RA8875 7'' display does not work

kyrpav · September 4, 2022, 5:59pm

RA8875 seems that does not work with lvgl. Something is problematic with the setup i suppose. The problems that i have is the one presented but not solved in the github issue

github.com/lvgl/lv_port_esp32

RA8875 7" LCD not functioning with this library (white screen random lines) - ER-TFTM070-5 screen from BuyDisplay

opened 06:11PM - 07 Jan 21 UTC

closed 09:03PM - 11 Jul 21 UTC

jhancharler

stale

We use GitHub issues for development related discussions. Please use the [forum…](https://forum.littlevgl.com/) to ask questions. **Issue** After setting up the device pins on menuconfig and flashing the basic example (with some modifications that I will explain below), I see a white screen with some coloured lines. Like this: ![ra8875](https://user-images.githubusercontent.com/56173677/103928034-2b713500-5113-11eb-953e-422efd71b3fd.gif) **Code to reproduce the issue** Basic example code as found in the latest release, using latest IDF (v4.3) however I modified the ra8875.c library to turn on the internal PWM because the LCD would not turn on otherwise. ``` // These are the PWM registers that I defined in the .h file //#define RA8875_REG_P1CR (0x8A) //#define RA8875_REG_P1DCR (0x8B) void ra8875_configure_clocks(bool high_speed) { uint8_t val; val = high_speed ? ((CONFIG_LV_DISP_RA8875_PLLDIVM << 7) | CONFIG_LV_DISP_RA8875_PLLDIVN) : 0x07; ra8875_write_cmd(RA8875_REG_PLLC1, val); // PLL Control Register 1 (PLLC1) vTaskDelay(1); val = high_speed ? CONFIG_LV_DISP_RA8875_PLLDIVK : 0x03; ra8875_write_cmd(RA8875_REG_PLLC2, val); // PLL Control Register 2 (PLLC2) vTaskDelay(1); // Changes start here (starting PWM) uint8_t P1CR_config = 0x82; //pwm enable, disable level = 0, pwm1 function, clk/8 val = high_speed ? P1CR_config : 0x82; ra8875_write_cmd(RA8875_REG_P1CR, val); // P1CR register vTaskDelay(1); uint8_t P1DCR_config = 0xfe; //pwm duty cycle 255 = 256/256 duty. 0xff == full brightness val = high_speed ? P1DCR_config : 0x80; ra8875_write_cmd(RA8875_REG_P1DCR, val); // P1DCR register vTaskDelay(1); // changes end here ra8875_write_cmd(RA8875_REG_PCSR, PCSR_VAL); // Pixel Clock Setting Register (PCSR) vTaskDelay(DIV_ROUND_UP(20, portTICK_RATE_MS)); } ``` **Expected Results** The basic demo to show on the display. **Actual Results** See image above. **ESP32 Chip version** ESP32-D0WD (revision 1) **ESP-IDF version** 4.3 **Development kit used** ESP32-DevkitC v4 **Development machine OS** Ubuntu v20.04.1 **Compilation warnings/errors (if available)** None **If possible, copy the compilation log into a file and attach it here**

As summary in my case i just have black screen.

When using SIO and full-duplex the memory clear operation times out, which warns the controller may be unresponsive except if the SPI frequency small like 1MHz where not error comes but program does nothing expect logging the it Enables Display.
When using DIO/QIO and half-duplex, the error about DMA comes up

Someone else is saying that there is problem with SPI Mode where there is not setup for RA8875 in lvgl_spi_conf.h so program takes SPI Mode 0. He says that proper mode is 3 but i do not see also this working

#if defined (CONFIG_LV_TFT_DISPLAY_CONTROLLER_ST7789)
#define SPI_TFT_SPI_MODE    (2)
#else
#define SPI_TFT_SPI_MODE    (0)
#endif

I am using v4.3 esp-idf and the lv_esp32_port example to check how it works.

Is there any solution cause the github issue is closed before one year

kyrpav · September 17, 2022, 6:30pm

I have managed to use esp32 on Adafruit RA8875 arduino example by using vspi pins. lv_esp32_port with the same pins does not work. I compressed ino and lib to sent it. I saw some differencies in the initialize function from the initial setup but they did not work . is it possible to get a more experience eye to look at it?
Adafruit_RA8875.zip (407.5 KB)

kyrpav · September 18, 2022, 4:29pm

My solution in the basic sdconfig and in ra8875 setup is
sdkconfig.zip (12.5 KB)

I would appreciate some help, or it seems that i have to leave lvgl and try to find different solution

osw · January 9, 2023, 3:26am

Hi there,

I’m also using ESP32 with version C3-12F and RA8875. After a month I could make it work, it quite confusing at first but I manage to display in RA8875 but it still slows for drawing. You could try using LVGL Arduino example. Here’s the example code that I have been used that successfully compiled and display widget examples:
ra8875_lvgl.c.txt (4.1 KB)

Ps.: I make my own code for driving RA8875 by referring to RA8875_Adafruit Source code and datasheet, this help me to understand better how RA8875 works, and we can customize the SPI etc.