Rainbow Electronics AT25DQ321 - Manual (Page 23)

23 AT25DQ321 [DATASHEET]
8718D–DFLASH–12/2012
8.7 Program/Erase Resume
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. 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 a Program/Erase Resume, the CS pin must first be asserted and the opcode of D0h 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 be resumed within a time of
t
RES
. The PS bit or the ES bit in the Status Register will then be reset back to the Logical 0 state to indicate that 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 be performed.
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 t
RES
time before issuing the Program/Erase Suspend command, or it must
check the status of the RDY/BSY bit or the appropriate PS or ES bit in the Status Register to determine if the previously
suspended program or erase operation has resumed.
Figure 8-10. Program/Erase Resume
SO
SI
SCK
CS
MSB
2 3 1 0
1 1 0 1 0 0 0 0
6 7 5 4
Opcode
High-impedance