at45db081d-su-sl955 ATMEL Corporation, at45db081d-su-sl955 Datasheet - Page 25

• Manufacturer Part Number: at45db081d-su-sl955
• Description: 8-megabit 2.5-volt Or 2.7-volt Dataflash
• Manufacturer: ATMEL Corporation

13. “Power of 2” Binary Page Size Option
13.1
3596I–DFLASH–4/08
Programming the Configuration Register
“Power of 2” binary page size Configuration Register is a user-programmable nonvolatile regis-
ter that allows the page size of the main memory to be configured for binary page size
(256 bytes) or DataFlash standard page size (264 bytes). The “power of 2” page size is a one-
time programmable configuration register and once the device is configured for “power
of 2” page size, it cannot be reconfigured again. The devices are initially shipped
with the page size set to 264 bytes. The user has the option of ordering binary page size (256
bytes) devices from the factory. For details, please refer to
page
For the binary “power of 2” page size to become effective, the following steps must be followed:
If the above steps are not followed in setting the the page size prior to page programming, user
may expect incorrect data during a read operation.
The address format will be changed after the device is configured for “power of 2” page size.
See
(Except Status Register Read, Manufacturer and Device ID Read)” on page
To program the Configuration Register for “power of 2” binary page size, the CS pin must first be
asserted as it would be with any other command. Once the CS pin has been asserted, the
appropriate 4-byte opcode sequence must be clocked into the device in the correct order. The
4-byte opcode sequence must start with 3DH and be followed by 2AH, 80H, and A6H. After the
last bit of the opcode sequence has been clocked in, the CS pin must be deasserted to initiate
the internally self-timed program cycle. The programming of the Configuration Register should
take place in a time of t
busy. The device must be power-cycled after the completion of the program cycle to set the
“power of 2” page size. If the device is powered-down before the completion of the program
cycle, then setting the Configuration Register cannot be guaranteed. However, the user should
check bit 0 of the status register to see whether the page size was configured for binary page
size. If not, the command can be re-issued again.
Figure 13-1. Program Configuration Register
Command
Power of Two Page Size
1. Program the one-time programmable configuration resister using opcode sequence
2. Power cycle the device (i.e. power down and power up again).
3. User can now program the page for the binary page size.
Section 21.7 ”Command Sequence for Read/Write Operations for Page Size 256 Bytes
47.
3DH, 2AH, 80H and A6H (please see
CS
SI
P
Each transition
represents 8 bits
, during which time the Status Register will indicate that the device is
Opcode
Byte 1
Opcode
Byte 2
Section
Byte 1
13.1).
3DH
Opcode
Byte 3
Section 26. ”Ordering Information” on
Opcode
Byte 4
Byte 2
2AH
AT45DB081D
Byte 3
80H
38.
Byte 4
A6H
25