h8s-2635 Renesas Electronics Corporation., h8s-2635 Datasheet - Page 213

• Manufacturer Part Number: h8s-2635
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

7.2.2
ASTCR is an 8-bit readable/writable register that designates each area as either a 2-state access
space or a 3-state access space.
ASTCR sets the number of access states for the external memory space. The number of access
states for on-chip memory and internal I/O registers is fixed regardless of the settings in ASTCR.
ASTCR is initialized to H'FF by a reset and in hardware standby mode. It is not initialized in
software standby mode.
Bits 7 to 0—Area 7 to 0 Access State Control (AST7 to AST0): These bits select whether the
corresponding area is to be designated as a 2-state access space or a 3-state access space.
Wait state insertion is enabled or disabled at the same time.
Bit n
ASTn
0
1
Access State Control Register (ASTCR)
Description
Area n is designated for 2-state access
Wait state insertion in area n external space is disabled
Area n is designated for 3-state access
Wait state insertion in area n external space is enabled
Rev. 6.00 Feb 22, 2005 page 153 of 1484
Section 7 Bus Controller
REJ09B0103-0600
(Initial value)
(n = 7 to 0)