at25p1024 ATMEL Corporation, at25p1024 Datasheet - Page 7

• Manufacturer Part Number: at25p1024
• Description: Spi Serial Eeproms 1m 131,072 X 8
• Manufacturer: ATMEL Corporation

Functional
Description
1082I–SEEPR–7/06
The AT25P1024 is designed to interface directly with the synchronous serial peripheral
interface (SPI) of the 6800 type series of microcontrollers.
The AT25P1024 utilizes an 8-bit instruction register. The list of instructions and their
operation codes are contained in Table 5. All instructions, addresses, and data are
transferred with the MSB first and start with a high-to-low transition.
Table 5. Instruction Set for the AT25P1024
WRITE ENABLE (WREN): The device will power up in the write disable state when V
is applied. All programming instructions must therefore be preceded by a Write Enable
instruction.
WRITE DISABLE (WRDI): To protect the device against inadvertent writes, the Write
Disable instruction disables all programming modes. The WRDI instruction is indepen-
dent of the status of the WP pin.
READ STATUS REGISTER (RDSR): The Read Status Register instruction provides
access to the status register. The Ready/Busy and Write Enable status of the device
can be determined by the RDSR instruction. Similarly, the block write protection bits
indicate the extent of protection employed. These bits are set by using the WRSR
instruction.
Table 6. Status Register Format
Instruction Name
WREN
WRDI
RDSR
WRSR
READ
WRITE
WPEN
Bit 7
Bit 6
X
Instruction Format
0000 X110
0000 X100
0000 X101
0000 X001
0000 X011
0000 X010
Bit 5
X
Bit 4
X
Set Write Enable Latch
Reset Write Enable Latch
Read Status Register
Write Status Register
Read Data from Memory Array
Write Data to Memory Array
Operation
Bit 3
BP1
Bit 2
BP0
AT25P1024
Bit 1
WEN
Bit 0
RDY
CC
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