The Human Interface Device protocol was first defined for USB attached input devices (e.g. keyboards, mice, remote controls, buttons, etc.). The protocol itself is bus agnostic and has been ported across other transports, including Bluetooth™ and other wired and wireless technologies.
This specification document will build on the USB defined specification and identify the protocol, procedures and features for simple input devices to talk HID over I2C. This specific document will provide details on the DEVICE side of the protocol. Details on HOST side optimizations are captured in a separate specification.