STM32F429-DISC1 demo and RAM usage

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1

Hi
littlevgl stm32f429 demo

I use STM32F429-DISC1 which is pretty much the same as DISCO.

I cloned sample port but it was not compileable due to invalid target as per ac6 system workbench.
Following the text for setup works fine to build and run and importing files as per need from sample code results an OK project.

Questions:

  1. When I disable SDRAM build does not fit in RAM as your text suggests
    #define TFT_EXT_FB 0 /*Frame buffer is located into an external SDRAM*/

  2. Would it be possible to split frame buffer and send in portions to ILI controller since it has its own GRAM anyway?

Regards
/Peter

2

When I disable SDRAM build does not fit in RAM

Interesting. I thought that that board had 2MB of RAM… that should be large enough to accommodate a framebuffer.

That’s how LittlevGL works internally, so yes, it is possible.

I’m not sure if the current driver makes use of GRAM or not. That’s something @kisvegabor would have to tell you.

3

The Discovery board uses the MCU’s LTDC interface. So it is not connected via parallel port to the ILI controller but via RGB interface (HSYNC, VSYNC, colors). Therefore the MCU needs to contain the frame buffer.

On your custom board you can use parallel port to store the framebuffer in the ILI chip and allocate only a small buffer for LittlevGL.

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4

Hi all,
I played with last sample for 429Disco. I have some difficulties to port it new STM32cube and it not ported properly yet
Anyway I run it!

LVGL on Discovery kit STM32F429I-DISC1

Could you check video. I still hesitating that I run it right. Is it fitible performance?

5

The animations are running too slowly (I’d guess they need to be 2-3x faster). It might be worth double-checking that lv_tick_inc is being called at the right speed.

6

lv_tick_inc called each 1ms
I used main loop with this delay.
little awkward using loop. I should run separate thread or use interupt for that
Thanks

7

You right. I made fix. Now its running a lot better