STM32F101xx, STM32F102xx, STM32F103xx, STM32F105xx and ...

RM0008
Flexible static memory controller (FSMC)
This situation occurs when a byte access is requested to a 16-bit wide Flash
memory. Clearly, the device cannot be accessed in byte mode (only 16-bit words
can be read from/written to the Flash memory) therefore:
a) Write transactions are not allowed
b) Read transactions are allowed (the controller reads the entire 16-bit memory word
and uses the needed byte only).
Configuration registers
The FSMC can be configured using a register set. See Section 19.5.6, for a detailed
description of the NOR Flash/PSRAM controller registers. See Section 19.6.7, for a detailed
description of the NAND Flash/PC Card registers.
19.4 External device address mapping
From the FSMC point of view, the external memory is divided into 4 fixed-size banks of 256
Mbytes each (Refer to Figure 161):
●
●
Bank 1 used to address up to 4 NOR Flash or PSRAM memory devices. This bank is
split into 4 NOR/PSRAM regions with 4 dedicated Chip Select.
Banks 2 and 3 used to address NAND Flash devices (1 device per bank)
● Bank 4 used to address a PC Card device
For each bank the type of memory to be used is user-defined in the Configuration register.
Figure 161. FSMC memory banks
Address
Banks
Supported memory type
6000 0000h
6FFF FFFFh
Bank 1
4 × 64 MB
NOR / PSRAM
7000 0000h
7FFF FFFFh
8000 0000h
8FFF FFFFh
Bank 2
4 × 64 MB
Bank 3
4 × 64 MB
NAND Flash
9000 0000h
9FFF FFFFh
Bank 4
4 × 64 MB
PC Card
ai14719
Doc ID 13902 Rev 9 411/995