Datasheet

Section 3 MCU Operating Modes
Rev. 3.00 Sep. 28, 2009 Page 68 of 910
REJ09B0350-0300
3.2 Register Descriptions
The following registers are related to the operating modes.
Table 3.2 Register Configuration
Register Name Abbreviation R/W Initial Value Address
Data Bus
Width
Mode control register MDCR R/W ⎯ H'FFC5 8
System control register SYSCR R/W H'09 H'FFC4 8
Serial timer control register STCR R/W H'00 H'FFC3 8
System control register 3 SYSCR3 R/W H'60 H'FE7D 8
3.2.1 Mode Control Register (MDCR)
MDCR is used to set an operating mode and to monitor the current operating mode.
Bit Bit Name
Initial
Value
R/W Description
7 EXPE 0 R/W Reserved
The initial value should not be changed.
6 to 3 — All 0 R Reserved
The initial value should not be changed.
2
1
MDS2
MDS1
—*
—*
R
R
Mode Select 2 and 1
These bits indicate the input levels at mode pins (MD2
and MD1) (the current operating mode). The MDS2 and
MDS1 bits correspond to the MD2 and MD1 pins,
respectively. These bits are read-only bits and cannot
be written to.
The input levels of the mode pins (MD2 and MD1) are
latched into these bits when MDCR is read. These
latches are canceled by a reset.
0 — 0 R Reserved
The initial value should not be changed.
Note: * The initial values are determined by the settings of the MD2 and MD1 pins.