Memory model and address space

The total amount of available addresses depends on the size of memory pointers. 32-bit machines can reference a contiguous memory space of 4 GB, which is segmented to host all the memory-mapped devices in the system. This may include:

  • Internal RAM
  • Flash memory
  • System control registers
  • Components internal to the microcontroller
  • External peripheral bus
  • Additional external RAM

Every region has a fixed physical address that may depend on the characteristics of the platform. All the locations are hardcoded, and some of them are platform-specific.

In the ARM Cortex-M, the total addressable space is divided into six macro regions. Depending on their purpose, the regions have different permissions, so that there are ...

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