SH7751 Group, SH7751R Group
Section 20 User Break Controller (UBC)
R01UH0457EJ0301 Rev. 3.01
Page 801 of 1128
Sep 24, 2013
Bits 3, 1, and 0—Break Address Mask A2 to A0 (BAMA2–BAMA0):
These bits specify which
bits of the channel A break address (BAA31–BAA0) set in BARA are to be masked.
Bit 3: BAMA2
Bit 1: BAMA1
Bit 0: BAMA0
Description
0
0
0
All BARA bits are included in break
conditions
1
Lower 10 bits of BARA are masked, and not
included in break conditions
1
0
Lower 12 bits of BARA are masked, and not
included in break conditions
1
All BARA bits are masked, and not included
in break conditions
1
0
0
Lower 16 bits of BARA are masked, and not
included in break conditions
1
Lower 20 bits of BARA are masked, and not
included in break conditions
1
*
Reserved (cannot be set)
Legend:
*
Don't care
20.2.5
Break Bus Cycle Register A (BBRA)
Bit:
15 14 13 12 11 10 9 8
— — — — — — — —
Initial
value:
0 0 0 0 0 0 0 0
R/W:
R R R R R R R R
Bit:
7 6 5 4 3 2 1 0
—
SZA2
IDA1
IDA0
RWA1
RWA0
SZA1
SZA0
Initial
value:
0 0 0 0 0 0 0 0
R/W: R R/W R/W R/W R/W R/W R/W R/W
Break bus cycle register A (BBRA) is a 16-bit readable/writable register that sets three
conditions—(1) instruction access/operand access, (2) read/write, and (3) operand size—from
among the channel A break conditions.
BBRA is initialized to H'0000 by a power-on reset. It retains its value in standby mode.
Bits 15 to 7—Reserved:
These bits are always read as 0, and should only be written with 0.