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FSMC with Synchronous Memory

Question asked by Doherty.Rowan.001 on Sep 2, 2014
Latest reply on Sep 11, 2014 by Doherty.Rowan.001
I'm trying to connect from an STM32's FSMC to block-RAM inside an FPGA. Since this type of memory is synchronous, I need to expose the FSMC clock to the FPGA.
At the moment I have an STM32F4-Discovery connected to a logic analyser to check that the signals are behaving as I would expect. 

When I configure the device as an asynchronous SRAM as per the STM324xG_EVAL in the STM32Cube library examples, I can see the pins toggling basically as I would expect, but with no activity on the clock line. I'm finding the documentation extremely vague for synchronous operations, can I can't find any examples.

But, when I change memory to burst mode, I can see activity on the clock line, but nothing else toggles. I'm not sure if this is because the FSMC module is waiting for an extra signal or something, but I can't get it to write to the bus; I simply see the FSMC_CLK pin toggling.

I have several questions that I think will help with my problem:

       
  1. Is "burst mode" the only mode that uses the clock.
  2.    
  3. I see that there are three types of memory: SRAM, PSRAM and NOR types. However, the library only has "stm32f4xx_hal_nor.c" and "stm32f4xx_hal_sram.c". Is there another source file for "PSRAM"? Do I use the NOR functions or the SRAM functions to configure for PSRAM mode?
  4.    
  5. If I configure for synchronous operation (burst mode?), do I need to do anything with the WAIT signals? I currently have it disabled, but do I need to enable it?

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