Data Sheet

24AA128/24LC128/24FC128
DS20001191U-page 12 2010-2021 Microchip Technology Inc. and its subsidiaries
FIGURE 6-1: PAGE WRITE
7.0 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 host, the device initi-
ates the internally timed write cycle. ACK polling can be
initiated immediately. This involves the host sending 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, the Start bit and control byte must be resent.
If the cycle is complete, then the device will return the
ACK and the host can then proceed with the next read
or write command. See Figure 7-1 for flow diagram.
FIGURE 7-1: ACKNOWLEDGE
POLLING FLOW
xx
Bus Activity
Host
SDA Line
Bus Activity
S
T
A
R
T
Control
Byte
Address
High Byte
Address
Low Byte
Data Byte 0
S
T
O
P
A
C
K
A
C
K
A
C
K
A
C
K
Data Byte 63
A
C
K
x = dont care bit
S 1010 0
A
2
A
1
A
0
P
Send
Write Command
Send Stop
Condition to
Initiate Write Cycle
Send Start
Send Control Byte
with R/W = 0
Did Device
Acknowledge
(ACK = 0)?
Next
Operation
No
Yes