The basic byte-based messaging schemes of I²C and SPI map easily onto I3C. Additionally, a set of common command codes (CCCs) has been defined for standard operations like enabling and disabling events, managing I3C‑specific features (e.g., Dynamic Addressing, Timing Control, etc.), and other functions. CCCs can be either Broadcasted (i.e., sent to all Devices on the I3C Bus), or else Directed at a particular Device on the I3C Bus.
CCCs do not interfere with, and do not consume any of the message space of, normal Master‑to‑Slave communications. That is, I3C provides a separate namespace for CCCs.