GC9A01 display not working with esp32 or arduino

soon_to_be_engineer · May 20, 2026, 3:32pm

I bought this display from aliexpress ( Display 1.28 Inch TFT LCD Display Module Round RGB 240*240 GC9A01 Driver 4 Wire SPI Interface 240x240 PCB For Arduino, https://www.aliexpress.com/item/1005006267154807.html?spm=a2g0o.order_list.order_list_main.5.365e1802YKblUA#nav-description). I have tried to use with esp32-c3 super mini and Arduino uno and it doesn't work. What i get out of is screen with white stripes (little bit red at the edges). I have provided picture to show my wiring and problem. Got the same outcome with esp.

So the guestion is is my display broken or am I doing something really wrong?

#include <Adafruit_GFX.h>
#include <Adafruit_GC9A01A.h>
#include <SPI.h>

#define TFT_CS   10
#define TFT_DC    9
#define TFT_RST   8

Adafruit_GC9A01A tft = Adafruit_GC9A01A(TFT_CS, TFT_DC, TFT_RST);

void setup() {
  SPI.begin();

  tft.begin();
  tft.setRotation(1);

  tft.fillScreen(GC9A01A_BLUE);
}

void loop() {
}

This code one of the testest codes.

horace · May 20, 2026, 3:46pm

what pins did you use to connect the ESP32C3 supermini
I used

// ESP32-C3 supermini 
#define TFT_CS   SS     // GPIO 7  
#define TFT_MOSI MOSI   // GPIO 6
#define TFT_SCLK SCK    // GPIO 4
#define TFT_MISO -1     //MISO 

#define TFT_DC   8
#define TFT_RST  9

check the interface voltage
guide to GC9A01 states 3.3.v (logic and VCC)
connecting directly to UNO 5V logic could damage the display

soon_to_be_engineer · May 20, 2026, 3:52pm

with esp i used

#define TFT_RST 10
#define TFT_CS 9
#define TFT_DC 8
#define TFT_SDA 7
#define TFT_SCL 6

horace · May 20, 2026, 4:50pm

you need to specify MOSI and SCK pins, e.g. try using the constructor

  Adafruit_GC9A01A(int8_t _CS, int8_t _DC, int8_t _MOSI, int8_t _SCLK,
                   int8_t _RST = -1, int8_t _MISO = -1);

e.g.

#define TFT_CS   10
#define TFT_DC    9
#define TFT_RST   8
#define TFT_MOSI 7
#define TFT_SCK  6
Adafruit_GC9A01A tft = Adafruit_GC9A01A(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCK, TFT_RST);

connect BLK to 3.3V

xfpd · May 20, 2026, 5:08pm

DroneBotWorkShop uses different pins... including BACKLIGHT...

soon_to_be_engineer · May 20, 2026, 7:02pm

by using code and wire placements provided by the DroneBot Workshop link my display shows different colour of stripes but strill nothing clear just stripes :(

xfpd · May 20, 2026, 7:04pm

Verify your wiring.

soon_to_be_engineer · May 20, 2026, 7:07pm

100% sure that that my wiring is the same as in the link

xfpd · May 20, 2026, 7:16pm

Okay... but verify the pins are securely in the right holes. Breadboards and jumpers can develop intermittent issues.

horace · May 21, 2026, 4:35am

post your latest code, a schematic showing the wiring and a clear photo of the setup

soon_to_be_engineer · May 21, 2026, 6:29pm

latest code:

#include "SPI.h"
#include "Adafruit_GFX.h"
#include "Adafruit_GC9A01A.h"

#define TFT_DC 7
#define TFT_CS 10

// Hardware SPI on Feather or other boards
Adafruit_GC9A01A tft(TFT_CS, TFT_DC);

void setup() {
  Serial.begin(9600);
  Serial.println("GC9A01A Test!");

  tft.begin();

  Serial.println(F("Benchmark                Time (microseconds)"));
  delay(10);
  Serial.print(F("Screen fill              "));
  Serial.println(testFillScreen());
  delay(500);

  Serial.print(F("Text                     "));
  Serial.println(testText());
  delay(3000);

  Serial.print(F("Lines                    "));
  Serial.println(testLines(GC9A01A_CYAN));
  delay(500);

  Serial.print(F("Horiz/Vert Lines         "));
  Serial.println(testFastLines(GC9A01A_RED, GC9A01A_BLUE));
  delay(500);

  Serial.print(F("Rectangles (outline)     "));
  Serial.println(testRects(GC9A01A_GREEN));
  delay(500);

