Solved: 16-bit TFT ST7789V with RP2040

[shamirtahir50]

@Bodmer Something weird happens when I upload my code to RP2040. Most of the time code is uploaded and most of the time works fine.
But sometimes when I upload my code my screen resets to this.

After Several Attempts, It works fine. Is there a problem with my hardware or pin configuration.
My pin configuration is the following.

#define USER_SETUP_ID 107

////////////////////////////////////////////////////////////////////////////////////////////
// Interface
////////////////////////////////////////////////////////////////////////////////////////////
//#define TFT_PARALLEL_8_BIT
#define TFT_PARALLEL_16_BIT

////////////////////////////////////////////////////////////////////////////////////////////
// Display driver type
////////////////////////////////////////////////////////////////////////////////////////////
// #define ILI9341_DRIVER
#define ST7789_DRIVER
// #define RP2040_PIO_SPI
//#define ILI9481_DRIVER // Tested
//#define HX8357B_DRIVER // Tested
//#define HX8357C_DRIVER // Tested
//#define SSD1963_800_DRIVER
#define TFT_WIDTH 240
#define TFT_HEIGHT 320
////////////////////////////////////////////////////////////////////////////////////////////
// RP2040 pins used
////////////////////////////////////////////////////////////////////////////////////////////
#define TFT_BACKLIGHT_ON HIGH
#define TFT_BL 22
// These pins can be moved and are controlled directly by the library software
#define TFT_RST 18 // Reset pin
#define TFT_CS 19 // 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 20 // Write strobe pin
#define TFT_DC 21 // 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
//*/

////////////////////////////////////////////////////////////////////////////////////////////
// Fonts to be available
////////////////////////////////////////////////////////////////////////////////////////////
#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

Data Sheets are in the following link.

https://github.com/Bodmer/TFT_eSPI/discussions/url

[Bodmer]

Maybe there are poor connections that are intermittent.

When it has uploaded successfully then does it always run OK if the board is powered down for a few seconds and powered up again?

[Bodmer]

See #2129 for the solution.

[shamirtahir50]

@Bodmer
The solution in #2129 is not working for me I have tried all combinations,
like 133hz cpu clock
#define DIV_UNITS 2
#define DIV_UNITS 3
#define DIV_UNITS 4
Slowed clocked cpu clock to 50Hz
Also tried you new configrations at 125Hz
// #define RP2040_PIO_CLK_DIV 1 // 32ns write cycle at 125MHz CPU clock
// #define RP2040_PIO_CLK_DIV 2 // 64ns write cycle at 125MHz CPU clock
// #define RP2040_PIO_CLK_DIV 3 // 96ns write cycle at 125MHz CPU clock

I want to mention that my your basic panda png code work perfectly fine with default settings. But I am udpating portions of screen using buttons and drawing lots of bitmaps to update. To some extent it works fine But when the code exceed certian limit I shows that horible screen above.

[shamirtahir50]

Added you to my code repo one is working and other is not. Have a look at it when you got time.
I have just adding following setting to userconfig
#define USER_SETUP_ID 107
#define TFT_RGB_ORDER TFT_BGR
//#define TFT_PARALLEL_8_BIT
#define TFT_PARALLEL_16_BIT
#define ST7789_DRIVER

#define TFT_WIDTH 240
#define TFT_HEIGHT 320
////////////////////////////////////////////////////////////////////////////////////////////
// RP2040 pins used
////////////////////////////////////////////////////////////////////////////////////////////
#define TFT_BACKLIGHT_ON HIGH
#define TFT_BL 22
// These pins can be moved and are controlled directly by the library software
#define TFT_RST 18 // Reset pin
#define TFT_CS 19 // 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 20 // Write strobe pin
#define TFT_DC 21 // 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
//*/

////////////////////////////////////////////////////////////////////////////////////////////
// Fonts to be available
////////////////////////////////////////////////////////////////////////////////////////////
#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

[Bodmer]

It sounds like this is a hardware problem. Maybe there is insufficient power, poor decoupling, long connections and insufficient ground connections/plane between processor and display. Bear in mint that toggling 16 bus lines at a high rate means short wires/tracks and a ground plane are advisable. I have a display running, the wires are about 3cm long at most and I have used 4 short ground (0V) wires.

[shamirtahir50]

After reducing my connections distance on my new PCB I was able to solve this problem. You are correct long connections of data bit results in data loss. Thanks @Bodmer