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MX66U51235F Datasheet, PDF (34/96 Pages) Macronix International – 1.8V 512M-BIT [x 1/x 2/x 4] CMOS MXSMIO (SERIAL MULTI I/O) FLASH MEMORY
MX66U51235F
Status Register
The definition of the status register bits is as below:
WIP bit. The Write in Progress (WIP) bit, a volatile bit, indicates whether the device is busy in program/erase/write
status register progress. When WIP bit sets to 1, which means the device is busy in program/erase/write status
register progress. When WIP bit sets to 0, which means the device is not in progress of program/erase/write status
register cycle.
WEL bit. The Write Enable Latch (WEL) bit, a volatile bit, indicates whether the device is set to internal write enable
latch. When WEL bit sets to 1, which means the internal write enable latch is set, the device can accept program/
erase/write status register instruction. When WEL bit sets to 0, which means no internal write enable latch; the
device will not accept program/erase/write status register instruction. The program/erase command will be ignored
if it is applied to a protected memory area. To ensure both WIP bit & WEL bit are both set to 0 and available for next
program/erase/operations, WIP bit needs to be confirm to be 0 before polling WEL bit. After WIP bit confirmed, WEL
bit needs to be confirm to be 0.
BP3, BP2, BP1, BP0 bits. The Block Protect (BP3, BP2, BP1, BP0) bits, non-volatile bits, indicate the protected area
(as defined in Table 2) of the device to against the program/erase instruction without hardware protection mode being
set. To write the Block Protect (BP3, BP2, BP1, BP0) bits requires the Write Status Register (WRSR) instruction to
be executed. Those bits define the protected area of the memory to against Page Program (PP), Sector Erase (SE),
Block Erase 32KB (BE32K), Block Erase (BE) and Chip Erase (CE) instructions (only if Block Protect bits (BP3:BP0)
set to 0, the CE instruction can be executed). The BP3, BP2, BP1, BP0 bits are "0" as default. Which is un-protected.
QE bit. The Quad Enable (QE) bit, non-volatile bit, while it is "0" (factory default), it performs non-Quad and WP#,
RESET# are enable. While QE is "1", it performs Quad I/O mode and WP#, RESET# are disabled. In the other
word, if the system goes into four I/O mode (QE=1), the feature of HPM and RESET will be disabled.
SRWD bit. The Status Register Write Disable (SRWD) bit, non-volatile bit, is operated together with Write Protection
(WP#/SIO2) pin for providing hardware protection mode. The hardware protection mode requires SRWD sets to 1 and
WP#/SIO2 pin signal is low stage. In the hardware protection mode, the Write Status Register (WRSR) instruction is
no longer accepted for execution and the SRWD bit and Block Protect bits (BP3, BP2, BP1, BP0) are read only. The
SRWD bit defaults to be "0".
Status Register
bit7
SRWD (status
register write
protect)
bit6
QE
(Quad
Enable)
bit5
BP3
(level of
protected
block)
bit4
BP2
(level of
protected
block)
1=status
register write
disable
1=Quad
Enable
0=not Quad
Enable
(note 1)
(note 1)
Non-volatile Non-volatile Non-volatile Non-volatile
bit
bit
bit
bit
Note 1: see the Table 2 "Protected Area Size".
bit3
BP1
(level of
protected
block)
(note 1)
Non-volatile
bit
bit2
BP0
(level of
protected
block)
(note 1)
Non-volatile
bit
bit1
bit0
WEL
WIP
(write enable (write in
latch) progress bit)
1=write
enable
0=not write
enable
1=write
operation
0=not in write
operation
volatile bit volatile bit
P/N: PM1863
REV. 1.0, NOV. 28, 2013
34