR(INITR_BLACKTAB);      // Init ST7735S chip, black tab

  // OR use this initializer if using a 1.8" TFT screen with offset such as WaveShare:
  // tft.initR(INITR_GREENTAB);      // Init ST7735S chip, green tab

  // OR use this initializer (uncomment) if using a 1.44" TFT:
  //tft.initR(INITR_144GREENTAB); // Init ST7735R chip, green tab

  // OR use this initializer (uncomment) if using a 0.96" 160x80 TFT:
  //tft.initR(INITR_MINI160x80);  // Init ST7735S mini display

  // OR use this initializer (uncomment) if using a 1.3" or 1.54" 240x240 TFT:
  //tft.init(240, 240);           // Init ST7789 240x240

  // OR use this initializer (uncomment) if using a 1.69" 280x240 TFT:
  //tft.init(240, 280);           // Init ST7789 280x240

  // OR use this initializer (uncomment) if using a 2.0" 320x240 TFT:
  //tft.init(240, 320);           // Init ST7789 320x240

  // OR use this initializer (uncomment) if using a 1.14" 240x135 TFT:
  //tft.init(135, 240);           // Init ST7789 240x135
  
  // SPI speed defaults to SPI_DEFAULT_FREQ defined in the library, you can override it here
  // Note that speed allowable depends on chip and quality of wiring, if you go too fast, you
  // may end up with a black screen some times, or all the time.
  //tft.setSPISpeed(40000000);

  Serial.println(F("Initialized"));

  uint16_t time = millis();
  tft.fillScreen(ST77XX_BLACK);
  time = millis() - time;

  Serial.println(time, DEC);
  delay(500);

  // large block of text
  tft.fillScreen(ST77XX_BLACK);
  testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST77XX_WHITE);
  delay(1000);

  // tft print function!
  tftPrintTest();
  delay(4000);

  // a single pixel
  tft.drawPixel(tft.width()/2, tft.height()/2, ST77XX_GREEN);
  delay(500);

  // line draw test
  testlines(ST77XX_YELLOW);
  delay(500);

  // optimized lines
  testfastlines(ST77XX_RED, ST77XX_BLUE);
  delay(500);

  testdrawrects(ST77XX_GREEN);
  delay(500);

  testfillrects(ST77XX_YELLOW, ST77XX_MAGENTA);
  delay(500);

  tft.fillScreen(ST77XX_BLACK);
  testfillcircles(10, ST77XX_BLUE);
  testdrawcircles(10, ST77XX_WHITE);
  delay(500);

  testroundrects();
  delay(500);

  testtriangles();
  delay(500);

  mediabuttons();
  delay(500);

  Serial.println("done");
  delay(1000);
}

void loop() {
  tft.invertDisplay(true);
  delay(500);
  tft.invertDisplay(false);
  delay(500);
}

void testlines(uint16_t color) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(0, 0, x, tft.height()-1, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(0, 0, tft.width()-1, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(tft.width()-1, 0, x, tft.height()-1, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(tft.width()-1, 0, 0, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(0, tft.height()-1, x, 0, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(0, tft.height()-1, tft.width()-1, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(tft.width()-1, tft.height()-1, x, 0, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(tft.width()-1, tft.height()-1, 0, y, color);
    delay(0);
  }
}

void testdrawtext(char *text, uint16_t color) {
  tft.setCursor(0, 0);
  tft.setTextColor(color);
  tft.setTextWrap(true);
  tft.print(text);
}

void testfastlines(uint16_t color1, uint16_t color2) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t y=0; y < tft.height(); y+=5) {
    tft.drawFastHLine(0, y, tft.width(), color1);
  }
  for (int16_t x=0; x < tft.width(); x+=5) {
    tft.drawFastVLine(x, 0, tft.height(), color2);
  }
}

void testdrawrects(uint16_t color) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color);
  }
}

void testfillrects(uint16_t color1, uint16_t color2) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=tft.width()-1; x > 6; x-=6) {
    tft.fillRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color1);
    tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color2);
  }
}

