Program get stuck in draw_buf_flush

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Hi All!
I’m using LVGL with an ILI9806e-based LCD driver. LCD Connected to the stm32f769igt6 Microcontroller through DSI in Video non_Burst Mode with 8 chunks (in single Buffer mode).
it can handle drawing the first screen but can’t proceed with the other drawings. in debug mode it gets stuck in the draw_buf_flush function as shown in the attached image. it seems it can’t access the content of the second buffer. is there any way to manage LTDC and LVGL access to the framebuffer or is it helpful to use double buffering with video mode and how to implement that with lvgl. I would really appreciate suggestions on what the problem is and how to fix it

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


What LVGL version are you using?


What do you want to achieve?

fixing the problem: get stuck in Flushing the content of the draw buffer

What have you tried so far?

increasing the disp_buf1 to TFT_HOR_RES * 100

Code to reproduce

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Screenshot and/or video

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Probably you forgot to call lv_disp_flush_ready. See here Display interface — LVGL documentation

Many thanks
it works fine now