Serial digital communications has become quite popular. There are many varieties: among the standard interfaces at the board level, we have UART, SPI and I2C. Digital communication can also be achieved using analog signals. One example is a radio frequency data line that uses changes in analog amplitude, frequency, or phase to wirelessly transmit binary data. There are also high-speed differential interfaces, such as LVDS or USB-based serial communications.
Manchester code: what is it and why use it
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Another version, called differential Manchester coding, is a binary zero code by switching the voltage at the beginning of the bit interval and a binary code of one without a transition at the beginning of the bit interval. In both cases, the transition occurs in the middle of the interval for synchronization purposes. Differential Manchester encoding is used for Token Ring IEEE 802.5 networks.