  Serial.print(F("Rectangles (filled)      "));
  Serial.println(testFilledRects(GC9A01A_YELLOW, GC9A01A_MAGENTA));
  delay(500);

  Serial.print(F("Circles (filled)         "));
  Serial.println(testFilledCircles(10, GC9A01A_MAGENTA));

  Serial.print(F("Circles (outline)        "));
  Serial.println(testCircles(10, GC9A01A_WHITE));
  delay(500);

  Serial.print(F("Triangles (outline)      "));
  Serial.println(testTriangles());
  delay(500);

  Serial.print(F("Triangles (filled)       "));
  Serial.println(testFilledTriangles());
  delay(500);

  Serial.print(F("Rounded rects (outline)  "));
  Serial.println(testRoundRects());
  delay(500);

  Serial.print(F("Rounded rects (filled)   "));
  Serial.println(testFilledRoundRects());
  delay(500);

  Serial.println(F("Done!"));
}

void loop(void) {
  for(uint8_t rotation=0; rotation<4; rotation++) {
    tft.setRotation(rotation);
    testText();
    delay(1000);
  }
}

unsigned long testFillScreen() {
  unsigned long start = micros();
  tft.fillScreen(GC9A01A_BLACK);
  yield();
  tft.fillScreen(GC9A01A_RED);
  yield();
  tft.fillScreen(GC9A01A_GREEN);
  yield();
  tft.fillScreen(GC9A01A_BLUE);
  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();
  return micros() - start;
}

unsigned long testText() {
  tft.fillScreen(GC9A01A_BLACK);
  unsigned long start = micros();
  tft.setCursor(0, 0);
  tft.setTextColor(GC9A01A_WHITE);  tft.setTextSize(1);
  tft.println("Hello World!");
  tft.setTextColor(GC9A01A_YELLOW); tft.setTextSize(2);
  tft.println(1234.56);
  tft.setTextColor(GC9A01A_RED);    tft.setTextSize(3);
  tft.println(0xDEADBEEF, HEX);
  tft.println();
  tft.setTextColor(GC9A01A_GREEN);
  tft.setTextSize(5);
  tft.println("Groop");
  tft.setTextSize(2);
  tft.println("I implore thee,");
  tft.setTextSize(1);
  tft.println("my foonting turlingdromes.");
  tft.println("And hooptiously drangle me");
  tft.println("with crinkly bindlewurdles,");
  tft.println("Or I will rend thee");
  tft.println("in the gobberwarts");
  tft.println("with my blurglecruncheon,");
  tft.println("see if I don't!");
  return micros() - start;
}

unsigned long testLines(uint16_t color) {
  unsigned long start, t;
  int           x1, y1, x2, y2,
                w = tft.width(),
                h = tft.height();

  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1 = y1 = 0;
  y2    = h - 1;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = w - 1;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t     = micros() - start; // fillScreen doesn't count against timing

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = w - 1;
  y1    = 0;
  y2    = h - 1;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = 0;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t    += micros() - start;

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = 0;
  y1    = h - 1;
  y2    = 0;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = w - 1;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t    += micros() - start;

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = w - 1;
  y1    = h - 1;
  y2    = 0;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = 0;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);

  yield();
  return micros() - start;
}

unsigned long testFastLines(uint16_t color1, uint16_t color2) {
  unsigned long start;
  int           x, y, w = tft.width(), h = tft.height();

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(y=0; y<h; y+=5) tft.drawFastHLine(0, y, w, color1);
  for(x=0; x<w; x+=5) tft.drawFastVLine(x, 0, h, color2);

  return micros() - start;
}

unsigned long testRects(uint16_t color) {
  unsigned long start;
  int           n, i, i2,
                cx = tft.width()  / 2,
                cy = tft.height() / 2;

  tft.fillScreen(GC9A01A_BLACK);
  n     = min(tft.width(), tft.height());
  start = micros();
  for(i=2; i<n; i+=6) {
    i2 = i / 2;
    tft.drawRect(cx-i2, cy-i2, i, i, color);
  }

  return micros() - start;
}

unsigned long testFilledRects(uint16_t color1, uint16_t color2) {
  unsigned long start, t = 0;
  int           n, i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  n = min(tft.width(), tft.height());
  for(i=n; i>0; i-=6) {
    i2    = i / 2;
    start = micros();
    tft.fillRect(cx-i2, cy-i2, i, i, color1);
    t    += micros() - start;
    // Outlines are not included in timing results
    tft.drawRect(cx-i2, cy-i2, i, i, color2);
    yield();
  }

  return t;
}

unsigned long testFilledCircles(uint8_t radius, uint16_t color) {
  unsigned long start;
  int x, y, w = tft.width(), h = tft.height(), r2 = radius * 2;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(x=radius; x<w; x+=r2) {
    for(y=radius; y<h; y+=r2) {
      tft.fillCircle(x, y, radius, color);
    }
  }

  return micros() - start;
}

unsigned long testCircles(uint8_t radius, uint16_t color) {
  unsigned long start;
  int           x, y, r2 = radius * 2,
                w = tft.width()  + radius,
                h = tft.height() + radius;

