X24257 Datasheet, PDF (6/19 Pages) Xicor Inc. – 400kHz 2-Wire Serial EEPROM with Block Lock

X24257 – Preliminary Information
Stop and Write Modes
Figure 7. Acknowledge Polling Sequence
Stop conditions that terminate write operations must
be sent by the master after sending at least 1 full data
byte and it’s associated ACK signal. If a stop is issued
in the middle of a data byte, or before 1 full data byte +
ACK is sent, then the device will reset itself without
performing the write. The contents of the array will not
be affected.
Acknowledge Polling
The maximum write cycle time can be significantly
reduced using Acknowledge Polling. To initiate
Acknowledge Polling, the master issues a start condi-
tion followed by the Slave Address Byte for a write or
read operation. If the device is still busy with the inter-
nal write cycle, then no ACK will be returned. If the
device has completed the internal write operation, an
ACK will be returned and the host can then proceed
with the read or write operation. Refer to Figure 7.
Obsolete
Byte Load Completed
by Issuing Stop.
Enter ACK Polling
t _Issue
Start
c _{Issue Slave}
u ^{Address Byte}
(Read or Write)
d _ACK
NO
Returned?
o_YES
r_High
P^Voltage
Issue Stop
Cycle Complete.
NO
Continue
Sequence?
YES
Continue Normal
Read or Write
Command Sequence?
Issue Stop
PROCEED
REV 1.1.1 10/15/00
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Characteristics subject to change without notice. 6 of 19