Renesas M16C/60 Series, User Manual

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R01UH0136EJ0210 Rev.2.10 Page 154 of 800
Jul 31, 2012
M16C/64A Group 12. Memory Space Expansion Function
12. Memory Space Expansion Function
12.1 Introduction
The following describes the memory space expansion function. In memory expansion or microprocessor
mode, the memory space expansion function allows the access space to be expanded. Table 12.1 lists
Memory Space Expansion Function Specifications. In this chapter, the external area accessed by the
CSi
(i = 0 to 3) signal is referred to as the
CSi
area.
12.2 Registers
Table 12.2 lists registers related to the memory expansion function. Refer to 10. “Processor Mode” for the
PM1 register.
Table 12.1 Memory Space Expansion Function Specifications
Item Specification
1-MB mode
•
Memory space 1 MB (no expansion)
•
Specify the external area (
CSi
area) accessed by the
CSi
signal.
4-MB mode
•
Memory space 4 MB
•
Select bank numbers to access to data.
•
Allows the accessed address to be offset by 40000h
•
The
CSi
pin function differs depending on the area to be accessed.
i = 0 to 3
Table 12.2 Registers
Address Register Symbol Reset Value
0005h Processor Mode Register 1 PM1 0000 1000b
000Bh Data Bank Register DBR 00h