  // Screen is not cleared for this one -- this is
  // intentional and does not affect the reported time.
  start = micros();
  for(x=0; x<w; x+=r2) {
    for(y=0; y<h; y+=r2) {
      tft.drawCircle(x, y, radius, color);
    }
  }

  return micros() - start;
}

unsigned long testTriangles() {
  unsigned long start;
  int           n, i, cx = tft.width()  / 2 - 1,
                      cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  n     = min(cx, cy);
  start = micros();
  for(i=0; i<n; i+=5) {
    tft.drawTriangle(
      cx    , cy - i, // peak
      cx - i, cy + i, // bottom left
      cx + i, cy + i, // bottom right
      tft.color565(i, i, i));
  }

  return micros() - start;
}

unsigned long testFilledTriangles() {
  unsigned long start, t = 0;
  int           i, cx = tft.width()  / 2 - 1,
                   cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(i=min(cx,cy); i>10; i-=5) {
    start = micros();
    tft.fillTriangle(cx, cy - i, cx - i, cy + i, cx + i, cy + i,
      tft.color565(0, i*10, i*10));
    t += micros() - start;
    tft.drawTriangle(cx, cy - i, cx - i, cy + i, cx + i, cy + i,
      tft.color565(i*10, i*10, 0));
    yield();
  }

  return t;
}

unsigned long testRoundRects() {
  unsigned long start;
  int           w, i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  w     = min(tft.width(), tft.height());
  start = micros();
  for(i=0; i<w; i+=6) {
    i2 = i / 2;
    tft.drawRoundRect(cx-i2, cy-i2, i, i, i/8, tft.color565(i, 0, 0));
  }

  return micros() - start;
}

unsigned long testFilledRoundRects() {
  unsigned long start;
  int           i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(i=min(tft.width(), tft.height()); i>20; i-=6) {
    i2 = i / 2;
    tft.fillRoundRect(cx-i2, cy-i2, i, i, i/8, tft.color565(0, i, 0));
    yield();
  }

  return micros() - start;
}

wiring
Vcc = unos 3.3v
gnd = gnd
cs = 10
dc = 7
sda = 11
scl = 13

soon_to_be_engineer · May 21, 2026, 6:31pm

still displays only stripes they change as the display should change

kmin · May 21, 2026, 6:51pm

If I had to debug this, I would use only ESP. Display powered at 3V3 and connected to 5V logic MCU is not good choice.

xfpd · May 21, 2026, 10:18pm

Make your code do something small, like only one graphics function. Run-time memory might be over-full with all those functions.

horace · May 25, 2026, 6:45am

tested a Hailege 1.28" GC9A01 240x240 TFT LCD Display with a ESP32-C3 supermini using Adafruit_GC9A01A library using default SPI GPIO pins

// ESP32-C3 supermini - Hailege 1.28" GC9A01 240x240 TFT LCD Display

// using Adafruit_GC9A01A 
//  adapted from File>Examples>Adafruit_GC9A01A>graphicstest

// NOTE: for Serial IO under Tools select USB CDC on Boot 'Enabled'

#include "SPI.h"
#include "Adafruit_GFX.h"
#include "Adafruit_GC9A01A.h"

// ESP32-C3 supermini Define pins for display interface - use default SPI pins.
#define TFT_MOSI 6
#define TFT_SCK  4
#define TFT_DC  8
#define TFT_RST 9
#define TFT_CS  7
// NOTE: VCC to 3.3V

// Display constructor for default hardware SPI connection - works OK
//Adafruit_GC9A01A tft(TFT_CS, TFT_DC, TFT_RST);

// otherwise define all the pins - also works OK
Adafruit_GC9A01A tft = Adafruit_GC9A01A(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCK, TFT_RST);

void setup() {
  Serial.begin(115200);
  delay(2000);
  Serial.println("ESP32-C3 GC9A01A Test!");
  tft.begin();
#if defined(TFT_BL)
  pinMode(TFT_BL, OUTPUT);
  digitalWrite(TFT_BL, HIGH); // Backlight on
#endif // end TFT_BL

