256Mb: 3V Embedded Parallel NOR Flash
Registers
Registers
Status Register
Table 5: Status Register Bit Definitions
Note 1 applies to entire table
Bit
Name
Settings
Description
Notes
DQ7 Data polling 0 or 1, depending on
Monitors whether the program/erase controller has successful- 2, 3, 4
ly completed its operation, or has responded to an ERASE SUS-
PEND operation.
bit
operations
DQ6 Toggle bit
Toggles: 0 to 1; 1 to 0;
and so on
Monitors whether the program/erase controller has successful- 3, 4, 5
ly completed its operations, or has responded to an ERASE
SUSPEND operation. During a PROGRAM/ERASE operation,
DQ6 toggles from 0 to 1, 1 to 0, and so on, with each succes-
sive READ operation from any address.
DQ5 Error bit
0 = Success
1 = Failure
Identifies errors detected by the program/erase controller. DQ5
is set to 1 when a PROGRAM, BLOCK ERASE, or CHIP ERASE op-
eration fails to write the correct data to the memory.
4, 6
DQ3 Erase timer 0 = Erase not in progress Identifies the start of program/erase controller operation dur-
4
bit
1 = Erase in progress
ing a BLOCK ERASE command. Before the program/erase con-
troller starts, this bit set to 0, and additional blocks to be
erased can be written to the command interface.
DQ2 Alternative Toggles: 0 to 1; 1 to 0;
Monitors the program/erase controller during ERASE opera-
tions. During CHIP ERASE, BLOCK ERASE, and ERASE SUSPEND
operations, DQ2 toggles from 0 to 1, 1 to 0, and so on, with
each successive READ operation from addresses within the
blocks being erased.
3, 4
toggle bit
and so on
DQ1 Buffered
program
1 = Abort
Indicates a BUFFER PROGRAM operation abort. The BUFFERED
PROGRAM ABORT and RESET command must be issued to re-
turn the device to read mode (see WRITE TO BUFFER PRO-
GRAM command).
abort bit
1. The status register can be read during PROGRAM, ERASE, or ERASE SUSPEND operations;
the READ operation outputs data on DQ[7:0].
Notes:
2. For a PROGRAM operation in progress, DQ7 outputs the complement of the bit being
programmed. For a READ operation from the address previously programmed success-
fully, DQ7 outputs existing DQ7 data. For a READ operation from addresses with blocks
to be erased while an ERASE SUSPEND operation is in progress, DQ7 outputs 0; upon
successful completion of the ERASE SUSPEND operation, DQ7 outputs 1. For an ERASE
operation in progress, DQ7 outputs 0; upon either operation's successful completion,
DQ7 outputs 1.
3. After successful completion of a PROGRAM or ERASE operation, the device returns to
read mode.
4. During erase suspend mode, READ operations to addresses within blocks not being
erased output memory array data as if in read mode. A protected block is treated the
same as a block not being erased. See the Toggle Flowchart for more information.
5. During erase suspend mode, DQ6 toggles when addressing a cell within a block being
erased. The toggling stops when the program/erase controller has suspended the ERASE
operation. See the Toggle Flowchart for more information.
PDF: 09005aef84bd3b68
m29w_256mb.pdf - Rev. C 7/13 EN
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