AnsweredAssumed Answered

Strange SDRAM behavior on BF537

Question asked by Der.Chef on Apr 25, 2013
Latest reply on May 16, 2013 by Der.Chef

Hi everyone,

 

I'm currently working on my master thesis and i'm using a Silica FireCracker BF537E-DA board. A BF537E core module from Bluetechnix with 32 MB SDRAM is installed on this board.
The board works but i have some heavy problems using the external sdram. All my code written is working correctly as long as i don't use the sdram. I documented one of my problems on the pctures below. I created an LDF-File with the wizard and default settings. To keep it simple i create an array and place it on the sdram:

 

section("sdram0_bank3") volatile short SPORT_DMA_TxBuffer[1024];

 

When i try to fill the array from the beginning with a simple for-loop then i get very strange behavior. The data is written on i = 0 (as desired) the value appears on position i = 512 (not desired) at the same time. This continues with i = 1 (as desired) and i = 513 (not desired) and so on. When i reach the position i = 512 the new data is written on i = 512 as desired and not desired on i = 0. It's little bit difficult to describe so a made the pictures.

 

1.png

 

2.png

 

3.png

 

4.png

 

511.png

 

540.png

 

What's going on there?

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