Input and output devices may either be digital or analog form: digital products are finite values symbolized in values of just one or , analog products are infinite values, and measure ranges of currents or siemens s7-1200. Inputs or providers are switches, sensors, and smart devices in analog or digital forms. Outputs could be motor starters, lights, valves, and smart devices. Various kinds of I/O modules are for sale to obtain the right configuration to operate your machine.