Arduino / LVGL / I2C problem

How-to
#1

Description

i’m using LVGL with LovyanGFX library, on ESP32-S3 ( dev board wywy ESP32-S3-HMI-DevKit)
all works as expected, but time to time, the whole project “hang”.
i have 8 bits I2C extender and it seem the problem is here…
i read a lot of web page where LVGL is not thread safe and using some I2C devices may be a problem
(the touchscreen use the FT5X06 I2C chip)

What MCU/Processor/Board and compiler are you using?

ESP32-S3

What LVGL version are you using?

8.3.2

What do you want to achieve?

clarify the I2C problem !
not sure if i need to play with the I2C_manager file or if i need to do anything special concerning the 2C use !? (https://github.com/lvgl/lvgl_esp32_drivers

when it hang, from the terminal, i receive :
[1372241][E][wire.cpp:513] requestFrom(): i2cRead returned Error 263

here it is my config file

The code block(s) should be formatted like:

#include <LovyanGFX.hpp>

class LGFX : public lgfx::LGFX_Device
{
    lgfx::Light_PWM      _light_instance;
    lgfx::Panel_RM68120  _panel_instance;
    lgfx::Bus_Parallel16 _bus_instance;
    lgfx::Touch_FT5x06   _touch_instance;

public:

    LGFX(void)
    {
        {
            auto cfg = _bus_instance.config();

            cfg.freq_write = 30000000;

            cfg.pin_wr = 17;
            //cfg.pin_rd = 21;
            cfg.pin_rd = -1;
            cfg.pin_rs = 38;

            cfg.pin_d0  =  1;
            cfg.pin_d1  =  9;
            cfg.pin_d2  =  2;
            cfg.pin_d3  = 10;
            cfg.pin_d4  =  3;
            cfg.pin_d5  = 11;
            cfg.pin_d6  =  4;
            cfg.pin_d7  = 12;
            cfg.pin_d8  =  5;
            cfg.pin_d9  = 13;
            cfg.pin_d10 =  6;
            cfg.pin_d11 = 14;
            cfg.pin_d12 =  7;
            cfg.pin_d13 = 15;
            cfg.pin_d14 =  8;
            cfg.pin_d15 = 16;
            _bus_instance.config(cfg);
            _panel_instance.setBus(&_bus_instance);
        }

        {
            auto cfg = _panel_instance.config();
            cfg.pin_cs        =   -1;
            cfg.pin_rst       =   21;
            cfg.pin_busy      =   -1;
            cfg.dlen_16bit    = true;
            cfg.rgb_order     = true;
            cfg.memory_width  = 480;
            cfg.memory_height = 800;
            cfg.panel_width   = 480;
            cfg.panel_height  = 800;
            cfg.readable      = false;   
            _panel_instance.config(cfg);
        }

        {
            auto cfg = _touch_instance.config();
            cfg.i2c_addr   = 0x38;
            cfg.x_min      = 0;
            cfg.y_min      = 0;
            cfg.x_max      = 479;
            cfg.y_max      = 799;
            cfg.i2c_port   = 0;
            cfg.pin_sda    = GPIO_NUM_40;
            cfg.pin_scl    = GPIO_NUM_39;
            cfg.pin_int    = -1;
            cfg.freq       = 100000; // original 400000
            cfg.bus_shared = true;

            _touch_instance.config(cfg);
            _panel_instance.touch(&_touch_instance);
        }

        setPanel(&_panel_instance);
    }
};

cfg.bus_shared = true; or false don’t change anything !
i’m not sure that the problem come from the I2C driver of if it is an hardware problem on the I2C bus …

please any tips ?

thanks, regards
Phil

#2

please, someone can explain me what is the purpose of this line :

true or false don’t change anything to my problem …
all works as expected and randomly, the program crashes with

[5724725][E][wire.cpp:513] requestFrom(): i2cRead returned Error 263 I2C ERROR : 5

thanks, regards

#3

well, i just do a small project which include all (4) I2C chips.
removing any stuff concerning LVGL.
i do, in loop, some reads and writes to these chips.
after several hours, i don’t notice any problem !

so it seem that the problems occurs when LVGL use the I2C touchscreen chip …

anybody have same problem ? any tips please
did i manage anything concerning “thread safe stuff”

best wishes , regards

#4

hello,

FIY, it seem that my trouble was due to the use of the library Ticker.
removing this library and manage differently the I2C access, seem to solve my issue :o)

regards

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