Uniform Sector

Standard and Dual Serial Flash

GD25WD40C/20C

18

Figure6. Read Data Bytes at Higher Speed Sequence Diagram

7.7. Dual Output Fast Read (3BH)

The Dual Output Fast Read command is followed by 3-byte address (A23-A0) and a dummy byte, and each bit being

latched in on the rising edge of SCLK, then the memory contents are shifted out 2-bit per clock cycle from SI and SO.

The command sequence is shown in followed Figure7. The first byte addressed can be at any location. The address is

automatically incremented to the next higher address after each byte of data is shifted out.

Figure7. Dual Output Fast Read Sequence Diagram

7.8. Page Program (PP) (02H)

The Page Program (PP) command is for programming the memory. A Write Enable (WREN) command must

previously have been executed to set the Write Enable Latch (WEL) bit before sending the Page Program command.

Command

0

1

2

3

4

5

6

7

0BH

CS#

SCLK

SI

SO

High-Z

8

9 10

28 29 30 31

3

2

1

0

23 22 21

24-bit address

MSB

34 35 36 37

33

6

5

4

3

2

1

0

38 39

Data Out1

32

42 43 44 45

41

46 47

40

7

6

5

4

3

2

1

0

7

6

5

7

Data Out2

CS#

SCLK

SI

SO

MSB

Dummy Byte

Command

0

1

2

3

4

5

6

7

3BH

CS#

SCLK

SI

SO

High-Z

8

9 10

28 29 30 31

3

2

1

0

23 22 21

24-bit address

MSB

34 35 36 37

33

5

3

1

7

5

3

1

38 39

Data Out1

32

42 43 44 45

41

46 47

40

7

Data Out2

CS#

SCLK

SI

SO

MSB

Dummy Clocks

4

2

0

6

4

2

0

6

6

7