Example systems, apparatus, articles of manufacture, and methods are disclosed to implement a single-wire interface protocol to synchronize device states between multiple devices. Example logic circuitry disclosed herein for a first device includes transmit circuitry configured to pull a terminal of the first device to a first logic value for a first duration corresponding to a first command to be communicated via the terminal, wherein the first duration is one of a plurality of at least three possible durations corresponding respectively to a plurality of possible commands including the first command, and the plurality of possible commands is associated with device operation states synchronized between the first device and a second device coupled to the terminal. The example logic circuitry also includes receive circuitry configured to monitor the terminal.