GD25Q64 datasheet(16/50 Pages) ELM

16 / 50 page

Rev.1.1

50 -

http://www.elm-tech.com

GD25Q64CxIGx 3.3V Uniform Sector Dual and Quad Serial Flash

Figure 4. Write Enable for Volatile Status Register Sequence Diagram

CS#

SCLK

Command(50H)

0 1 2 3 4 5 6 7

High-Z

7.5. Write Status Register (WRSR) (01H or 31H or 11H)

The Write Status Register (WRSR) command allows new values to be written to the Status Register. Before it

can be accepted, a Write Enable (WREN) command must previously have been executed. After the Write Enable

(WREN) command has been decoded and executed, the device sets the Write Enable Latch (WEL).

The Write Status Register (WRSR) command has no effect on S23, S20, S19, S18, S17, S16, S15, S10, S1

and S0 of the Status Register. CS# must be driven high after the eighth of the data byte has been latched in.

If not, the Write Status Register (WRSR) command is not executed. As soon as CS# is driven high, the self-

timed Write Status Register cycle (whose duration is tW) is initiated. While the Write Status Register cycle is in

progress, the Status Register may still 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 Write Status Register cycle, and is 0 when it is completed. When

the cycle is completed, the Write Enable Latch (WEL) is reset.

The Write Status Register (WRSR) command allows the user to change the values of the Block Protect (BP4,

BP3, BP2, BP1 and BP0) bits, to define the size of the area that is to be treated as read-only, as defined in

Table1. The Write Status Register (WRSR) command also allows the user to set or reset the Status Register

Figure 5. Read Status Register Sequence Diagram

7.4. Read Status Register (RDSR) (05H or 35H or 15H)

The Read Status Register (RDSR) command is for reading the Status Register. The Status Register may be read

at any time, even while a Program, Erase or Write Status Register cycle is in progress. When one of these cycles

is in progress, it is recommended to check the Write In Progress (WIP) bit before sending a new command to

the device. It is also possible to read the Status Register continuously. For command code “05H”“35H”“15H”,

the SO will output Status Register bits S7~S0 / S15~S8 / S16~S23.

GD25Q64 Datasheet(PDF) 16 Page - ELM Electronics