AT25SF321 datasheet(20/48 Pages) DIALOG

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AT25SF321

DS-25SF321–047F–8/2017

Figure 7-5. Program/Erase Suspend

7.5

Program/Erase Resume (7Ah)

The Program/Erase Resume command allows a suspended program or erase operation to be resumed and continue

programming a Flash page or erasing a Flash memory block where it left off. The Program/Erase Resume instruction will

be accepted by the device only if the SUS bit in the Write Status Register equals 1 and the RDY/BSY bit equals 0. If the

SUS bit equals 0 or the RDY/BSY bit equals to 1, the Program/Erase Resume command will be ignored by the device. As

with the Program/Erase Suspend command, the Write Enable command does not need to be issued prior to the

Program/Erase Resume command being issued. Therefore, the Program/Erase Resume command operates

independently of the state of the WEL bit in the Status Register.

To perform Program/Erase Resume, the CS pin must first be asserted and opcode 7Ah must be clocked into the device.

No address bytes need to be clocked into the device, and any data clocked in after the opcode will be ignored. When the

CS pin is deasserted, the program or erase operation currently suspended will resume within a time of tRES. The SUS bit

in the Status Register will then be reset back to the logical "0" state to indicate the program or erase operation is no

longer suspended. In addition, the RDY/BSY bit in the Status Register will indicate that the device is busy performing a

program or erase operation. The complete opcode must be clocked into the device before the CS pin is deasserted, and

the CS pin must be deasserted on a byte boundary (multiples of eight bits). Otherwise, no resume operation will perform.

During a simultaneous Erase Suspend/Program Suspend condition, issuing the Program/Erase Resume command will

result in the program operation resuming first. After the program operation has been completed, the Program/Erase

Resume command must be issued again in order for the erase operation to be resumed.

While the device is busy resuming a program or erase operation, any attempts at issuing the Program/Erase Suspend

command will be ignored. Therefore, if a resumed program or erase operation needs to be subsequently suspended

again, the system must either wait the entire tRES time before issuing the Program/Erase Suspend command, or it must

check the status of the RDY/BSY bit or the SUS bit in the Status Register to determine if the previously suspended

program or erase operation has resumed.

Figure 7-6. Program/Erase Resume.

SCK

MSB

110 1

0 1

OPCODE

GH-

MPEDANCE

SCK

MSB

11 1010

OPCODE

GH-

MPEDANCE

AT25SF321 Datasheet(PDF) 20 Page - Dialog Semiconductor