A few issues with 320*480 screen with ILI9486

[2ant]

Hi, i have a new raspberry Pico W and this screen : http://www.lcdwiki.com/3.5inch_Arduino_Display-Mega2560

I used this setup :

#define USER_SETUP_ID 106
#define TFT_PARALLEL_16_BIT
#define ILI9486_DRIVER

////////////////////////////////////////////////////////////////////////////////////////
// RP2040 pins used
////////////////////////////////////////////////////////////////////////////////////////////

// These pins can be moved and are controlled directly by the library software
#define TFT_RST   22  // Reset pin
#define TFT_CS    28  // Do not define if chip select control pin permanently connected to 0V
//#define TFT_RD   -1   // Do not define, read pin must be permanently connected to 3V3

// Note: All the following pins are PIO hardware configured and driven
  #define TFT_WR   26    // Write strobe pin
  #define TFT_DC   27    // Data Command control pin

  // PIO requires these to be sequentially increasing
  #define TFT_D0    0
  #define TFT_D1    1
  #define TFT_D2    2
  #define TFT_D3    3
  #define TFT_D4    4
  #define TFT_D5    5
  #define TFT_D6    6
  #define TFT_D7    7
  #define TFT_D8    8
  #define TFT_D9    9
  #define TFT_D10  10
  #define TFT_D11  11
  #define TFT_D12  12
  #define TFT_D13  13
  #define TFT_D14  14
  #define TFT_D15  15
//

#define LOAD_GLCD   // Font 1. Original Adafruit 8 pixel font needs ~1820 bytes in FLASH
#define LOAD_FONT2  // Font 2. Small 16 pixel high font, needs ~3534 bytes in FLASH, 96 characters
#define LOAD_FONT4  // Font 4. Medium 26 pixel high font, needs ~5848 bytes in FLASH, 96 characters
#define LOAD_FONT6  // Font 6. Large 48 pixel font, needs ~2666 bytes in FLASH, only characters 1234567890:-.apm
#define LOAD_FONT7  // Font 7. 7 segment 48 pixel font, needs ~2438 bytes in FLASH, only characters 1234567890:-.
#define LOAD_FONT8  // Font 8. Large 75 pixel font needs ~3256 bytes in FLASH, only characters 1234567890:-.
#define LOAD_GFXFF  // FreeFonts. Include access to the 48 Adafruit_GFX free fonts FF1 to FF48 and custom fonts
#define SMOOTH_FONT

//#define TFT_BL   21    // LED back-light control pin
//#define TFT_BACKLIGHT_ON HIGH  // Level to turn ON back-light (HIGH or LOW)

Most examples run very fast but i have some troubles.

1- When i run this code :

#include "Free_Fonts.h" 

#include "SPI.h"
#include "TFT_eSPI.h"


TFT_eSPI tft = TFT_eSPI();

int i = 0 ;

void setup(void) {

  tft.init();
  tft.setRotation(1);
  tft.fillScreen(TFT_BLACK); 
  tft.setTextColor(TFT_WHITE, TFT_BLACK);
  
  tft.setCursor(0, 10, 1);
  tft.println("Hello World!");

  tft.setCursor(0, 20, 2);
  
  tft.println("Hello World!");
  
  
  tft.setFreeFont(TT1);     
  tft.drawString("mono1", 80, 40, 1);

  tft.setFreeFont(GLCD);  
  tft.drawString("mono2", 80, 60, 1);
           
  tft.drawString("mono3", 80, 100, 2);
                 
  tft.drawString("mono4", 80, 140, 4);

  tft.setTextColor(TFT_GREEN, TFT_BLACK);
  
  tft.setCursor(200, 10, 1);
  tft.println("Hello World!");

  tft.setCursor(200, 20, 2);
  
  tft.println("Hello World!");
  
  
  tft.setFreeFont(TT1);     
  tft.drawString("mono1", 280, 40, 1);

  tft.setFreeFont(GLCD);  
  tft.drawString("mono2", 280, 60, 1);
             
  tft.drawString("mono3", 280, 100, 2);
                 
  tft.drawString("mono4", 280, 140, 4);
}

void loop() {

}

It works fine on an ILI9341+Esp32 but the white is distorted execpt for one font on my ILI9486.

2-The Viewport_Demo example run fine but Viewport_graphictest give me a white screen.

3-Bouncy_circles give me this :

20230318_120921.mp4

4-SpriterotatingCube gives me random trailings. I can't take a picture because my screen is too bright.

Any help is appreciated.

[Bodmer]

Looks like signal integrity or it is running too fast. Try one or more of the following:

1. Keep 0V(GND) connections between display and processor short (<10cm). Use at least 3 GND wires to avoid signal integrity issues (ground bounce).
2. Try running processor at a lower clock rate. If that works then higher clock speeds can be used if the timing is adjusted. The following line in the setup file adjusts the interface speed higher numbers reduce the speed:
   #define RP2040_PIO_CLK_DIV 3
   See here for more info:
   https://github.com/Bodmer/TFT_eSPI/blob/master/User_Setup.h#L327

[Bodmer]

Assumed resolved.