Use sdram to lv_disp_draw_buf_init cause ghost?

General discussion
1

static lv_color_t buf_1[MY_DISP_HOR_RES * 480] attribute((at(0XC0000000)));
lv_disp_draw_buf_init(&draw_buf_dsc_1, buf_1, NULL, MY_DISP_HOR_RES * 480);
SDRAM Result
if this object has animeated, it will has this problem.
(but if i scroll page, it will good first time and second time problem has show it)
but if the object is static, it goold.
but if i use mcu internal ram, it good and no this problem.

2

you invalidated the D Cache?
On STM32 you can do it like this:

3

thank kisvegabor for reply.

I add it, but it still has this problem.
this problem only show in dashboard tools animated.
when i use lv_chart and add data ervey 1ms, it no ghost problem.

4

I’ve seen this issue before. Try switching the RAM to 0x60000000 like this. There is an issue with bus contention on the other address, if I recall correctly.

5

I solve this problem.
this is my sdram is broken.
i use sdram as buffer, if i save 0~10.
if sdram is good, it will save 0~10.
but my sdram will read after save will show 0,0,2,2,4,4,6,6,8,8,10,10 in memory.
i change another sdram, it fix this problem.

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