DocID027496 Rev 1

11/24

AN4658

Peripheral migration guide

23

2.4

Flexible memory controller (FMC)

Table 6 presents the differences between the FMC features of STM32F429/439 and

STM32F446 lines.

User option bytes

nRST_STOP

nRST_STOP

nRST_STDBY

nRST_STDBY

WDG_SW

IWDG_SW

BOR_LEV[1:0]

BOR_LEV[2:0]

BFB2

NA

SPRMOD

SPRMOD

DB1M

NA

nWRP

nWRP

Table 5. Flash memory comparison (continued)

Flash

STM32F429xx/439xx

STM32F446xx

Table 6. FMC comparison

FMC

STM32F429xx/439xx

STM32F446xx

External memory interface

–SRAM

– NOR/NAND memories

– PSRAM (4 memory banks)

– Two banks of NAND Flash

memory with ECC hardware

– 16-bit PC Card compatible

devices

–SRAM

– NOR/NAND memories

– PSRAM (4 memory banks)

– One bank of NAND Flash

memory with ECC hardware

Data bus width

8, 16 or 32 bits

8 or 16 bits

FMC Bank

memory mapping

Bank1

4x64MB

NOR/PSRAM/SRAM

NOR/PSRAM/SRAM

Bank2

4x64MB

NAND Flash

Reserved

Bank3

4x64MB

NAND Flash

NAND Flash

Bank4

4x64MB

PC card

Reserved

SDRAM Bank1

4x64MB

SDRAM

SDRAM

SDRAM Bank2

4x64MB