Figure 454. Fmc Block Diagram; Ahb Interface - STMicroelectronics STM32F405 Reference Manual

RM0090
37.3

AHB interface

The AHB slave interface allows internal CPUs and other bus master peripherals to access
the external memories.
AHB transactions are translated into the external device protocol. In particular, if the
selected external memory is 16- or 8-bit wide, 32-bit wide transactions on the AHB are split
into consecutive 16- or 8-bit accesses. The FMC Chip Select (FMC_NEx) does not toggle
between the consecutive accesses.

Figure 454. FMC block diagram

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Flexible memory controller (FMC)
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