Memory Modes
4-4
4.3 Description of Memory Mode
4.3.1 Memory Extension Mode
The memory mode which comprises a system from both internal and external memory is called memory extension
mode. This mode enables configuration of a system where the program and data make the best use of the high-
speed performance of internal memory and the large capacity of external memory. This mode is useful when the
program sizes exceed the maximum internal capacity or when locating instructions externally due to facilitate
program revisions.
Memory extension mode has memory space of up to 3 GB from addresses x'00000000 to x'BFFFFFFF. Addresses
x'00000000 to x'1FFFFFFF are the internal data space (up to 512 MB) which contains data, addresses x'20000000
to x'3FFFFFFF are the internal I/O space (up to 512 MB) which is assigned to the I/O ports and control registers,
addresses x'40000000 to x'7FFFFFFF are the internal instruction space which contains instructions and table data,
and addresses x'80000000 to x'BFFFFFFF are the external memory space (up to 1 GB).
The MN103001G has 128 Kbytes of internal instruction ROM located at x'40000000 to x'4001FFFF. The
MN103001G also has 8 Kbytes of internal data RAM located at x'00000000 to x'00001FFF.
The MN1030F01K has 256 Kbytes of internal flash memory located at x'40000000 to x'4002FFFF. The
MN1030F01K also has 8 Kbytes of internal data RAM located at x'00000000 to x'00001FFF.
Note that it is prohibited to access unmounted space of the internal data space, the internal I/O space and the
internal instruction space. When accessing the unmounted space, the operation is not assured.
Fig. 4-3-1 Memory Space in Extension Memory Mode
System reserve
region
4 GB
Internal data
memory (~512 MB)
Internal I/O
(~512 MB)
Internal instruction
memory (~1 GB)
x'00000000
x'20000000
x'80000000
x'FFFFFFFF
x'BFFFFFFF
x'40000000
External memory
(~1 GB)