SH7708 datasheet(154/633 Pages) RENESAS

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7.3.3

Data Access Cycle Break

1. In the case of a data access cycle break, the bits used for comparison with the address bus

depend on the break bus cycle register (BBRA/BBRB) operand size specification, as follows:

Operand size

Compared address

Not included in conditions (00):

For byte address, comparison with address bits A31–A0

For word address, comparison with address bits A31–A1

For longword address, comparison with address bits

A31–A2

Byte (01):

Comparison with address bits A31–A0

Word (10):

Comparison with address bits A31–A1

Longword (11):

Comparison with address bits A31–A2

2. When data value is included in break condition in channel B

When the data value is included in the break conditions, set the DBEB bit in the break control

B (BDMRB) settings are needed in addition to the address condition. A user break trap is

generated on a match of the address condition and the data condition.

Bits IDB1 and IDB0 of break bus cycle register B (BBRB) should be set to 00 or 01.

When byte data is specified, set the same data in the two bytes comprising bits 15–8 and bits

7–0 in break data register B (BDRB) and break mask register B (BDMRB). If word or byte is

designated, bits 31–16 of BDRB and BDMRB are ignored.

SH7708 Datasheet(PDF) 154 Page - Renesas Technology Corp