  Serial.println(F("Benchmark                Time (microseconds)"));
  delay(10);
  Serial.print(F("Screen fill              "));
  Serial.println(testFillScreen());
  delay(500);

  Serial.print(F("Text                     "));
  Serial.println(testText());
  delay(3000);

  Serial.print(F("Lines                    "));
  Serial.println(testLines(GC9A01A_CYAN));
  delay(500);

  Serial.print(F("Horiz/Vert Lines         "));
  Serial.println(testFastLines(GC9A01A_RED, GC9A01A_BLUE));
  delay(500);

  Serial.print(F("Rectangles (outline)     "));
  Serial.println(testRects(GC9A01A_GREEN));
  delay(500);

  Serial.print(F("Rectangles (filled)      "));
  Serial.println(testFilledRects(GC9A01A_YELLOW, GC9A01A_MAGENTA));
  delay(500);

  Serial.print(F("Circles (filled)         "));
  Serial.println(testFilledCircles(10, GC9A01A_MAGENTA));

  Serial.print(F("Circles (outline)        "));
  Serial.println(testCircles(10, GC9A01A_WHITE));
  delay(500);

  Serial.print(F("Triangles (outline)      "));
  Serial.println(testTriangles());
  delay(500);

  Serial.print(F("Triangles (filled)       "));
  Serial.println(testFilledTriangles());
  delay(500);

  Serial.print(F("Rounded rects (outline)  "));
  Serial.println(testRoundRects());
  delay(500);

  Serial.print(F("Rounded rects (filled)   "));
  Serial.println(testFilledRoundRects());
  delay(500);

  Serial.println(F("Done!"));
}

void loop(void) {
  for(uint8_t rotation=0; rotation<4; rotation++) {
    tft.setRotation(rotation);
    testText();
    delay(1000);
  }
}

unsigned long testFillScreen() {
  unsigned long start = micros();
  tft.fillScreen(GC9A01A_BLACK);
  yield();
  tft.fillScreen(GC9A01A_RED);
  yield();
  tft.fillScreen(GC9A01A_GREEN);
  yield();
  tft.fillScreen(GC9A01A_BLUE);
  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();
  return micros() - start;
}

unsigned long testText() {
  tft.fillScreen(GC9A01A_BLACK);
  unsigned long start = micros();
  tft.setCursor(0, 0);
  tft.setTextColor(GC9A01A_WHITE);  tft.setTextSize(1);
  tft.println("Hello World!");
  tft.setTextColor(GC9A01A_YELLOW); tft.setTextSize(2);
  tft.println(1234.56);
  tft.setTextColor(GC9A01A_RED);    tft.setTextSize(3);
  tft.println(0xDEADBEEF, HEX);
  tft.println();
  tft.setTextColor(GC9A01A_GREEN);
  tft.setTextSize(5);
  tft.println("Groop");
  tft.setTextSize(2);
  tft.println("I implore thee,");
  tft.setTextSize(1);
  tft.println("my foonting turlingdromes.");
  tft.println("And hooptiously drangle me");
  tft.println("with crinkly bindlewurdles,");
  tft.println("Or I will rend thee");
  tft.println("in the gobberwarts");
  tft.println("with my blurglecruncheon,");
  tft.println("see if I don't!");
  return micros() - start;
}

unsigned long testLines(uint16_t color) {
  unsigned long start, t;
  int           x1, y1, x2, y2,
                w = tft.width(),
                h = tft.height();

  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1 = y1 = 0;
  y2    = h - 1;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = w - 1;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t     = micros() - start; // fillScreen doesn't count against timing

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = w - 1;
  y1    = 0;
  y2    = h - 1;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = 0;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t    += micros() - start;

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = 0;
  y1    = h - 1;
  y2    = 0;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = w - 1;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);
  t    += micros() - start;

  yield();
  tft.fillScreen(GC9A01A_BLACK);
  yield();

  x1    = w - 1;
  y1    = h - 1;
  y2    = 0;
  start = micros();
  for(x2=0; x2<w; x2+=6) tft.drawLine(x1, y1, x2, y2, color);
  x2    = 0;
  for(y2=0; y2<h; y2+=6) tft.drawLine(x1, y1, x2, y2, color);

  yield();
  return micros() - start;
}

unsigned long testFastLines(uint16_t color1, uint16_t color2) {
  unsigned long start;
  int           x, y, w = tft.width(), h = tft.height();

