24AA64_02 Datasheet, PDF (9/24 Pages) Microchip Technology – 64K I2C™ Serial EEPROM

5.0 ACKNOWLEDGE POLLING
Since the device will not acknowledge during a write
cycle, this can be used to determine when the cycle is
complete (this feature can be used to maximize bus
throughput). Once the STOP condition for a write com-
mand has been issued from the master, the device ini-
tiates the internally timed write cycle. ACK polling can
be initiated immediately. This involves the master send-
ing a START condition followed by the control byte for
a write command (R/W = 0). If the device is still busy
with the write cycle, then no ACK will be returned. If no
ACK is returned, then the START bit and control byte
must be re-sent. If the cycle is complete, then the
device will return the ACK and the master can then pro-
ceed with the next read or write command. See
Figure 5-1 for flow diagram.
24AA64/24LC64
FIGURE 5-1: ACKNOWLEDGE POLLING
FLOW
Send
Write Command
Send STOP
Condition to
Initiate Write Cycle
Send Start
Send Control Byte
with R/W = 0
Did Device
Acknowledge
NO
(ACK = 0)?
YES
Next
Operation
 2002 Microchip Technology Inc.
DS21189F-page 9