DFRobot display is not working?

Hello – I have a “Fermion” DFRobot 420x320 display and I can't make it work.

I am connecting to an ESP32 DevKitC-VIE (pinout here).

I have done:

VCC→5V pin on ESP32

GND→GND

SCLK→18/"VSPI_SCK"

MOSI→23/"VSPI_MOSI"

MISO→19/"VSPI_MISO"

CS→5/"VSPI_SS"

RES→16/"GPIO16"

DC→17/"GPIO17"

BLK→not connected

SCL→22/"GPIO22"/"WIRE_SCL" (not using touch screen yet)

SDA→21/"GPIO21"/"WIRE_SDA" (not using touch screen yet)

INT→not connected (not using touch screen yet)

Example code:

#include <Arduino.h>

#include "DFRobot_GDL.h" //must add "SD" and "FS" in lib_deps

#define TFT_DC 17

#define TFT_CS 5

#define TFT_RST 16

DFRobot_ILI9488_320x480_HW_SPI screen(/*dc=*/TFT_DC,/*cs=*/TFT_CS,/*rst=*/TFT_RST);

void setup() {

Serial.begin(115200);

while (!Serial) delay(10);

Serial.println("reset");

}

void loop() {

Serial.println("fill screen");

screen.fillScreen(COLOR_RGB565_RED);

Serial.println("done");

delay(1000);

}

Terminal output is as expected:

fill screen

done

fill screen

done

…but the screen never turns red.

Any help? Thanks very much!