ST STM32F40 Series

RM0090 Flexible static memory controller (FSMC)
Doc ID 018909 Rev 4 1318/1422
The FSMC registers that define the external device type and associated characteristics are
usually set at boot time and do not change until the next reset or power-up. However, it is
possible to change the settings at any time.
32.2 Block diagram
The FSMC consists of four main blocks:
● The AHB interface (including the FSMC configuration registers)
● The NOR Flash/PSRAM controller
● The NAND Flash/PC Card controller
● The external device interface
The block diagram is shown in Figure 403.
Figure 403. FSMC block diagram
AHB bus
FSMC interrupt to NVIC
NOR/PSRAM
memory
controller
HCLK
From clock
controller
NAND/PC Card
memory
controller
signals
NAND
Shared
signals
signals
NOR/PSRAM
FSMC_NE[4:1]
FSMC_NL (or NADV)
FSMC_NWAIT
FSMC_NOE
FSMC_NWE
FSMC_NIORD
FSMC_NREG
FSMC_CD
signals
PC Card
ai15591b
FSMC_NBL[1:0]
FSMC_NCE[3:2]
FSMC_INT[3:2]
FSMC_INTR
FSMC_NCE4_1
FSMC_NCE4_2
FSMC_NIOWR
FSMC_CLK
Configuration
registers
FSMC_A[25:0]
FSMC_D[15:0]