25Q128FVPF datasheet(74/99 Pages) WINBOND

74 / 99 page

W25Q128FV

- 73 -

8.2.36Enter QPI Mode (38h)

The W25Q128FV support both Standard/Dual/Quad Serial Peripheral Interface (SPI) and Quad Peripheral

Interface (QPI). However, SPI mode and QPI mode cannot be used at the same time. “Enter QPI (38h)”

instruction is the only way to switch the device from SPI mode to QPI mode.

Upon power-up, the default state of the device upon is Standard/Dual/Quad SPI mode. This provides full

backward compatibility with earlier generations of Winbond serial flash memories. See Instruction Set

Table 1-3 for all supported SPI commands. In order to switch the device to QPI mode, the Quad Enable

(QE) bit in Status Register-

2 must be set to 1 first, and an “Enter QPI (38h)” instruction must be issued. If

the Quad Enable (QE) bit is 0, the “Enter QPI (38h)” instruction will be ignored and the device will remain

in SPI mode.

See Instruction Set Table 3 for all the commands supported in QPI mode.

When the device is switched from SPI mode to QPI mode, the existing Write Enable and Program/Erase

Suspend status, and the Wrap Length setting will remain unchanged.

/CS

CLK

(IO

Mode 0

Mode 3

Instruction (38h)

High Impedance

Mode 0

Mode 3

Figure 50. Enter QPI Instruction (SPI Mode only)

25Q128FVPF Datasheet(PDF) 74 Page - Winbond