S-25CM01A Datasheet, PDF (13/28 Pages) Seiko Instruments Inc – Function to prevent malfunction by monitoring clock pulse

Rev.2.2_02_S
SPI SERIAL E²PROM
S-25CM01A
2. Write enable (WREN)
Before writing data (WRITE and WRSR), be sure to set bit Write Enable Latch (WEL). This instruction is to set bit
WEL. Its operation is below.
After selecting the device by the chip select ( CS ), input the instruction code from serial data input (SI). To set bit WEL,
set the device in the non-select status by CS at the 8th clock of the serial clock (SCK). To cancel the WREN
instruction, input the clock different from a specified value (n = 8 clocks) while CS is in "L".
CS
WP
High / Low
SCK
SI
SO
1
2
3
4
5
6
7
8
Instruction
High-Z
Figure 10 WREN Operation
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