EN25S16 Datasheet, PDF (15/58 Pages) Eon Silicon Solution Inc. – 16 Megabit 1.8V Serial Flash Memory with 4Kbyte Uniform Sector

EN25S16
Enable Quad Peripheral Interface mode (EQPI) (38h)
The Enable Quad Peripheral Interface mode (EQPI) instruction will enable the flash device for Quad
SPI bus operation. Upon completion of the instruction, all instructions thereafter will be 4-bit multiplexed
input/output until a power cycle or “ Reset Quad I/O instruction “ instruction, as shown in Figure 6. The
device did not support the Read Data Bytes (READ) (03h), Dual Output Fast Read (3Bh) and Dual
Input/Output FAST_READ (BBh) modes while the Enable Quad Peripheral Interface mode (EQPI) (38h)
turns on.
Figure 6. Enable Quad Peripheral Interface mode Sequence Diagram
Reset Quad I/O (RSTQIO) or Release Quad I/O Fast Read Enhancement Mode (FFh)
The Reset Quad I/O instruction resets the device to 1-bit Standard SPI operation. To execute a Reset
Quad I/O operation, the host drives CS# low, sends the Reset Quad I/O command cycle (FFh) then,
drives CS# high. This command can’t be used in Standard SPI mode.
User also can use the FFh command to release the Quad I/O Fast Read Enhancement Mode. The
detail description, please see the Quad I/O Fast Read Enhancement Mode section.
Note:
If the system is in the Quad I/O Fast Read Enhance Mode under EQPI Mode, it is necessary to execute
FFh command by two times. The first FFh command is to release Quad I/O Fast Read Enhance Mode,
and the second FFh command is to release EQPI Mode.
Write Enable (WREN) (06h)
The Write Enable (WREN) instruction (Figure 7) sets the Write Enable Latch (WEL) bit. The Write
Enable Latch (WEL) bit must be set prior to every Page Program (PP), Sector Erase (SE), Block Erase
(BE), Chip Erase (CE) and Write Status Register (WRSR) instruction.
The Write Enable (WREN) instruction is entered by driving Chip Select (CS#) Low, sending the
instruction code, and then driving Chip Select (CS#) High.
The instruction sequence is shown in Figure 8.1 while using the Enable Quad Peripheral Interface mode
(EQPI) (38h) command.
This Data Sheet may be revised by subsequent versions
15
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc.,
Rev. H, Issue Date: 2011/12/16
www.eonssi.com