HD64F2168 Datasheet, PDF (94/874 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer

3.2 Register Descriptions
The following registers are related to the operating mode. For details on the bus control register
(BCR), see section 6.3.1, Bus Control Register (BCR), and for details on bus control register 2
(BCR2), see section 6.3.2, Bus Control Register 2 (BCR2).
• Mode control register (MDCR)
• System control register (SYSCR)
• Serial timer control register (STCR)
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 Extended Mode Enable
Specifies extended mode.
0: Single-chip mode
1: Extended mode
6—
All 0
to
3
R
Reserved
2 MDS2
—*
1 MDS1
—*
0 MDS0
—*
R
Mode Select 2 to 0
R
These bits indicate the input levels at mode pins (MD2,
R
MD1, and MD0) (the current operating mode). Bits
MDS2, MDS1, and MDS0 correspond to MD2, MD1,
and MD0, respectively. MDS2 to MDS0 are read-only
bits and they cannot be written to. The mode pin (MD2,
MD1, and MD0) input levels are latched into these bits
when MDCR is read. These latches are canceled by a
reset.
Note: * The initial values are determined by the settings of the MD2, MD1, and MD0 pins.
Rev. 3.00, 03/04, page 54 of 830