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2 bus control register (bcr) – Renesas SH7781 User Manual

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11. Local Bus State Controller (LBSC)

Rev.1.00 Jan. 10, 2008 Page 367 of 1658

REJ09B0261-0100

11.4.2

Bus Control Register (BCR)

BCR is a 32-bit readable/writable register that specifies the function, bus cycle state, etc for each
area. BCR is initialized to H'0000 0000 in big endian mode and to H'8000 0000 in little endian
mode by a power-on reset, however, not initialized by a manual reset.

16

17

18

19

20

21

22

23

24

25

26

27

28

29

31

30

0

0

0

0

0

0

0

0

0

0

0

0

0

0

x*

x*

DMA

BST

BREQ

EN

DACKBST[3:0]

OPUP

DPUP

END

IAN

MAS

TER

R/W

R/W

R

R

R/W

R/W

R/W

R/W

R/W

R

R/W

R

R

R

R

R

BIt:

Initial value:

R/W:

0

1

2

3

4

5

6

7

8

9

10

11

12

13

15

14

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

ASYNC[6:0]

HIZ

CNT

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R

R

R

R

R

R

R

R

R/W

BIt:

Initial value:

R/W:

Note: * The initial values of bits 31 and 30 depend on the states of the external pins MODE8 and MODE9, respectively.

Bit Bit

Name

Initial
Value

R/W Description

31 ENDIAN

x

R

Endian

Flag

The value on the external pin (MODE8) that sets the
endian mode is sampled and reflected in this bit at a
power-on reset by the

PRESET pin. This bit determines

the endian for all spaces.

0: Indicates that a low level is on the MODE8 pin at a

power-on reset and the LSI has been configured for
big endian.

1: Indicates that a high level is on the MODE8 pin at a

power-on reset and the LSI has been configured for
little endian.

30 MASTER

x

R

Master/Slave

Flag

The value on the external pin (MODE9) that sets
master/slave is sampled and reflected in this bit at a
power-on reset by the

PRESET pin. This bit specifies

master/slave for all spaces.

0: Indicates that a high level is on the MODE9 and the

LSI has been configured as master.

1: Indicates that a high level is on the MODE9 and the

LSI has been configured as slave.

29 to 27

All 0

R

Reserved

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