W25Q256JVEIQ-TR Datasheet, PDF (13/92 Pages) Winbond – 3V 256M-BIT SERIAL FLASH MEMORY WITH DUAL/QUAD SPI

W25Q256JV
6.1.4 3-Byte / 4-Byte Address Modes
The W25Q256JV provides two Address Modes that can be used to specify any byte of data in the memory
array. The 3-Byte Address Mode is backward compatible to older generations of serial flash memory that
only support up to 128M-bit data. To address the 256M-bit or more data in 3-Byte Address Mode,
Extended Address Register must be used in addition to the 3-Byte addresses.
4-Byte Address Mode is designed to support Serial Flash Memory devices from 256M-bit to 32G-bit. The
extended Address Register is not necessary when the 4-Byte Address Mode is enabled.
Upon power up, the W25Q256JV can operate in either 3-Byte Address Mode or 4-Byte Address Mode,
depending on the Non-Volatile Status Register Bit ADP (S17) setting. If ADP=0, the device will operate in
3-Byte Address Mode; if ADP=1, the device will operate in 4-Byte Address Mode. The factory default value
for ADP is 0.
To switch between the 3-Byte or 4-Byte Address Modes, “Enter 4-Byte Mode (B7h)” or “Exit 4-Byte Mode
(E9h)” instructions must be used. The current address mode is indicated by the Status Register Bit ADS
(S16).
W25Q256JV also supports a set of basic SPI instructions which requires dedicated 4-Byte address
regardless the device Address Mode setting. Please refer to Instruction Set Table 2 for details.
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Publication Release Date: September 20, 2016
Revision B