AT45DB161D-SU-SL955 ATMEL [ATMEL Corporation], AT45DB161D-SU-SL955 Datasheet - Page 21
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AT45DB161D-SU-SL955
Manufacturer Part Number
AT45DB161D-SU-SL955
Description
16-megabit 2.5-volt or 2.7-volt DataFlash
Manufacturer
ATMEL [ATMEL Corporation]
Datasheet
1.AT45DB161D-SU-SL955.pdf
(56 pages)
10.2.2
Figure 10-4. Read Security Register
11. Additional Commands
11.1
3500M–DFLASH–04/09
Main Memory Page to Buffer Transfer
CS
SO
Reading the Security Register
SI
Each transition
represents 8 bits
Opcode
The Security Register can be read by first asserting the CS pin and then clocking in an opcode
of 77H followed by three dummy bytes. After the last don't care bit has been clocked in, the con-
tent of the Security Register can be clocked out on the SO pins. After the last byte of the
Security Register has been read, additional pulses on the SCK pin will simply result in undefined
data being output on the SO pins.
Deasserting the CS pin will terminate the Read Security Register operation and put the SO pins
into a high-impedance state.
A page of data can be transferred from the main memory to either buffer 1 or buffer 2. To start
the operation for the standard DataFlash page size (528 bytes), a 1-byte opcode, 53H for buffer
1 and 55H for buffer 2, must be clocked into the device, followed by three address bytes com-
prised of 2 don’t care bits, 12 page address bits (PA11 - PA0), which specify the page in main
memory that is to be transferred, and 10 don’t care bits. To perform a main memory page to buf-
fer transfer for the binary page size (512 bytes), the opcode 53H for buffer 1 or 55H for buffer 2,
must be clocked into the device followed by three address bytes consisting of 3 don’t care bits,
12 page address bits (A20 - A9) which specify the page in the main memory that is to be trans-
ferred, and 9 don’t care bits. The CS pin must be low while toggling the SCK pin to load the
opcode and the address bytes from the input pin (SI). The transfer of the page of data from the
main memory to the buffer will begin when the CS pin transitions from a low to a high state. Dur-
ing the transfer of a page of data (t
monitored to determine whether the transfer has been completed.
X
X
XFR
X
), the status register can be read or the RDY/BUSY can be
Data Byte
n
Data Byte
n + 1
Data Byte
n + x
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