p2125vps20 Renesas Electronics Corporation., p2125vps20 Datasheet - Page 145

• Manufacturer Part Number: p2125vps20
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

6.3
The bus controller has the following registers. For details on the system control register, refer to
section 3.2.2, System Control Register (SYSCR).
• Bus control register (BCR)
• Wait state control register (WSCR)
6.3.1
BCR is used to specify the access mode for the external address space or the I/O area range when
the AS/IOS pin is specified as an I/O strobe pin.
Bit
7
6
5
4
Bit Name
—
ICIS0
BRSTRM
BRSTS1
Register Descriptions
Bus Control Register (BCR)
Initial
Value
1
1
0
1
R/W
R/W
R/W
R/W
R/W
Idle Cycle Insertion
Description
Reserved
The initial value should not be changed.
Selects whether or not to insert 1-state of the idle cycle
between bus cycles when the external write cycle follows
the external read cycle.
0: Idle cycle not inserted when the external write cycle
1: 1-state idle cycle inserted when the external write cycle
Burst ROM Enable
Selects the bus interface for the external address space.
0: Basic bus interface
1: Burst ROM interface
Burst Cycle Select 1
Selects the number of states in the burst cycle of the burst
ROM interface.
0: 1 state
1: 2 states
follows the external read cycle
follows the external read cycle
Rev. 1.00 Sep. 21, 2006 Page 107 of 658
Section 6 Bus Controller (BSC)
REJ09B0310-0100