Datasheet

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transition from. Bus stop condition is generated in an idle state. The stop
condition abbreviated as P.
Start and stop conditions diagram shown in Figure 7.
Figure 7: Schematic start and stop conditions
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Byte transfer format
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C bus to send and receive data in bytes. Each byte is transmitted to the SDA line must be 8.
The number of bytes per transfer is unrestricted. First, is the highest transmission bit data (MSB bit
7), the last transmission is lowest (LSB, bit 0). Also must be followed by an acknowledge bit after
each byte (ACK). C transmission data shown in Figure 8.
Figure 8: Data Transfer I2 C bus
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C-bus response
In the I
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C bus data transfer process, one byte per transmission, must acknowledge with a status
bit. Receiving reception data to inform the transmitter can acknowledge bit. Acknowledge bit hosts
still generated clock pulse, and acknowledge the state of the bit data follow the principle of "Who
receives who produce", that always generates acknowledge bit by the receiver, the receiver clock
pulse response during the SDA line must be low, making it a high level during this clock pulse is
stable low (see Figure 9), of course, setup and hold times must be considered (for details please refer
to table 6). When sending data from the host to the machine, generating an acknowledge bit from the
slave; master data received from the slave, the master generates an acknowledge bit.
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C bus standards: Acknowledge bit 0 indicates the receiver acknowledge (ACK), often
abbreviated as A; it is a representation of non-response (NACK), often abbreviated as NA. The
transmitter then sends LSB, should release the SDA line (pull SDA), in order to wait for the receiver
generates an acknowledge bit.
If the receiver is receiving at the time of completion of the last byte of data, or can’t receive
more data should be generated to notify the non-response signal transmitter. If you find a receiver
transmitter generates a non-responder status, you should send a termination.