ACE25C320G Datasheet, PDF (27/37 Pages) ACE Technology Co., LTD. – Uniform SECTOR Dual and Quad Serial Flash

ACE25C320G
Uniform SECTOR Dual and Quad Serial Flash
Figure 25. Erase Security Registers command Sequence Diagram
Program Security Registers (42H)
The Program Security Registers command is similar to the Page Program command. It allows from
1 to 256 bytes Security Registers data to be programmed. A Write Enable (WREN) command must
previously have been executed to set the Write Enable Latch (WEL) bit before sending the Program
Security Registers command. The Program Security Registers command is entered by driving CS#
Low, followed by the command code (42H), three address bytes and at least one data byte on SI. As
soon as CS# is driven high, the self-timed Program Security Registers cycle (whose duration is tPP)
is initiated. While the Program Security Registers cycle is in progress, the Status Register may be
read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1 during
the self-timed Program Security Registers cycle, and is 0 when it is completed. At some unspecified
time before the cycle is completed, the Write Enable Latch (WEL) bit is reset.
If the Security Registers Lock Bit (LB3/LB2/LB1) is set to 1, the Security Registers will be
permanently locked. Program Security Registers command will be ignored.
Address
A23-A16
A15-A8
A7-A0
Security Registers 1
00H
01H
Byte Address
Security Registers 2
00H
02H
Byte Address
Security Registers 3
00H
03H
Byte Address
Figure26. Program Security Registers command Sequence Diagram
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