As I can understand from your peace of code you want to configure STR9 EMI in Mux mode. Well, the software of Mux_Mode_SRAM example accompanied with the AN2647 Can be a good demonstration for you (Please find it attached). You have only to modify the chip select GPIO configuration since you are using GPIO0 pins as chip select instead of GPIO5. You have also to use the appropriate wait states related to the connected memory otherwise the Read or write access operations can not be performed. Kind regards, Eris.