ATSHA204 ATMEL [ATMEL Corporation], ATSHA204 Datasheet - Page 22

• Manufacturer Part Number: ATSHA204
• Description: Atmel CryptoAuthentication
• Manufacturer: ATMEL [ATMEL Corporation]

Figure 6-2. Start and Stop Conditions on I
Figure 6-3. NACK and ACK Conditions on I
by Transmitter
Multiple ATSHA204 devices can easily share the same I
for each device on the bus. Because six of the bits of the device address are programmable, the ATSHA204 can also share
the I
programmed according the input thresholds desired, and is fixed in a particular application.
Data Output
Data Output
by Receiver
SCL from
2
Start:
Stop:
Acknowledge (ACK): On the ninth clock cycle after every address or data byte is transferred, the receiver will pull the
Not Acknowledge (NACK): Alternatively, on the ninth clock cycle after every address or data byte is transferred, the
C interface with any standard I
SDA
SCL
Master
Condition
Condition
A high-to-low transition of SDA with SCL high is a start condition, which must precede all commands.
A low-to-high transition of SDA with SCL high is a stop condition. After this condition is received by the
device, the current I/O transaction ends. On input, if the device has sufficient bytes to execute a command,
the device transitions to the busy state and begins execution. The stop condition should always be sent after
any packet sent to the device.
SDA pin low to acknowledge proper reception of the byte.
receiver can leave the SDA pin high to indicate that there was a problem with the reception of the byte or
that this byte completes the block transfer.
Start
Start
S
S
1
2
C device, including any serial EEPROM. Bit 3 (also known as TTL Enable) must be
2
C Interface
2
2
C Interface
2
C interface if the I2C_Device address byte is programmed differently
Not Acknowledge
8
Acknowledge
Acknowledgement
Clock Pulse for
Condition
9
Atmel ATSHA204 [DATASHEET]
Stop
P
8740D−CRYPTO−3/12
22