void testfillcircles(uint8_t radius, uint16_t color) {
  for (int16_t x=radius; x < tft.width(); x+=radius*2) {
    for (int16_t y=radius; y < tft.height(); y+=radius*2) {
      tft.fillCircle(x, y, radius, color);
    }
  }
}

void testdrawcircles(uint8_t radius, uint16_t color) {
  for (int16_t x=0; x < tft.width()+radius; x+=radius*2) {
    for (int16_t y=0; y < tft.height()+radius; y+=radius*2) {
      tft.drawCircle(x, y, radius, color);
    }
  }
}

void testtriangles() {
  tft.fillScreen(ST77XX_BLACK);
  uint16_t color = 0xF800;
  int t;
  int w = tft.width()/2;
  int x = tft.height()-1;
  int y = 0;
  int z = tft.width();
  for(t = 0 ; t <= 15; t++) {
    tft.drawTriangle(w, y, y, x, z, x, color);
    x-=4;
    y+=4;
    z-=4;
    color+=100;
  }
}

void testroundrects() {
  tft.fillScreen(ST77XX_BLACK);
  uint16_t color = 100;
  int i;
  int t;
  for(t = 0 ; t <= 4; t+=1) {
    int x = 0;
    int y = 0;
    int w = tft.width()-2;
    int h = tft.height()-2;
    for(i = 0 ; i <= 16; i+=1) {
      tft.drawRoundRect(x, y, w, h, 5, color);
      x+=2;
      y+=3;
      w-=4;
      h-=6;
      color+=1100;
    }
    color+=100;
  }
}

void tftPrintTest() {
  tft.setTextWrap(false);
  tft.fillScreen(ST77XX_BLACK);
  tft.setCursor(0, 30);
  tft.setTextColor(ST77XX_RED);
  tft.setTextSize(1);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_YELLOW);
  tft.setTextSize(2);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_GREEN);
  tft.setTextSize(3);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_BLUE);
  tft.setTextSize(4);
  tft.print(1234.567);
  delay(1500);
  tft.setCursor(0, 0);
  tft.fillScreen(ST77XX_BLACK);
  tft.setTextColor(ST77XX_WHITE);
  tft.setTextSize(0);
  tft.println("Hello World!");
  tft.setTextSize(1);
  tft.setTextColor(ST77XX_GREEN);
  tft.print(p, 6);
  tft.println(" Want pi?");
  tft.println(" ");
  tft.print(8675309, HEX); // print 8,675,309 out in HEX!
  tft.println(" Print HEX!");
  tft.println(" ");
  tft.setTextColor(ST77XX_WHITE);
  tft.println("Sketch has been");
  tft.println("running for: ");
  tft.setTextColor(ST77XX_MAGENTA);
  tft.print(millis() / 1000);
  tft.setTextColor(ST77XX_WHITE);
  tft.print(" seconds.");
}

void mediabuttons() {
  // play
  tft.fillScreen(ST77XX_BLACK);
  tft.fillRoundRect(25, 10, 78, 60, 8, ST77XX_WHITE);
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_RED);
  delay(500);
  // pause
  tft.fillRoundRect(25, 90, 78, 60, 8, ST77XX_WHITE);
  tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_GREEN);
  tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_GREEN);
  delay(500);
  // play color
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_BLUE);
  delay(50);
  // pause color
  tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_RED);
  tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_RED);
  // play color
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_GREEN);
}

An SPI bus is 3 signals, SCK, MOSI, MISO.

Then there is a select, CS, for each device on the bus.

Some devices, such as TFT displays require extra control signals, such as DC and Reset.

SCK, MOSI and MISO are often, but not always, on specific fixed pins.

CS, DC and Reset for you display can normally be on any available pins and are defined when you enable the display in the code you have not shown us.

I added my Code to my Question. Sorry about that.

That's where your code expects the pins to be connected. ( The TFT_RST line seems to be broken )

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