This lesson describes the design and function of I/O (input/output) interfaces and the equipment used to produce and communicate I/O data. • List some types of discrete I/O (input/ output) interfaces • Describe AC/DC and DC/AC conversion in I/O modules • Discuss DC sinking and sourcing • Describe the use of transistor-transistor logic (TTL) • Discuss register/BCD modules and multiplexing • List some types of analog input devices • Describe the use of A/D and D/A converters • Identify the functions of transducers in input field devices • Discuss single-ended and differential configurations
