Rainbow Electronics AT25256A - Manual (Page 6)

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AT25128A/256A [Preliminary]
3404A–SEEPR–10/03
SPI Serial Interface
Functional
Description
The AT25128A/256A is designed to interface directly with the synchronous serial
peripheral interface (SPI) of the 6800 type series of microcontrollers.
The AT25128A/256A utilizes an 8-bit instruction register. The list of instructions and
their operation codes are contained in Table 1. All instructions, addresses, and data are
transferred with the MSB first and start with a high-to-low CS transition..
AT25128A/256A
Table 1. Instruction Set for the AT25128A/256A
Instruction Name Instruction Format Operation
WREN 0000 X110 Set Write Enable Latch
WRDI 0000 X100 Reset Write Enable Latch
RDSR 0000 X101 Read Status Register
WRSR 0000 X001 Write Status Register
READ 0000 X011 Read Data from Memory Array
WRITE 0000 X010 Write Data to Memory Array