A discrete input, abbreviated as DI, in contrast to an analog input, refers to a type of signal or data that can only take on a limited set of distinct values. Discrete inputs are often binary, meaning they can have only two possible states: either a TRUE or FALSE, 1 or 0, or ON of OFF as an input signal.
In digital systems, discrete inputs are commonly used to represent information in a way that is easily processed by digital circuits. For example, a switch can be considered a discrete input device because it can be either in an "on" state (represented as 1) or an "off" state (represented as 0). Similarly, digital sensors, such as those used in many electronic devices, often produce discrete signals.
Discrete inputs are fundamental to digital computing and are used to encode information in a way that is easily interpreted by binary logic circuits. Microcontrollers and computers typically process information in the form of discrete inputs, enabling the execution of digital algorithms and logical operations. The conversion of continuous signals (analog) to discrete signals (digital) is often facilitated by analog-to-digital converters (ADCs).