Using SDRAM as ExtFlashSection for TouchGFX

Hello!

I successfully created a user interface on an STM32F469I-DISCO which looks rather neat.

However, with only a few icons it uses, the memory is already about 80% full. That's why I tried to use the embedded SDRAM to store the data required for the layout. I added the SDRAM to the linker file using the following :

SDRAM		(xrw)	: ORIGIN = 0xC0000000, 	LENGTH = 16M

The embedded SDRAM is supposed to be 128Mbit but I test with only 16Mbit.

However, when I place the ExtFlashSection for TouchGFX inside the SDRAM with

ExtFlashSection :
	{
		*(ExtFlashSection ExtFlashSection.*)
		*(.gnu.linkonce.r.*)
 . = ALIGN(0x4);
	} >SDRAM
 
 BmpCacheSection (NOLOAD) : { *(BmpCacheSection) } >SDRAM
 TouchGFX_Framebuffer (NOLOAD) : { *(TouchGFX_Framebuffer) } >SDRAM
 TouchGFX_Framebuffer1 (NOLOAD) : { *(TouchGFX_Framebuffer1) } >SDRAM
 TouchGFX_Framebuffer2 (NOLOAD) : { *(TouchGFX_Framebuffer2) } >SDRAM

the display shows crap.

I attached two pictures, one which shows how the screen is supposed to look and one showing the display after placing stuff inside the SDRAM. Did anyone encounter this issue before? When yes, what had been done?

Thank you a lot,

Nicolas Kieger.