The Definitive Guide to the ARM Cortex-M3

CHAPTER 5 Memory Systems

In This Chapter:

• Memory System Features Overview

• Memory Maps

• Memory Access Attributes

• Default Memory Access Permissions

• Bit-Band Operations

• Unaligned Transfers

• Exclusive Accesses

• Endian Mode

Memory System Features Overview

The Cortex-M3 processor has a different memory architecture from that of traditional ARM processors. First, it has a predefined memory map that specifies which bus interface is to be used when a memory location is accessed. This feature also allows the processor design to optimize the access behavior when different devices are accessed.

Another feature of the memory system in the Cortex-M3 is the bit-band support. This provides atomic operations to bit data in memory or peripherals. ...