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Renesas SH7781 User Manual

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11. Local Bus State Controller (LBSC)

Rev.1.00 Jan. 10, 2008 Page 374 of 1658
REJ09B0261-0100

Bit Bit

Name

Initial
Value R/W Description

15

⎯ 0

R

Reserved

This bit is always read as 0. The write value should
always be 0.

14 to 12 IWRRS

111

R/W

Idle Cycles between Read-Read in Same Space

These bits specify the number of idle cycles to be
inserted after the memory connected to the space is
accessed. The target cycles are read-read cycles in
which consecutive accesses are performed to the same
space. For details, see section 11.5.8, Wait Cycles
between Access Cycles.

000: No idle cycle inserted

001: 1 idle cycle inserted

010: 2 idle cycles inserted

011: 3 idle cycles inserted

100: 4 idle cycles inserted

101: 5 idle cycles inserted

110: 6 idle cycles inserted

111: 7 idle cycles inserted

11, 10

BST

01

R/W

Burst Number

These bits specify the number of bursts when the burst
ROM interface is used. The MPX interface is not
affected.

00: 4 consecutive accesses (Can be used with 8-, 16-,

or 32-bit bus width)

01: 8 consecutive accesses (Can be used with 8-, 16-,

or 32-bit bus width)

10: 16 consecutive accesses (Can be used with 8-, or

16-bit bus width)

11: 32 consecutive accesses (Can be used with 8-bit

bus width)