X24012
Stop Condition
The X24012 will respond with an acknowledge after
recognition of a start condition and its slave address. If
both the device and a write operation have been se-
lected, the X24012 will respond with an acknowledge
after the receipt of each subsequent eight bit word.
All communications must be terminated by a stop condi-
tion, which is a LOW to HIGH transition of SDA when SCL
is HIGH. The stop condition is also used by the X24012 to
placethedeviceintothestandbypowermodeafteraread
sequence. A stop condition can only be issued after the
transmitting device has released the bus.
In the read mode the X24012 will transmit eight bits of
data, release the SDA line and monitor the line for an
acknowledge. If an acknowledge is detected and no
stop condition is generated by the master, the X24012
will continue to transmit data. If an acknowledge is not
detected, the X24012 will terminate further data trans-
missions. The master must then issue a stop condition
to return the X24012 to the standby power mode and
place the device into a known state.
Acknowledge
Acknowledge is a software convention used to indicate
successful data transfers. The transmitting device will
release the bus after transmitting eight bits. During the
ninth clock cycle the receiver will pull the SDA line LOW
to acknowledge that it received the eight bits of data.
Refer to Figure 3.
Figure 3. Acknowledge Response From Receiver
SCL FROM
MASTER
1
8
9
DATA
OUTPUT
FROM
TRANSMITTER
DATA
OUTPUT
FROM
RECEIVER
3847 FHD F07
START
ACKNOWLEDGE
4
XICOR [ XICOR INC. ]