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(y=0; y<h; y+=5) tft.drawFastHLine(0, y, w, color1);
  for(x=0; x<w; x+=5) tft.drawFastVLine(x, 0, h, color2);

  return micros() - start;
}

unsigned long testRects(uint16_t color) {
  unsigned long start;
  int           n, i, i2,
                cx = tft.width()  / 2,
                cy = tft.height() / 2;

  tft.fillScreen(GC9A01A_BLACK);
  n     = min(tft.width(), tft.height());
  start = micros();
  for(i=2; i<n; i+=6) {
    i2 = i / 2;
    tft.drawRect(cx-i2, cy-i2, i, i, color);
  }

  return micros() - start;
}

unsigned long testFilledRects(uint16_t color1, uint16_t color2) {
  unsigned long start, t = 0;
  int           n, i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  n = min(tft.width(), tft.height());
  for(i=n; i>0; i-=6) {
    i2    = i / 2;
    start = micros();
    tft.fillRect(cx-i2, cy-i2, i, i, color1);
    t    += micros() - start;
    // Outlines are not included in timing results
    tft.drawRect(cx-i2, cy-i2, i, i, color2);
    yield();
  }

  return t;
}

unsigned long testFilledCircles(uint8_t radius, uint16_t color) {
  unsigned long start;
  int x, y, w = tft.width(), h = tft.height(), r2 = radius * 2;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(x=radius; x<w; x+=r2) {
    for(y=radius; y<h; y+=r2) {
      tft.fillCircle(x, y, radius, color);
    }
  }

  return micros() - start;
}

unsigned long testCircles(uint8_t radius, uint16_t color) {
  unsigned long start;
  int           x, y, r2 = radius * 2,
                w = tft.width()  + radius,
                h = tft.height() + radius;

  // Screen is not cleared for this one -- this is
  // intentional and does not affect the reported time.
  start = micros();
  for(x=0; x<w; x+=r2) {
    for(y=0; y<h; y+=r2) {
      tft.drawCircle(x, y, radius, color);
    }
  }

  return micros() - start;
}

unsigned long testTriangles() {
  unsigned long start;
  int           n, i, cx = tft.width()  / 2 - 1,
                      cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  n     = min(cx, cy);
  start = micros();
  for(i=0; i<n; i+=5) {
    tft.drawTriangle(
      cx    , cy - i, // peak
      cx - i, cy + i, // bottom left
      cx + i, cy + i, // bottom right
      tft.color565(i, i, i));
  }

  return micros() - start;
}

unsigned long testFilledTriangles() {
  unsigned long start, t = 0;
  int           i, cx = tft.width()  / 2 - 1,
                   cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(i=min(cx,cy); i>10; i-=5) {
    start = micros();
    tft.fillTriangle(cx, cy - i, cx - i, cy + i, cx + i, cy + i,
      tft.color565(0, i*10, i*10));
    t += micros() - start;
    tft.drawTriangle(cx, cy - i, cx - i, cy + i, cx + i, cy + i,
      tft.color565(i*10, i*10, 0));
    yield();
  }

  return t;
}

unsigned long testRoundRects() {
  unsigned long start;
  int           w, i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  w     = min(tft.width(), tft.height());
  start = micros();
  for(i=0; i<w; i+=6) {
    i2 = i / 2;
    tft.drawRoundRect(cx-i2, cy-i2, i, i, i/8, tft.color565(i, 0, 0));
  }

  return micros() - start;
}

unsigned long testFilledRoundRects() {
  unsigned long start;
  int           i, i2,
                cx = tft.width()  / 2 - 1,
                cy = tft.height() / 2 - 1;

  tft.fillScreen(GC9A01A_BLACK);
  start = micros();
  for(i=min(tft.width(), tft.height()); i>20; i-=6) {
    i2 = i / 2;
    tft.fillRoundRect(cx-i2, cy-i2, i, i, i/8, tft.color565(0, i, 0));
    yield();
  }

  return micros() - start;
}

serial monitor output

ESP32-C3 GC9A01A Test!
Benchmark                Time (microseconds)
Screen fill              160939
Text                     43347
Lines                    325546
Horiz/Vert Lines         15311
Rectangles (outline)     13713
Rectangles (filled)      445550
Circles (filled)         80725
Circles (outline)        147089
Triangles (outline)      96752
Triangles (filled)       187531
Rounded rects (outline)  66783
Rounded rects (filled)   459866
Done!

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GC9A01 display not working with esp32 or arduino

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