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FMC bus on STM32F427

Question asked by p.charles on Feb 14, 2014
Latest reply on Apr 20, 2014 by jiang.jason.001
Dear All,

I’m currently trying to get a new board up and running.
I keep ending up in the Hardfault Handler with an undefined instruction.
Seems that the stack pointer is somehow pointing to somewhere out of the stack space.
 
My board uses an STM32F427II Rev Y Silicon.
I have on the FMC bus:-  SDRAM on bank1 (16bit wide bus)
        With some  NOR Flash (16bit wide bus)  
and also a display controller for TFT (SSD1963) mapped as SRAM.

The code has a problem somewhere in the emWin routines, which I don't have the source for.

I'm concerned that I may be suffering from the following in the errata sheet.  
 
2.8.7 FMC dynamic and static bank switching
Description
The dynamic and static banks cannot be accessed concurrently.
Workaround
Do not use dynamic and static banks at the same time. The SDRAM device must be in selfrefresh
before switching to the static memory mapped on the NOR/PSRAM or NAND/PCCard
controller. Before switching from static memory to SDRAM, issue a Normal command
to wake-up the device from self-refresh mode.
This limitation will be fixed in next silicon revision.
 
I’m using the SDRAM as memory / frame buffer for emWin so don’t have total control on when it will read from the external Flash on FMC and write out to the display?

Has anyone got a system up and running with SDRAM and a display controller on the FMC bus??

Thanks for any help given. 

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