7220 Datasheet, PDF (6/303 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

2. Register diagram
The figure of each register structure describes its functions, contents at reset, end attributes as follows:
CPU Mode Register
b7 b6 b5 b4 b3 b2 b1 b0
11111 00
Bits
Bit attributes (Note 2)
Values immediately after reset release ^{(Note 1)}
CPU mode register (CPUM) (CM) [Address FB 16]
B
Name
0, 1 ^{Fix these bits to “0.”}
Functions
2 ^{Stack page selection 0: 0 page}
bit (CM2)
1: 1 page
3 Fix these bits to “1.”
to
5
6, 7
After reset R W
0
RW
1
RW
1
RW
Indeterminate R W
: Bit in which nothing is assigned
Notes 1: Values immediately after reset release
0••••••“0” after reset release
1••••••“1” after reset release
?••••••Indeterminate after reset release
2: Bit attributes••••••The attributes of control register bits are classified into 3 types : read-only, write-only
and read and write. In the figure, these attributes are represented as follows :
R••••••Read
R ••••••Read enabled
— ••••••Read disabled
W••••••Write
W ••••••Write enabled
— ••••••Write disabled
V ••••••“0” can be set by software, but “1”
cannot be set.
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