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Renesas SH7641 User Manual

Page 353

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Section 12 Bus State Controller (BSC)

Rev. 4.00 Sep. 14, 2005 Page 303 of 982

REJ09B0023-0400

Bit Bit

Name

Initial
Value R/W Description

6 WM 0 R/W

External

Wait

Mask

Specification

Specifies whether or not the external wait input is valid.
The specification by this bit is valid even when the
number of access wait cycle is 0.

0: External wait is valid

1: External wait is ignored

5 to 0

 All

0

R

Reserved

These bits are always read as 0. The write value
should always be 0.

• CS4WCR

Bit Bit

Name

Initial
Value R/W Description

31 to 21

 All

0

R

Reserved

These bits are always read as 0. The write value
should always be 0.

20

BEN

0

R/W

Burst Enable Specification

Enables or disables 8-burst access for a 16-bit bus
width or 16- burst access for an 8-bit bus width during
16-byte access. If this bit is set to 0, 2-burst access is
performed four times when the bus width is 16 bits and
4-burst access is performed four times when the bus
width is 8 bits. To use a device that does not support
8-burst access or 16-burst access, set this bit to 1.

0: Enables 8-burst access for a 16-bit bus width and

16-burst access for an 8-bit bus width.

1: Disables 8-burst access for a 16-bit bus width and

16-burst access for an 8-bit bus width.

19, 18

 All

0

R

Reserved

These bits are always read as 0. The write value
should always be 0.

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