ESP32-S3-Touch-LCD-4.3B - tearing

[michalpankau]

Hi all,

i've build a firmware from toml file for Waveshare ESP32-S3-Touch-LCD-4.3B, but i see some tearing - single lines when scrolling lists, grids or clicking dropdown menu.

Anyone had similiar issue and solved it ?

I already tried :

• more frequent calling lv.task_handler()
• lower SPIRAM clock frequency
• single, double buffering

Any help appreciated.

Regards
Michal

[kdschlosser]

I need to see your initialization code and also the command you used to compile the binding.

Your build command should have been as follows.

python3 make.py esp32 BOARD=ESP32_GENERIC_S3 BOARD_VARIANT=SPIRAM_OCT --flash-size=16 DISPLAY=rgb_display INDEV=gt911 EXPANDER=ch422g --enable-uart-repl=n --enable-cdc-repl=y --enable-jtag-repl=n CONFIG_ESPTOOLPY_FLASHFREQ_120M=y CONFIG_IDF_EXPERIMENTAL_FEATURES=y  CONFIG_SPIRAM_SPEED_120M=y CONFIG_SPIRAM_FETCH_INSTRUCTIONS=y CONFIG_SPIRAM_RODATA=y CONFIG_ESP32S3_DATA_CACHE_LINE_64B=y CONFIG_COMPILER_OPTIMIZATION_PERF=y CONFIG_SPIRAM_XIP_FROM_PSRAM=y

also what size framebffer are you using? are you using 2 frame buffers? You should be using 2 frame buffers and those frame buffers should be sized as

display_width * display_height * bytes_per_pixel / 10 

If memory serves you should have the display frequency set to 12.5 mHz (12500000 Hz)

are you using 16 bit color or 24 bit color?

[kdschlosser]

also you should not be calling lv.task_handler() at all. That is all handled internally.

I really need to see the code you are using in order to help.

[michalpankau]

Kevin,

I build a firmware with command

python3 make.py --toml display_configs/Waveshare-ESP32-S3-Touch-LCD-4.3B.toml

From REPL

LVGL (9.4.0) MicroPython (1.27.0-preview) Binding compiled on 2025-12-10; Generic ESP32S3 module with Octal-SPIRAM with ESP32S3

my output display.py file in firmware

from micropython import const
import lvgl as lv


_DISPLAY_BUS_DATA0 = const(14)
_DISPLAY_BUS_DATA1 = const(38)
_DISPLAY_BUS_DATA2 = const(18)
_DISPLAY_BUS_DATA3 = const(17)
_DISPLAY_BUS_DATA4 = const(10)
_DISPLAY_BUS_DATA5 = const(39)
_DISPLAY_BUS_DATA6 = const(0)
_DISPLAY_BUS_DATA7 = const(45)
_DISPLAY_BUS_DATA8 = const(48)
_DISPLAY_BUS_DATA9 = const(47)
_DISPLAY_BUS_DATA10 = const(21)
_DISPLAY_BUS_DATA11 = const(1)
_DISPLAY_BUS_DATA12 = const(2)
_DISPLAY_BUS_DATA13 = const(42)
_DISPLAY_BUS_DATA14 = const(41)
_DISPLAY_BUS_DATA15 = const(40)
_DISPLAY_BUS_HSYNC = const(46)
_DISPLAY_BUS_VSYNC = const(3)
_DISPLAY_BUS_DE = const(5)
_DISPLAY_BUS_PCLK = const(7)
_DISPLAY_BUS_FREQ = const(12000000)
_DISPLAY_BUS_HSYNC_FRONT_PORCH = const(8)
_DISPLAY_BUS_HSYNC_BACK_PORCH = const(8)
_DISPLAY_BUS_HSYNC_PULSE_WIDTH = const(4)
_DISPLAY_BUS_HSYNC_IDLE_LOW = const(True)
_DISPLAY_BUS_VSYNC_FRONT_PORCH = const(8)
_DISPLAY_BUS_VSYNC_BACK_PORCH = const(8)
_DISPLAY_BUS_VSYNC_PULSE_WIDTH = const(4)
_DISPLAY_BUS_VSYNC_IDLE_LOW = const(False)
_DISPLAY_BUS_DE_IDLE_HIGH = const(False)
_DISPLAY_BUS_PCLK_IDLE_HIGH = const(True)
_DISPLAY_BUS_PCLK_ACTIVE_LOW = const(True)
_I2C_BUS_HOST = const(0)
_I2C_BUS_SCL = const(9)
_I2C_BUS_SDA = const(8)
_I2C_BUS_FREQ = const(400000)
_DISPLAY_WIDTH = const(800)
_DISPLAY_HEIGHT = const(480)

