EN25D16
Write Disable (WRDI) (04h)
The Write Disable instruction (Figure 6) resets the Write Enable Latch (WEL) bit in the Status
Register to a 0 or exit from OTP mode to normal mode. The Write Disable instruction is entered by
driving Chip Select (CS#) low, shifting the instruction code “04h” into the DI pin and then driving Chip
Select (CS#) high. Note that the WEL bit is automatically reset after Power-up and upon completion
of the Write Status Register, Page Program, Sector Erase, Block Erase (BE) and Chip Erase
instructions.
Figure 6. Write Disable Instruction Sequence Diagram
Read Status Register (RDSR) (05h)
The Read Status Register (RDSR) instruction allows the Status Register to be read. 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 instruction to the device. It is also possible to read the Status Register continuously,
as shown in Figure 7.
Figure 7. Read Status Register Instruction Sequence Diagram
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
12
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
Rev. B, Issue Date: 2008/06/23
EON [ EON SILICON SOLUTION INC. ]
