GD25Q64CFJS datasheet(38/74 Pages) GIGADEVICE

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3.3V Uniform Sector

Dual and Quad Serial Flash

GD25Q64C

7.26. Read Identification (RDID) (9FH)

The Read Identification (RDID) command allows the 8-bit manufacturer identification to be read, followed by two bytes of

device identification. The device identification indicates the memory type in the first byte, and the memory capacity of the

device in the second byte. The Read Identification (RDID) command while an Erase or Program cycle is in progress is not

decoded, and has no effect on the cycle that is in progress. The Read Identification (RDID) command should not be issued

while the device is in Deep Power-Down Mode.

The device is first selected by driving CS# low. Then, the 8-bit command code for the command is shifted in. This is followed

by the 24-bit device identification stored in the memory. Each bit is shifted out on the falling edge of Serial Clock. The

command sequence is shown in Figure31. The Read Identification (RDID) command is terminated by driving CS# high at

any time during data output. When CS# is driven high, the device is in the Standby Mode. Once in the Standby Mode, the

device waits to be selected, so that it can receive, decode and execute commands.

Figure 31. Read Identification ID Sequence Diagram

CS#

SCLK

9 10

MSB

18 19 20 21

22 23

26 27 28 29

30 31

Capacity

JDID7-JDID0

CS#

SCLK

MSB

Memory Type

JDID15-JDID8

11 12 13 14 15

9FH

Manufacturer ID

MSB

Command

GD25Q64CFJS Datasheet(PDF) 38 Page - GigaDevice Semiconductor (Beijing) Inc.