I2C Framing


Communication is byte-based, with an ack bit
When the master transmits, the slave must ack or nack
When the slave transmits, the master must ack or nack

Everything starts with "start"

Everything stops with "stop"

Frames are master-driven, and each addresses a single slave
There is no such thing as auto-detection
Still you can probe for slave presence
Send its address, look for ack, abort