W25Q80BWSVIP datasheet(38/74 Pages) WINBOND

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W25Q80BW

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7.2.19

Continuous Read Mode Bits (M7-0)

The “Continuous Read Mode” bits are used in conjunction with “Fast Read Dual I/O”, “Fast Read Quad

I/O”, “Word Read Quad I/O” and “Octal Word Read Quad I/O” instructions to provide the highest random

Flash memory access rate with minimum SPI instruction overhead, thus allow true XIP (execute in place)

to be performed on serial flash devices.

M7-0 need to be set by the Dual/Quad I/O Read instructions. M5-4 are used to control whether the 8-bit

SPI instruction code (BBh, EBh, E7h or E3h) is needed or not for the next command. When M5-4 = (1,0),

the next command will be treated same as the current Dual/Quad I/O Read command without needing

the 8-bit instruction code; when M5-4 do not equal to (1,0), the device returns to normal SPI mode, all

commands can be accepted. M7-6 and M3-0 are reserved bits for future use, either 0 or 1 values can be

used.

7.2.20

Continuous Read Mode Reset (FFh or FFFFh)

Continuous Read Mode Reset instruction can be used to set M4 = 1, thus the device will release the

Continuous Read Mode and return to normal SPI operation, as shown in figure 18.

/CS

CLK

Mode 0

Mode 3

Don't Care

Mode Bit Reset

for Quad I/O (FFh)

Mode 0

Mode 3

Mode Bit Reset

for Dual I/O (FFFFh)

Don't Care

Figure 18. Continuous Read Mode Reset for Fast Read Dual/Quad I/O

Since W25Q80BW does not have a hardware Reset pin, so if the controller resets while W25Q80BW is

set to Continuous Mode Read, the W25Q80BW will not recognize any initial standard SPI instructions

from the controller. To address this possibility, it is recommended to issue a Continuous Read Mode

Reset instruction as the first instruction after a system Reset. Doing so will release the device from the

Continuous Read Mode and allow Standard SPI instructions to be recognized.

To reset “Continuous Read Mode” during Quad I/O operation, only eight clocks are needed. The

instruction is “FFh”. To reset “Continuous Read Mode” during Dual I/O operation, sixteen clocks are

needed to shift in instruction “FFFFh”.

W25Q80BWSVIP 데이터시트(PDF) 38 Page - Winbond