STM32F4, CubeMX, SRAM Address Remapping (FSMC_A0, A1 … An) question.

[miliuhin9]

Posted on October 17, 2016 at 10:52

Hi,

I’m working on a project were I have to connect a camera to a custom PCB and store couple of images to external SRAM (19 bits Address length).

I’m working with the STM32F407ZGTx and I use CubeMx to generate some code, and the problem is the following:

On the custom PCB the pin PD12 is connected to the camera reset pin, so I can’t use it for FSMC_A17 address, therefore is there a possibility to make PD13 = FSMC_A17 and PE3 = FSMC_A18? (the hardware was designed in thisway)

*Note: I can’t access other pins on STM32 because there are connected to other modules.

If you have any suggestions, please leave a comment.

Thank you.

[slimen]

Posted on October 17, 2016 at 13:07

Hello Mihai,

I suggest you to review the pins assignment in your configuration compared to the datasheet of used product.So, you should be able to identify the free/usable pins following this

http://www.st.com/content/ccc/resource/technical/document/datasheet/ef/92/76/6d/bb/c2/4f/f7/DM00037051.pdf/files/DM00037051.pdf/jcr:content/translations/en.DM00037051.pdf

 in the Table 7. STM32F40xxx pin and ball definitions. Regards

[Tesla DeLorean]

Posted on October 17, 2016 at 16:53

NO

You can wire it up with additional address bits, you'll just have discontinuous regions of memory. ie a bunch of 128KB regions spread through the address space.

[stm32cube-t]

Posted on October 25, 2016 at 12:11

Hello,

STM32CubeMX highlights in blue the alternate pins when there are some available: press the ctrl key and click the pin of interest on STM32CubeMX chip view, if any alternate pins available, they will be shown in blue.

For the FSMC_A18 signal, there is no alternate pin to the PD13 pin.

Best regards