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6.2.5
Bus Control Register L (BCRL)
7
BRLE
0
R/W
6
—
0
R/W
5
—
0
—
4
—
0
R/W
3
—
1
R/W
0
WAITE
0
R/W
2
—
0
R/W
1
—
0
R/W
Bit
Initial value
R/W
:
BCRL is an 8-bit readable/writable register that performs selection of the external bus-released
state protocol, and enabling or disabling of
WAIT pin input.
BCRL is initialized to H'08 by a power-on reset and in hardware standby mode. It is not initialized
by a manual reset or in software standby mode.
Bit 7—Bus Release Enable (BRLE): Enables or disables external bus release.
Bit 7
BRLE
Description
0
External bus release is disabled.
BREQ and BACK can be used as I/O ports.
(Initial value)
1
External bus release is enabled.
Bit 6—Reserved: Only 0 should be written to this bit.
Bit 5—Reserved: This bit cannot be modified and is always read as 0.
Bit 4—Reserved: Only 0 should be written to this bit.
Bit 3—Reserved: Only 1 should be written to this bit.
Bits 2 and 1—Reserved: Only 0 should be written to these bits.
Bit 0—WAIT Pin Enable (WAITE): Selects enabling or disabling of wait input by the
WAIT
pin.
Bit 0
WAITE
Description
0
Wait input by
WAIT pin disabled. WAIT pin can be used as I/O port.
(Initial value)
1
Wait input by
WAIT pin enabled