SH7706 Datasheet, PDF (227/749 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family/SH7700 Series

Section 8 Bus State Controller (BSC)
Bit
5
4
3 to 0
Bit Name
A2SZ1
A2SZ0
Initial Value R/W
1
R/W
1
R/W
—
All 0
R
Description
Area 2 Bus Size Specification
Specify the bus sizes of physical space area 2.
• When port A/B is unused.
00: Reserved (Setting prohibited)
01: Byte (8-bit) size
10: Word (16-bit) size
11: Longword (32-bit) size
• When port A/B is used.
00: Reserved (Setting prohibited)
01: Byte (8-bit) size
10: Word (16-bit) size
11: Reserved (Setting prohibited)
Reserved
These bits are always read as 0. The write value
should always be 0.
8.4.3 Wait State Control Register 1 (WCR1)
Wait state control register 1 (WCR1) is a 16-bit read/write register that specifies the number of
idle (wait) state cycles inserted for each area. For some memories, the drive of the data bus may
not be turned off quickly even when the read signal from the external device is turned off. This
can result in conflicts between data buses when consecutive memory accesses are to different
memories or when a write immediately follows a memory read. This LSI automatically inserts idle
states equal to the number set in WCR1 in those cases.
WCR1 is initialized to H'3FF3 by a power-on reset. It is not initialized by a manual reset or by
standby mode.
Rev. 5.00 May 29, 2006 page 179 of 698
REJ09B0146-0500