ACE25Q400G Datasheet, PDF (33/46 Pages) ACE Technology Co., LTD. – 4M BIT SPI NOR FLASH Memory Series

ACE25Q400G
4M BIT SPI NOR FLASH Memory Series
Program and Erase Instructions
Page Program (02H)
The Page Program instruction is for programming the memory. A Write Enable instruction must
previously have been executed to set the Write Enable Latch bit before sending the Page Program
instruction.
See Figure 25, the Page Program instruction is entered by driving /CS Low, followed by the
instruction code, three address bytes and at least one data byte on SI. If the 8 least significant
address bits (A7-A0) are not all zero, all transmitted data that goes beyond the end of the current
page are programmed from the start address of the same page (from the address whose 8 least
significant bits (A7-A0) are all zero). /CS must be driven low for the entire duration of the sequence.
The Page Program instruction sequence: /CS goes low sending Page Program instruction 3-byte
address on SI at least 1 byte data on SI /CS goes high. The instruction sequence is shown in Figure16.
If more than 256 bytes are sent to the device, previously latched data are discarded and the last 256
data bytes are guaranteed to be programmed correctly within the same page. If less than 256 data
bytes are sent to device, they are correctly programmed at the requested addresses without having
any effects on the other bytes of the same page. /CS must be driven high after the eighth bit of the last
data byte has been latched in; otherwise the Page Program instruction is not executed.
As soon as /CS is driven high, the self-timed Page Program cycle (whose duration is tPP) is
initiated. While the Page Program 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
Page Program cycle, and is 0 when it is completed. At some unspecified time before the cycle is
completed, the Write Enable Latch bit is reset.
A Page Program instruction applied to a page which is protected by the Block Protect (SEC, TB,
BP2, BP1, BP0) bits (see Table 6 & 7) is not executed.
Figure 25 Page Program Sequence Diagram
Figure 25
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