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SH7751 Group, SH7751R Group
Section 13 Bus State Controller (BSC)
R01UH0457EJ0301 Rev. 3.01
Page 351 of 1128
Sep 24, 2013
Bit 20—Area 4 SRAM Byte Control Mode (A4MBC):
MPX interface has priority when an
MPX interface is set. This bit is initialized by a power-on reset.
Bit 20: A4MBC
Description
0
Area 4 SRAM is set to normal mode
(Initial value)
1
Area 4 SRAM is set to byte control mode
Bit 19—BREQ Enable (BREQEN):
Indicates whether external requests and bus requests from
PCIC can be accepted. BREQEN is initialized to the external request and bus request from PCIC
acceptance disabled state by a power-on reset. It is ignored in the case of a slave mode startup.
The bus request from the PCIC is always accepted in a slave mode start up.
Bit 19: BREQEN
Description
0
External requests and bus requests from PCIC are not accepted
(Initial
value)
1
External requests and bus requests from PCIC are accepted
Bit 17—Area 1 to 6 MPX Bus Specification (MEMMPX):
Sets the MPX interface when areas 1
to 6 are set as SRAM interface (or burst ROM interface). MEMMPX is initialized by a power-on
reset.
Bit 17: MEMMPX
Description
0
SRAM interface (or burst ROM interface) is selected when areas 1 to 6 are
set as SRAM interface (or burst ROM interface)
(Initial value)
1
MPX interface is selected when areas 1 to 6 are set as SRAM interface (or
burst ROM interface)
Bit 16—DMAC Burst Mode Transfer Priority Setting (DMABST):
Specifies the priority of
burst mode transfers by the DMAC. When OFF, the priority is as follows: bus privilege released,
refresh, DMAC, CPU. When ON, the bus privileges are released and refresh operations are not
performed until the end of the DMAC's burst transfer. This bit is initialized at a power-on reset.
Bit 16: DMABST
Description
0
DMAC burst mode transfer priority specification OFF
(Initial value)
1
DMAC burst mode transfer priority specification ON