CAT1025 CATALYST [Catalyst Semiconductor], CAT1025 Datasheet - Page 10

• Manufacturer Part Number: CAT1025
• Description: Supervisory Circuits with I2C Serial 2k-bit CMOS EEPROM and Manual Reset
• Manufacturer: CATALYST [Catalyst Semiconductor]

Figure 7. Slave Address Bits
ACKNOWLEDGE
After a successful data transfer, each receiving device
is required to generate an acknowledge. The
acknowledging device pulls down the SDA line during
the ninth clock cycle, signaling that it received the 8 bits
of data.
The CAT1024/25 responds with an acknowledge after
receiving a START condition and its slave address. If the
device has been selected along with a write operation,
it responds with an acknowledge after receiving each 8-
bit byte.
When the CAT1024/25 begins a READ mode it transmits
8 bits of data, releases the SDA line and monitors the
line for an acknowledge. Once it receives this
acknowledge, the CAT1024/25 will continue to transmit
data. If no acknowledge is sent by the Master, the device
terminates data transmission and waits for a STOP
condition.
CAT1024, CAT1025
Doc. No. 3008, Rev. M
Figure 6. Acknowledge Timing
Figure 5. Start/Stop Timing
Default Configuration
CAT
FROM TRANSMITTER
FROM RECEIVER
SDA
SCL
DATA OUTPUT
DATA OUTPUT
SCL FROM
MASTER
1
START BIT
START
0
1
0
1
0
10
WRITE OPERATIONS
Byte Write
In the Byte Write mode, the Master device sends the
START condition and the slave address information (with
the R/W bit set to zero) to the Slave device. After the Slave
generates an acknowledge, the Master sends a 8-bit
address that is to be written into the address pointers of
the device. After receiving another acknowledge from the
Slave, the Master device transmits the data to be written
into the addressed memory location. The CAT1024/25
acknowledges once more and the Master generates the
STOP condition. At this time, the device begins an
internal programming cycle to non-volatile memory. While
the cycle is in progress, the device will not respond to any
request from the Master device.
0
0
R/W
8
ACKNOWLEDGE
STOP BIT
9