at45db041a-cc ATMEL Corporation, at45db041a-cc Datasheet - Page 6

• Manufacturer Part Number: at45db041a-cc
• Description: At45db041a 4-megabit 2.5-volt Only Serial Dataflash
• Manufacturer: ATMEL Corporation

Block Erase Addressing
MAIN MEMORY PAGE PROGRAM THROUGH BUFFER:
This operation is a combination of the Buffer Write and
Buffer to Main Memory Page Program with Built-in Erase
operations. Data is first shifted into buffer 1 or buffer 2 from
the SI pin and then programmed into a specified page in
the main memory. To initiate the operation, an 8-bit
opcode, 82H for buffer 1 or 85H for buffer 2, must be fol-
lowed by the four reserved bits and 20 address bits. The 11
most significant address bits (PA10-PA0) select the page in
the main memory where data is to be written, and the next
nine address bits (BFA8-BFA0) select the first byte in the
buffer to be written. After all address bits are shifted in, the
part will take data from the SI pin and store it in one of the
data buffers. If the end of the buffer is reached, the device
will wrap around back to the beginning of the buffer. When
there is a low-to-high transition on the CS pin, the part will
first erase the selected page in main memory to all 1s and
then program the data stored in the buffer into the specified
page in the main memory. Both the erase and the program-
ming of the page are internally self-timed and should take
place in a maximum of time t
register will indicate that the part is busy.
Additional Commands
MAIN MEMORY PAGE TO BUFFER TRANSFER: A page
of data can be transferred from the main memory to either
buffer 1 or buffer 2. To start the operation, an 8-bit opcode,
53H for buffer 1 and 55H for buffer 2, must be followed by
the four reserved bits, 11 address bits (PA10-PA0) which
specify the page in main memory that is to be transferred,
and nine don’t care bits. The CS pin must be low while tog-
gling the SCK pin to load the opcode, the address bits, and
the don’t care bits from the SI pin. 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. During the
6
PA10
0
0
0
0
1
1
1
1
•
•
•
PA9
0
0
0
0
1
1
1
1
•
•
•
AT45DB041A
PA8
0
0
0
0
1
1
1
1
•
•
•
EP
. During this time, the status
PA7
0
0
0
0
1
1
1
1
•
•
•
PA6
0
0
0
0
1
1
1
1
•
•
•
PA5
0
0
0
0
1
1
1
1
•
•
•
transfer of a page of data (t
read to determine whether the transfer has been completed
or not.
MAIN MEMORY PAGE TO BUFFER COMPARE: A page
of data in main memory can be compared to the data in
buffer 1 or buffer 2. To initiate the operation, an 8-bit
opcode, 60H for buffer 1 and 61H for buffer 2, must be fol-
lowed by 24 address bits consisting of the four reserved
bits, 11 address bits (PA10-PA0) which specify the page in
the main memory that is to be compared to the buffer, and
nine don’t care bits. The CS pin must be low while toggling
the SCK pin to load the opcode, the address bits, and the
don’t care bits from the SI pin. On the low-to-high transition
of the CS pin, the 264 bytes in the selected main memory
page will be compared with the 264 bytes in buffer 1 or
buffer 2. During this time (t
cate that the part is busy. On completion of the compare
operation, bit 6 of the status register is updated with the
result of the compare.
AUTO PAGE REWRITE: This mode is only needed if multi-
ple bytes within a page or multiple pages of data are
modified in a random fashion. This mode is a combination
of two operations: Main Memory Page to Buffer Transfer
and Buffer to Main Memory Page Program with Built-in
Erase. A page of data is first transferred from the main
memory to buffer 1 or buffer 2, and then the same data
(from buffer 1 or buffer 2) is programmed back into its
original page of main memory. To start the rewrite opera-
tion, an 8-bit opcode, 58H for buffer 1 or 59H for buffer 2,
must be followed by the four reserved bits, 11 address bits
(PA10-PA0) that specify the page in main memory to be
rewritten, and nine additional don’t care bits. When a low-
to-high transition occurs on the CS pin, the part will first
transfer data from the page in main memory to a buffer and
then program the data from the buffer back into same page
PA4
0
0
1
1
0
0
1
1
•
•
•
PA3
0
1
0
1
0
1
0
1
•
•
•
PA2
X
X
X
X
X
X
X
X
•
•
•
XFR
XFR
PA1
), the status register will indi-
X
X
X
X
X
X
X
X
), the status register can be
•
•
•
PA0
X
X
X
X
X
X
X
X
•
•
•
Block
252
253
254
255
0
1
2
3
•
•
•