Instructions
M25PX16
6.2
Write Disable (WRDI)
The Write Disable (WRDI) instruction (Figure 9) resets the Write Enable Latch (WEL) bit.
The Write Disable (WRDI) instruction is entered by driving Chip Select (S) Low, sending the
instruction code, and then driving Chip Select (S) High.
The Write Enable Latch (WEL) bit is reset under the following conditions:
Power-up
Write Disable (WRDI) instruction completion
Write Status Register (WRSR) instruction completion
Write lo Lock Register (WRLR) instruction completion
Page Program (PP) instruction completion
Dual Input Fast Program (DIFP) instruction completion
Program OTP (POTP) instruction completion
Subsector Erase (SSE) instruction completion
Sector Erase (SE) instruction completion
Bulk Erase (BE) instruction completion
Figure 9.
Write Disable (WRDI) instruction sequence
S
0
1
2
3
4
5
6
7
C
Instruction
DQ0
DQ1
High Impedance
AI13732
6.3
Read Identification (RDID)
The Read Identification (RDID) instruction allows to read the device identification data:
Manufacturer identification (1 byte)
Device identification (2 bytes)
A Unique ID code (UID) (17 bytes, of which 16 available upon customer request).
The manufacturer identification is assigned by JEDEC, and has the value 20h. The device
identification is assigned by the device manufacturer, and indicates the memory type in the
first byte (71h), and the memory capacity of the device in the second byte (15h). The UID
contains the length of the following data in the first byte (set to 10h) and 16 bytes of the
optional Customized Factory Data (CFD) content. The CFD bytes are read-only and can be
programmed with customers data upon their demand. If the customers do not make
requests, the devices are shipped with all the CFD bytes programmed to zero (00h).
24/65