Adding RAM and FLASH to STM32F4DISCOVERY board

[drasko]

Posted on January 30, 2013 at 23:01

Hi all,

I'd like to try uClinux on STM32F4, and I really like STM32F4DISCOVERY. I have two questions :1) Would it be possible to add an external RAM and FLASH chips somehow to this boar, via some free pads / ports that are accessible ?2) Can SDRAM be used (cheaper), or PSRAM is the only solution ?BR,Drasko

[Tesla DeLorean]

Posted on January 30, 2013 at 23:19

SDRAM is totally unworkable on STM32 designs.

You'll have to review access to the FSMC pins, and if all you need actually escape. The EVAL series boards might be a better route, but obviously they are more expensive, you'll have to figure out how much your time is worth. An ARM9 might be a better solution, as it can provide for an architected cache (deal with the inherent slowness and mismatch of external memory), and many vendors support SDRAM and DDR off the shelf. For FLASH, only NOR permits execute-in-place, if that's not important consider SD Cards over external NAND.

[Tesla DeLorean]

Posted on January 31, 2013 at 03:53

If cheapness is a goal might I suggest fishing on eBay

http://www.ebay.com/itm/STM32F407-417ZG-module-HY-STM32F4xxCore144-Core-Dev-Board-/180923405960?pt=LH_DefaultDomain_0&hash=item2a1fe01688

http://www.ebay.com/itm/STM32F207ZG-module-HY-STM32F2xxCore144-Core-Dev-Board-/170874320152?pt=LH_DefaultDomain_0&hash=item27c8e73518

http://www.hotmcu.com/hystm32f4xxcore144-coredev-board-p-10.html