W25Q256FVBIF-TR Datasheet, PDF (38/108 Pages) Winbond – 3V 256M-BIT SERIAL FLASH MEMORY WITH DUAL/QUAD SPI & QPI

W25Q256FV
8.2.7 Write Extended Address Register (C5h)
The Extended Address Register is a volatile register that stores the 4^th byte address (A31-A24) when the
device is operating in the 3-Byte Address Mode (ADS=0). To write the Extended Address Register bits, a
Write Enable (06h) instruction must previously have been executed for the device to accept the Write
Extended Address Register instruction (Status Register bit WEL must equal 1). Once write enabled, the
instruction is entered by driving /CS low, sending the instruction code “C5h”, and then writing the
Extended Address Register data byte as illustrated in Figure 11.
Upon power up or the execution of a Software/Hardware Reset, the Extended Address Register bit
values will be cleared to 0.
The Extended Address Register is only effective when the device is in the 3-Byte Address Mode. When
the device operates in the 4-Byte Address Mode (ADS=1), any command with address input of A31-A24
will replace the Extended Address Register values. It is recommended to check and update the Extended
Address Register if necessary when the device is switched from 4-Byte to 3-Byte Address Mode.
/CS
CLK
DI
(IO₀)
DO
(IO₁)
Mode 3
0
Mode 0
* ^{= MSB}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Instruction (C5h)
Ext. Add. Reg in
76543210
*
High Impedance
Mode 3
Mode 0
Figure 11a. Write Extended Address Register Instruction (SPI Mode)
/CS
CLK
IO₀
Mode 3
Mode 0
0123
Instruction _{Ext Add}
C5h
Reg. in
40
Mode 3
Mode 0
IO₁
51
IO₂
62
IO₃
73
Figure 11b. Write Extended Address Register Instruction (QPI Mode)
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