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Section 3 MCU Operating Modes
Rev. 3.00 Mar. 14, 2006 Page 68 of 804
REJ09B0104-0300
3.2 Register
Descriptions
The following registers are related to the operating mode setting.
•
Mode control register (MDCR)
•
System control register (SYSCR)
3.2.1
Mode Control Register (MDCR)
MDCR indicates the current operating mode. When MDCR is read, the states of signals input on
pins MD1 and MD0 are latched. The latch is released by a reset.
Bit
Bit Name
Initial Value
R/W
Note:
*
Determined by pins MD1 and MD0.
15
—
0
R
14
—
1
R
13
—
0
R
12
—
1
R
11
MDS3
Undefined
*
R
10
MDS2
Undefined
*
R
9
MDS1
Undefined
*
R
8
MDS0
Undefined
*
R
Bit
Bit Name
Initial Value
R/W
7
—
0
R
6
—
1
R
5
—
0
R
4
—
1
R
3
—
Undefined
*
R
2
—
Undefined
*
R
1
—
Undefined
*
R
0
—
Undefined
*
R
Bit
Bit Name Initial Value R/W Descriptions
15
14
13
12
0
1
0
1
R
R
R
R
Reserved
These are read-only bits and cannot be modified.
11
10
9
8
MDS3
MDS2
MDS1
MDS0
Undefined
*
Undefined
*
Undefined
*
Undefined
*
R
R
R
R
Mode Select 3 to 0
These bits indicate the operating mode selected by the
mode pins (MD1 and MD0) (see table 3.2).
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