h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 144

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 7 Bus Controller (BSC)
7.3.1
ABWCR designates each area in the external address space as either 8-bit access space or 16-bit
access space.
7.3.2
ASTCR designates each area in the external address space as either 2-state access space or 3-state
access space.
Rev. 2.00 Dec. 05, 2005 Page 106 of 724
REJ09B0200-0200
Bit
7
6
5
4
3
2
1
0
Bit
7
6
5
4
3
2
1
0
Bit Name
ABW7
ABW6
ABW5
ABW4
ABW3
ABW2
ABW1
ABW0
Bit Name
AST7
AST6
AST5
AST4
AST3
AST2
AST1
AST0
Bus Width Control Register (ABWCR)
Access State Control Register (ASTCR)
Initial
Value
1/0
1/0
1/0
1/0
1/0
1/0
1/0
1/0
Initial
Value
1
1
1
1
1
1
1
1
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Description
Area 7 to 0 Bus Width Control
These bits select whether the corresponding area is to
be designated as 8-bit access space or 16-bit access
space.
0: Area n is designated as 16-bit access space
1: Area n is designated as 8-bit access space
Description
Area 7 to 0 Access State Control
These bits select whether the corresponding area is to
be designated as 2-state access space or 3-state
access space. Wait state insertion is enabled or
disabled at the same time.
0: Area n is designated as 2-state access space
1: Area n is designated as 3-state access space
Wait state insertion in area n access is disabled
Wait state insertion in area n access is enabled
(n = 7 to 0)
(n = 7 to 0)