For a project, I need some external storage. I am using STM32 and found FSMC. I learned that it can provide direct memory locations. And can write to the memory without booting specific pins (such as CE, OE, WE...). It also allows writing/reading SRAM without having to use GPIO to write registers, so it is faster. (Of course there are many advantages). If my idea is right, I think it is a very good idea to use it.
Beatriz 發表於 January 4, 2021
Whether FSMC provides any advantages depends on the STM32 you use. For example, it is of no use to any value line product (based on M2), but it can provide value on the high-performance line of the AHB bus. You did not provide details of the configuration, so we cannot help.
Gwyneth 發表於 January 4, 2021
There is no such thing as Cortex-M2, all STM32 microcontrollers have AHB, but not all support FSMC.
Sian 發表於 January 4, 2021
FSMC can be used to store data in a volatile configuration. Some (not all) STM32 maps FSMC to the address space (0x60000000). Using serial SRAM is best for storing data that does not require fast access. If it is used for values that are common in execution, it may greatly reduce the speed of the program.
You still need to configure the pins used with the FSMC and wrap the header around the interface and test.
Mercy 發表於 January 4, 2021
I just want to use it to store data from the camera so that I can process it later, as well as some images for the TFT display. I know that FSMC provides a storage unit, so its behavior is similar to writing to internal MCU RAM on the programming side. If I can understand correctly, is it faster for the MCU to let the FSMC automatically control all the pins in the hardware than trying to manually boot each command pin?
Sian 發表於 January 4, 2021
You can use it like a rom and expect it to be slow, but it will be in the address space and volatile. This means that if you use it for a TFT display and need to acquire images frequently, there will be a delay each time the image is acquired. FMSC may be faster, but it is still much slower than RAM because the data is sent serially.
