n25q256 Numonyx, n25q256 Datasheet - Page 91

• Manufacturer Part Number: n25q256
• Description: 256-mbit 3 V, Multiple I/o, 4-kbyte Subsector Erase, Xip Enabled, Serial Flash Memory With 108 Mhz Spi Bus Interface
• Manufacturer: Numonyx

N25Q256 - 3 V
9.1.24
Subsector Erase (SSE)
The Subsector Erase (SSE) instruction sets to '1' (FFh) all bits inside the chosen subsector.
Before it can be accepted, a Write Enable (WREN) instruction must previously have been
executed. After the Write Enable (WREN) instruction has been decoded, the device sets the
Write Enable Latch (WEL).
The Subsector Erase (SSE) instruction is entered by driving Chip Select (S) Low, followed
by the instruction code, and three address bytes on Serial Data input (DQ0). Any address
inside the subsector is a valid address for the Subsector Erase (SSE) instruction. Chip
Select (S) must be driven Low for the entire duration of the sequence.
Chip Select (S) must be driven High after the eighth bit of the last address byte has been
latched in, otherwise the Subsector Erase (SSE) instruction is not executed. As soon as
Chip Select (S) is driven High, the self-timed Subsector Erase cycle (whose duration is
tSSE) is initiated. While the Subsector Erase cycle is in progress, the Status Register may
be read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP)
bit is 1 during the self-timed Subsector Erase cycle, and is 0 when it is completed. At some
unspecified time before the cycle is complete, the Write Enable Latch (WEL) bit is reset.
A Subsector Erase (SSE) instruction issued to a sector that is hardware or software
protected, is not executed.
Any Subsector Erase (SSE) instruction, while an Erase, Program or Write cycle is in
progress, is rejected without having any effects on the cycle that is in progress.
If 4-byte address mode is enabled, the device uses a 32-bit address as explained and
shown in
Figure 42. Subsector Erase instruction sequence
S
C
DQ0
Section 5.1.2: 4 Byte Address Mode on page 25
0
1
2
Instruction
3
4
5
6
7
MSB
23 22
Micron Technology, Inc., reserves the right to change products or specifications without notice.
8
9
24 Bit Address
2
29 30 31
1
0
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