import lcd_bus

display_bus = lcd_bus.RGBBus(
    data0=_DISPLAY_BUS_DATA0,
    data1=_DISPLAY_BUS_DATA1,
    data2=_DISPLAY_BUS_DATA2,
    data3=_DISPLAY_BUS_DATA3,
    data4=_DISPLAY_BUS_DATA4,
    data5=_DISPLAY_BUS_DATA5,
    data6=_DISPLAY_BUS_DATA6,
    data7=_DISPLAY_BUS_DATA7,
    data8=_DISPLAY_BUS_DATA8,
    data9=_DISPLAY_BUS_DATA9,
    data10=_DISPLAY_BUS_DATA10,
    data11=_DISPLAY_BUS_DATA11,
    data12=_DISPLAY_BUS_DATA12,
    data13=_DISPLAY_BUS_DATA13,
    data14=_DISPLAY_BUS_DATA14,
    data15=_DISPLAY_BUS_DATA15,
    hsync=_DISPLAY_BUS_HSYNC,
    vsync=_DISPLAY_BUS_VSYNC,
    de=_DISPLAY_BUS_DE,
    pclk=_DISPLAY_BUS_PCLK,
    freq=_DISPLAY_BUS_FREQ,
    hsync_front_porch=_DISPLAY_BUS_HSYNC_FRONT_PORCH,
    hsync_back_porch=_DISPLAY_BUS_HSYNC_BACK_PORCH,
    hsync_pulse_width=_DISPLAY_BUS_HSYNC_PULSE_WIDTH,
    hsync_idle_low=_DISPLAY_BUS_HSYNC_IDLE_LOW,
    vsync_front_porch=_DISPLAY_BUS_VSYNC_FRONT_PORCH,
    vsync_back_porch=_DISPLAY_BUS_VSYNC_BACK_PORCH,
    vsync_pulse_width=_DISPLAY_BUS_VSYNC_PULSE_WIDTH,
    vsync_idle_low=_DISPLAY_BUS_VSYNC_IDLE_LOW,
    de_idle_high=_DISPLAY_BUS_DE_IDLE_HIGH,
    pclk_idle_high=_DISPLAY_BUS_PCLK_IDLE_HIGH,
    pclk_active_low=_DISPLAY_BUS_PCLK_ACTIVE_LOW
)


import i2c

i2c_bus = i2c.I2C.Bus(
    host=_I2C_BUS_HOST,
    scl=_I2C_BUS_SCL,
    sda=_I2C_BUS_SDA,
    freq=_I2C_BUS_FREQ
)

import gt911

indev_device = i2c.I2C.Device(
    bus=i2c_bus,
    dev_id=gt911.I2C_ADDR,
    reg_bits=gt911.BITS
)



import rgb_display

display = rgb_display.RGBDisplay(
    data_bus=display_bus,
    display_width=_DISPLAY_WIDTH,
    display_height=_DISPLAY_HEIGHT,
    color_space=lv.COLOR_FORMAT.RGB565
)

display.set_power(True)
display.init()
display.set_backlight(100)

import gt911

indev = gt911.GT911(device=indev_device)

import task_handler

task_handler.TaskHandler()

i can confirm i do not call lv.task_handler()

what i did is to modify display.py with :

1. change from 12MHz to 10MHz

_DISPLAY_BUS_FREQ = const(10000000)

2. add buffers

_BUFFER = const(38400) #1/10
_BUF1 = rgb_bus.allocate_framebuffer(_BUFFER, lcd_bus.MEMORY_SPIRAM)
_BUF2 = rgb_bus.allocate_framebuffer(_BUFFER, lcd_bus.MEMORY_SPIRAM)

display = rgb_display.RGBDisplay(
    data_bus=display_bus,
    display_width=_DISPLAY_WIDTH,
    display_height=_DISPLAY_HEIGHT,
    frame_buffer1=_BUF1,
    frame_buffer2=_BUF2,
    color_space=lv.COLOR_FORMAT.RGB565
)

3. use 1 buffer

_BUFFER = const(38400) #1/10
_BUF1 = rgb_bus.allocate_framebuffer(_BUFFER, lcd_bus.MEMORY_SPIRAM)

display = rgb_display.RGBDisplay(
    data_bus=display_bus,
    display_width=_DISPLAY_WIDTH,
    display_height=_DISPLAY_HEIGHT,
    frame_buffer1=_BUF1,
    color_space=lv.COLOR_FORMAT.RGB565
)

Regards,
Michal

[kdschlosser]

OK edit the toml file and under the line CONFIG_COMPILER_OPTIMIZATION_PERF='y' add a new line that has CONFIG_SPIRAM_XIP_FROM_PSRAM=y

use the generated display file how it is. to not modify anything. It handles setting the frame buffers how they need to be set...

RGB displays are not the best kind of display to run on the ESP32. especially ones that are 800 x 480 resolution. It requires a lot of work to update a display of that size.

If you still have issues then modify the generated display file and add in allocation the frame buffers yourself. You are going to more than likely want to increase the size of them.

[michalpankau]

Kevin,

i did some tests with no luck

1. add CONFIG_SPIRAM_XIP_FROM_PSRAM=y to firmware
2. add following config to display.py (with firmware from 1)

_DISPLAY_BUS_FREQ = const(12500000)

import rgb_display

# Partial buffer size (~1/10 of display)
# _BUFFER_SIZE = _DISPLAY_WIDTH * _DISPLAY_HEIGHT * 2bytes / 10
_BUFFER_SIZE = const(153600)

# Allocate partial buffers for double-buffering
fb1 = display_bus.allocate_framebuffer(_BUFFER_SIZE, lcd_bus.MEMORY_SPIRAM)
fb2 = display_bus.allocate_framebuffer(_BUFFER_SIZE, lcd_bus.MEMORY_SPIRAM)

display = rgb_display.RGBDisplay(
    data_bus=display_bus,
    display_width=_DISPLAY_WIDTH,
    display_height=_DISPLAY_HEIGHT,
    frame_buffer1=fb1,
    frame_buffer2=fb2,
    color_space=lv.COLOR_FORMAT.RGB565
)

p.s. did you consider upgrading toml_reader.py to enable extender from toml file. Now it's not added to display.py.

[CH422G.io_expander]
device = "io_expander_device"

[I2C.Device.io_expander_device]
bus = "i2c_bus"
dev_id = "ch422g.I2C_ADDR"
reg_bits = "ch422g.BITS"

Regards,
Michał