Bit 4—Strobe Mode Select (CAS/
WE
): Selects 2
CAS
or 2
WE
mode. The setting of this bit is
valid when PSRAME = 0 and DRAME = 1. This bit is write-disabled when the PSRAME or
DRAME bit is set to 1.
Bit 4
CAS/
WE
Description
0
2
WE
mode
(Initial value)
1
2
CAS
mode
Bit 3—Address Multiplex Mode Select (M9/M8): Selects 8-bit or 9-bit column addressing.
The setting of this bit is valid when PSRAME = 0 and DRAME = 1. This bit is write-disabled
when the PSRAME or DRAME bit is set to 1.
Bit 3
M9/
M8
Description
0
8-bit column address mode
(Initial value)
1
9-bit column address mode
Bit 2—Refresh Pin Enable (RFSHE): Enables or disables refresh signal output from the
RFSH
pin. This bit is write-disabled when the PSRAME or DRAME bit is set to 1.
Bit 2
RFSHE
Description
0
Refresh signal output at the
RFSH
pin is disabled
(Initial value)
(the
RFSH
pin can be used as a generic input/output port)
1
Refresh signal output at the
RFSH
pin is enabled
Bit 1—Reserved: Read-only bit, always read as 1.
Bit 0—Refresh Cycle Enable (RCYCE): Enables or disables insertion of refresh cycles.
The setting of this bit is valid when PSRAME = 1 or DRAME = 1. When PSRAME = 0 and
DRAME = 0, refresh cycles are not inserted regardless of the setting of this bit.
Bit 0
RCYCE
Description
0
Refresh cycles are disabled
(Initial value)
1
Refresh cycles are enabled for area 3
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