Datasheet

Section 3 MCU Operating Modes
Rev.6.00 Mar. 18, 2009 Page 58 of 980
REJ09B0050-0600
3.2 Register Descriptions
The following registers are related to the operating mode.
• Mode control register (MDCR)
• System control register (SYSCR)
3.2.1 Mode Control Register (MDCR)
MDCR monitors the current operating mode of this LSI.
Bit Bit Name Initial Value R/W Descriptions
7 to
3
− All 0 − Reserved
These bits are always read as 0 and cannot be
modified.
2
1
0
MDS2
MDS1
MDS0
−
*
−
*
−
*
R
R
R
Mode Select 2 to 0
These bits indicate the input levels at pins MD2 to
MD0 (the current operating mode). Bits MDS2 to
MDS0 correspond to MD2 to MD0. MDS2 to MDS0
are read-only bits and they cannot be written to. The
mode pin (MD2 to MD0) input levels are latched into
these bits when MDCR is read. These latches are
canceled by a reset.
Note: * Determined by pins MD2 to MD0.
3.2.2 System Control Register (SYSCR)
SYSCR controls CPU access to the flash memory control registers, sets external bus mode, and
enables or disables on-chip RAM.