I2c Overview Info

The master pulls the SDA line low while SCL remains high.

Each slave device has a unique 7-bit (or 10-bit) address, eliminating the need for complex Chip Select (CS) lines used in SPI.

The slave device with the matching address responds with an Acknowledge (ACK) bit (low), signaling it is ready, or a Not Acknowledge (NACK) bit (high).

I2C (Inter-Integrated Circuit), often pronounced "eye-squared-see" or "eye-two-see," is a popular, synchronous, multi-master/multi-slave communication protocol invented in 1982 by Philips Semiconductors (now NXP). It is used for short-distance, intra-board communication between a processor and low-speed peripherals such as sensors, LCDs, and memory chips. Its hallmark is using only two wires for communication, making it highly efficient for managing multiple devices on a single bus.

The master sends the 7-bit unique address of the target slave, followed by a R/W bit (0 for write, 1 for read).

I2C communication is master-controlled. The master initiates, manages, and terminates communication, generating the clock signal.