beautypg.com

8 break bus cycle register b (bbrb) – Renesas SH7641 User Manual

Page 299

background image

Section 11 User Break Controller (UBC)

Rev. 4.00 Sep. 14, 2005 Page 249 of 982

REJ09B0023-0400

11.2.8 Break

Bus

Cycle Register B (BBRB)

Break bus cycle register B (BBRB) is a 16-bit readable/writable register, which specifies (1) X bus
or Y bus, (2) L bus cycle or I bus cycle, (3) instruction fetch or data access, (4) read or write,
and (5) operand size in the break conditions of channel B.

Bit Bit

Name

Initial
Value R/W Description

15 to 10

 All

0

R

Reserved

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

9

XYE

0

R/W

Selects the X memory bus or Y memory bus as the
channel B break condition. Note that this bit setting is
enabled only when the L bus is selected with the CDB1
and CDB0 bits. Selection between the X memory bus
and Y memory bus is done by the XYS bit.

0: Selects L bus for the channel B break condition

unconditionally

1: Selects X/Y memory bus for the channel B break

condition

8

XYS

0

R/W

Selects the X bus or the Y bus as the bus of the
channel B break condition.

0: Selects the X bus for the channel B break condition

1: Selects the Y bus for the channel B break condition

7

6

CDB1

CDB0

0

0

R/W

R/W

L Bus Cycle/I Bus Cycle Select B

Select the L bus cycle or I bus cycle as the bus cycle
of the channel B break condition.

00: Condition comparison is not performed

01: The break condition is the L bus cycle

10: The break condition is the I bus cycle

11: The break condition is the L bus cycle

This manual is related to the following products: