7 Write Sequence

In order to program the AT25080B/AT25160B/AT25320B/AT25640B, two separate instructions must be executed. First, the device must be write enabled via the Write Enable (WREN) instruction. Then, one of the two possible write sequences described in this section may be executed.

Note: If the device is not Write Enabled (WREN), the device will ignore the WRITE instruction and will return to the standby state when CS is brought high. A new CS assertion is required to re‑initiate communication.

The address of the memory location(s) to be programmed must be outside the protected address field location selected by the block write protection level. During an internal write cycle, all commands will be ignored except the RDSR instruction. Refer to Table 7-1 for the address bits for AT25080B/AT25160B/AT25320B/AT25640B.

Table 7-1. AT25080B/AT25160B/AT25320B/AT25640B Address Bits
Address	AT25080B	AT25160B	AT25320B	AT25640B
A_N	A₉-A₀	A₁₀-A₀	A₁₁-A₀	A₁₂-A₀
Don’t Care Bits	A₁₅-A₁₀	A₁₅-A₁₁	A₁₅-A₁₂	A₁₅-A₁₃