Memory Modes
4-2
4.1 Memory Mode Types and Selection
This microcontroller has a 32-bit linear address space of up to 4 Gbytes.
The address space is comprised of internal memory space built into the chip and external memory space located
outside the chip. The internal memory space can be further divided into internal data space which allows high-
speed data access, internal I/O space which contains the I/O ports and control registers built into the chip, and
internal instruction space which mainly contains instructions.
Instructions can only be located in the internal instruction space within the internal memory space and in the
external memory space. Data can be located in all address spaces, and can be referenced by the MOV instruction.
Accordingly, all addressing modes can be used to access data, enabling efficient programming.
The address space differs according to the two memory modes of memory extension mode and processor mode.
For details on the address space in each memory mode, refer to Fig. 4-3-1 and Fig. 4-3-2. When using the register
indirect with displacement and register indirect with index addressing modes, make sure that the space (either the
internal instruction space, the internal data space, the internal I/O space, or the external memory space) containing
the address pointed at by the base registers (Am, An and SP) and the space containing the calculated address are the
same.