8
AT45DB161E
8782K–DFLASH–7/2017
clock frequencies does not require the clocking in of dummy bytes after the address byte sequence. To perform a
Continuous Array Read using the standard DataFlash page size (528 bytes), the CS pin must first be asserted, and then
an opcode of 03h must be clocked into the device followed by three address bytes. The first 12 bits (PA11 - PA0) of the
22-bit address sequence specify which page of the main memory array to read and the last 10 bits (BA9 - BA0) of the 22-
bit address sequence specify the starting byte address within the page. To perform a Continuous Array Read using the
binary page size (512 bytes), the opcode 03h must be clocked into the device followed by three address bytes (A20 -
A0). Following the address bytes, additional clock pulses on the SCK pin will result in data being output on the SO pin.
The CS pin must remain low during the loading of the opcode, the address bytes, and the reading of data. When the end
of a page in the main memory is reached during a Continuous Array Read, the device will continue reading at the
beginning of the next page with no delays incurred during the page boundary crossover (the crossover from the end of
one page to the beginning of the next page). When the last bit in the main memory array has been read, the device will
continue reading back at the beginning of the first page of memory. As with crossing over page boundaries, no delays will
be incurred when wrapping around from the end of the array to the beginning of the array.
A low-to-high transition on the CS pin will terminate the read operation and tri-state the output pin (SO). The maximum
SCK frequency allowable for the Continuous Array Read is defined by the fCAR2 specification. The Continuous Array
Read bypasses both data buffers and leaves the contents of the buffers unchanged.
5.5 Continuous Array Read (Low Power Mode: 01h Opcode)
This command is ideal for applications that want to minimize power consumption and do not need to read the memory
array at high frequencies. Like the 03h opcode, this Continuous Array Read command allows reading the main memory
array sequentially without the need for dummy bytes to be clocked in after the address byte sequence. The memory can
be read at clock frequencies up to maximum specified by fCAR3. To perform a Continuous Array Read using the standard
DataFlash page size (528 bytes), the CS pin must first be asserted, and then an opcode of 01h must be clocked into the
device followed by three address bytes. The first 12 bits (PA11 - PA0) of the 22-bit address sequence specify which page
of the main memory array to read and the last 10 bits (BA9 - BA0) of the 22-bit address sequence specify the starting
byte address within the page. To perform a Continuous Array Read using the binary page size (512 bytes), the opcode
01h must be clocked into the device followed by three address bytes (A20 - A0). Following the address bytes, additional
clock pulses on the SCK pin will result in data being output on the SO pin.
The CS pin must remain low during the loading of the opcode, the address bytes, and the reading of data. When the end
of a page in the main memory is reached during a Continuous Array Read, the device will continue reading at the
beginning of the next page with no delays incurred during the page boundary crossover (the crossover from the end of
one page to the beginning of the next page). When the last bit in the main memory array has been read, the device will
continue reading back at the beginning of the first page of memory. As with crossing over page boundaries, no delays will
be incurred when wrapping around from the end of the array to the beginning of the array.
A low-to-high transition on the CS pin will terminate the read operation and tri-state the output pin (SO). The maximum
SCK frequency allowable for the Continuous Array Read is defined by the fCAR3 specification. The Continuous Array
Read bypasses both data buffers and leaves the contents of the buffers unchanged.
5.6 Main Memory Page Read
A Main Memory Page Read allows the reading of data directly from a single page in the main memory, bypassing both of
the data buffers and leaving the contents of the buffers unchanged. To start a page read using the standard DataFlash
page size (528 bytes), an opcode of D2h must be clocked into the device followed by three address bytes (which
comprise the 22-bit page and byte address sequence) and four dummy bytes. The first 12 bits
(PA11 - PA0) of the 22-bit address sequence specify the page in main memory to be read and the last 10 bits
(BA9 - BA0) of the 22-bit address sequence specify the starting byte address within that page. To start a page read using
the binary page size (512 bytes), the opcode D2h must be clocked into the device followed by three address bytes and
four dummy bytes. The first 12 bits (A20 - A9) of the 21-bit address sequence specify which page of the main memory
array to read, and the last nine bits (A8 - A0) of the 21-bit address sequence specify the starting byte address within that
page. The dummy bytes that follow the address bytes are sent to initialize the read operation. Following the dummy
bytes, the additional pulses on SCK result in data being output on the SO (serial output) pin.