
DocID024597 Rev 5
453/1830
RM0351
Flexible static memory controller (FSMC)
471
SRAM/NOR-Flash chip-select timing registers 1..4 (FMC_BTR1..4)
Address offset: 0x04 + 8 * (x – 1), x = 1..4
Reset value: 0x0FFF FFFF
This register contains the control information of each memory bank, used for SRAMs,
PSRAM and NOR Flash memories.If the EXTMOD bit is set in the FMC_BCRx register, then
this register is partitioned for write and read access, that is, 2 registers are available: one to
configure read accesses (this register) and one to configure write accesses (FMC_BWTRx
registers).
Bit 8
BURSTEN:
Burst enable bit.
This bit enables/disables synchronous accesses during read operations. It is valid only for
synchronous memories operating in burst mode:
0: Burst mode disabled (default after reset). Read accesses are performed in asynchronous mode.
1: Burst mode enable. Read accesses are performed in synchronous mode.
Bit 7 Reserved, must be kept at reset value
Bit 6
FACCEN:
Flash access enable
Enables NOR Flash memory access operations.
0: Corresponding NOR Flash memory access is disabled
1: Corresponding NOR Flash memory access is enabled (default after reset)
Bits 5:4
MWID[1:0]:
Memory data bus width.
Defines the external memory device width, valid for all type of memories.
00: 8 bits
01: 16 bits (default after reset)
10: reserved
11: reserved
Bits 3:2
MTYP[1:0]:
Memory type.
Defines the type of external memory attached to the corresponding memory bank:
00: SRAM (default after reset for Bank 2...4)
01: PSRAM (CRAM)
10: NOR Flash/OneNAND Flash (default after reset for Bank 1)
11: reserved
Bit 1
MUXEN:
Address/data multiplexing enable bit.
When this bit is set, the address and data values are multiplexed on the data bus, valid only with
NOR and PSRAM memories:
0: Address/Data nonmultiplexed
1: Address/Data multiplexed on databus (default after reset)
Bit 0
MBKEN:
Memory bank enable bit.
Enables the memory bank. After reset Bank1 is enabled, all others are disabled. Accessing a
disabled bank causes an ERROR on AHB bus.
0: Corresponding memory bank is disabled
1: Corresponding memory bank is enabled