Graphic distortion when accessing SRAM?

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by tjoAG on Tue Aug 07 02:07:02 MST 2012
Hi All

I'm using a LPC1788 at 120 MHz, with a 16 bit SDRAM and 16 bit SRAM

The frame buffer is located in the SDRAM and I use the SRAM for some persistent data.

When I access the SRAM with relative large memory amount (+300 bytes memcpy), the display has graphics distortion. It looks like it draws shadows of the text displayed.

I guess the EMC is busy accessing the SRAM and the LCD DMA transfer is blocked.

I could split my SRAM access into smaller pieces or use DMA access to the SRAM.
That may help?

Speed up SRAM/SDRAM timing?

But is there any other solutions or am I just doing things wrong.
I'm using FreeRTOS.