S-24CM01C Datasheet, PDF (13/32 Pages) Seiko Instruments Inc – Write protect function during the low power supply voltage

Rev.2.0_02_S
2-WIRE SERIAL E²PROM
S-24CM01C
6. 2 Page write
The page write mode allows up to 256 bytes to be written in a single write operation in the S-24CM01C.
The basic process used to transmit data is the same as byte write, but page write involves sequentially receiving
as much 8-bit write data as the size of the page.
When the S-24CM01C receives a 7-bit device address and a 1-bit read / write instruction code set to “0” following
a start condition, it generates an acknowledge. The S-24CM01C then receives the upper 8-bit word address, and
responds with an acknowledge. The S-24CM01C then receives the lower 8-bit word address, and responds with
an acknowledge. After the S-24CM01C receives 8-bit write data and responds with an acknowledge, it receives 8-
bit write data corresponding to the next word address, and generates an acknowledge. The S-24CM01C repeats
reception of 8-bit write data and generation of acknowledges in succession. The S-24CM01C can receive as
much write data as the maximum page size.
Receiving a stop condition initiates a write cycle of the area starting from the designated memory address and
with a page size equal to the received write data.
S
W
T
R
A
I
R
DEVICE
T
UPPER
LOWER
T
ADDRESS E WORD ADDRESS (n)
WORD ADDRESS (n)
SDA LINE
1 0 1 0 A2 A1 P0 0 _{W15 W14 W13 W12 W11 W10 W9 W8 W7 W6 W5 W4 W3 W2 W1 W0 D7}
M
LR A
A
A
S
S/ C
C
C
B
BW K
K
K
DATA (n)
S
T
O
DATA (n+x)
P
D0 D7
D0
Figure 12 Page Write
In the S-24CM01C, the lower 8 bits of the word address are automatically incremented every time the
S-24CM01C receives 8-bit write data. If the size of the write data exceeds 256 bytes, the upper 8 bits of the word
address and the page address (P0) remain unchanged, and the lower 8 bits are rolled over so that the last
256-byte data that the S-24CM01C received is overwritten.
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