Classification by manufacturing process

Classified by access method

storage

Storage speed

reliability

Static Random Access Memory (SRAM)

Typical static RAM chip

SRAM interface characteristics

Typical dynamic RAM chip

DRAM interface features

Typical EPROM chip

ROM interface characteristics

NOR Flash

NAND FLASH

Typical dual-port static memory chip IDT7132

subtopic

Signal line connection

cpu bus load capacity

Coordination issues between CPU timing and memory chip access speed

How to choose films

•Code area (0x00000000 ~ 0x1FFFFFFF): used to store programs.

•SRAM area (0x20000000 ~ 0x3FFFFFFF): used for on-chip SRAM, which can store data and programs, and is used for firmware upgrades and other maintenance work.

•On-chip peripheral area (0x40000000 ~ 0x5FFFFFFF): used for on-chip peripherals. STM32 maps the registers of on-chip peripherals to the peripheral area, so that the registers of these peripherals can be accessed simply by accessing the memory to control the peripherals. Design work.

•The first half of the external RAM area (0x6000 0000 ~ 0x7FFF FFFF): points to on-chip RAM or off-chip RAM.

•The second half of the external RAM area (0x8000 0000 ~ 0x9FFF FFFF): points to on-chip RAM or off-chip RAM.

•The first half of the external peripheral area (0xA000 0000 ~ 0xBFFF FFFF): registers used for off-chip peripherals and also used for shared memory in multi-core systems.

•The second half of the external peripheral area (0xC000 0000 ~ 0xDFFF FFFF): registers used for off-chip peripherals and also used for shared memory in multi-core systems.

•System area (0xE000 0000 ~ 0xFFFF FFFF): used for private peripherals and chip manufacturer-specified functional areas

• The STM32 series uses Flexible Static Memory Controller (FSMC), a new memory expansion technology, for external memory expansion. It can flexibly and conveniently expand different types of large-capacity static memories according to the application needs of the system. Extension.

• FSMC supports asynchronous read/write operations of multiple data widths, and supports synchronous burst access to NOR flash memory, PSRAM, and NAND flash memory, and supports programs to run directly from the FSMC extended external memory.

•STM32 supports 1GB external RAM expansion. When expanding memory, FSMC can divide the external memory into 4 consecutive memory blocks of 256MB.