n25q256 Numonyx, n25q256 Datasheet - Page 38

• 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

Volatile and Non Volatile Registers
6.1
6.1.1
6.1.2
6.1.3
6.1.4
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Legacy SPI Status Register
The Status Register contains a number of status and control bits that can be read or set by
specific instructions: Read Status Register (RDSR) and Write Status Register (WRSR). This
is available in all the 3 protocols (Extended SPI, DIO-SPI, and QIO-SPI).
Table 3.
WIP bit
The Write In Progress (WIP) bit set to 1 indicates that the memory is busy with a Write
Status Register, Program or Erase cycle. 0 indicates no cycle is in progress.
WEL bit
The Write Enable Latch (WEL) bit set to 1 indicates that the internal Write Enable Latch is
set. When set to 0 the internal Write Enable Latch is reset and no Write Status Register,
Program or Erase instruction is accepted.
BP3, BP2, BP1, BP0 bits
The Block Protect (BP3, BP2, BP1, BP0) bits are non-volatile. They define the size of the
area to be software protected against Program and Erase instructions. These bits are
written with the Write Status Register (WRSR) instruction. When one or more of the Block
Protect (BP3, BP2, BP1, BP0) bits is set to 1, the relevant memory area, as defined in
11.: Protected area sizes, Upper (TB bit = 0)
erase instructions. The Block Protect (BP3, BP2, BP1, BP0) bits can be written provided
that the Hardware Protected mode has not been set. The Bulk Erase (BE) instruction is
executed if, and only if, all Block Protect (BP3, BP2, BP1, BP0) bits are 0.
TB bit
The Top/Bottom (TB) bit is non-volatile. It can be set and reset with the Write Status Register
(WRSR) instruction provided that the Write Enable (WREN) instruction has been issued.
Status register write protect
SRWD
b7
Status register format
BP3
Top/bottom bit
TB
Micron Technology, Inc., reserves the right to change products or specifications without notice.
BP2
becomes protected against all program and
Block protect bits
BP1
Write enable latch bit
BP0
©2010 Micron Technology, Inc. All rights reserved.
WEL
Write in progress bit
N25Q256 - 3 V
WIP
b0
Table