AK6004A_02 Datasheet, PDF (7/16 Pages) Asahi Kasei Microsystems – I2C bus 4K / 16Kbit Serial CMOS EEPROM

ASAHI KASEI
[AK6004A/08A]
Functional Description
„ WRITE Operations
BYTE WRITE
A write operation requires a word address following the slave address word (R/W=0) and
acknowledge. The word address is comprised of eight bits and provides access to any one of the
512/2048 words. Upon receipt of the word address the AK6004A/08A responds with an
acknowledge, and awaits the next eight bits of data, again, responding with an acknowledge.
The master then terminates the transfer by generating a stop condition, at which time the
AK6004A/08A begins the internal write cycle to the nonvolatile memory. While the internal write
cycle is in progress the AK6004A/08A inputs are disable, and the device will not respond to any
requests from the master.
S
T
Bus Activity:
Master
A
R
T
SDA LINE S
Bus Activity:
AK6004A/08A
SLAVE
ADDRESS
WORD
ADDRESS
S
T
DATA
O
P
P
※
A
C
A7 - A0
A
C
A
C
K
K
K
※: S2, S1, A8 (AK6004A) or A10, A9, A8 (AK6008A)
BYTE WRITE
PAGE WRITE
The AK6004A/08A is capable of a sixteen byte page write operation.
It is initiated in the same manner as the byte write operation. But instead of terminating the write
cycle after the first data word is transferred, the master can transmit up to fifteen more words. After
the receipt of each word, the AK6004A/08A will respond with an acknowledge. The master then
terminates the transfer by generating a stop condition, at which time the AK6004A/08A begins the
internal write cycle to the nonvolatile memory.
After the receipt of each word, the four lower order address pointer bits are internally incremented
by one. The higher order five/seven bits of the word address remains constant.
AK6004A: When the highest address is reached (X XXXX 1111), the address counter rolls over to
address "X XXXX 0000" allowing the read cycle to be continued indefinitely.
AK6008A: When the highest address is reached (XXX XXXX 1111), the address counter rolls over
to address "XXX XXXX 0000" allowing the read cycle to be continued indefinitely.
If the master should transmit more than sixteen words prior to generating the stop condition, the
address counter will "roll over" and the previously written data will be overwritten. When the
master transmit eighteen words prior to the stop condition, seventeenth word will be overwritten to
first word, and eighteenth word will be overwritten to second word.
Bus Activity:
Master
S
T
A SLAVE
R ADDRESS
T
WORD
ADDRESS(n)
DATA(n)
DATA(n+1)
SDA LINE S
Bus Activity:
AK6004A/08A
※
A
C
A7 - A0
A
C
K
K
A
C
K
A
C
K
※: S2, S1, A8 (AK6004A) or A10, A9, A8 (AK6008A)
PAGE WRITE
S
T
DATA(n+15) O
P
P
A
C
K
DAI01E-02
-7-
2002/11