outputslave

Output slave is a term used in the field of computing and industrial automation to describe a subordinate device or module that executes output tasks under the control of a master controller. It is typically part of a master–slave or distributed control architecture, where the master issues commands and the slave carries out the corresponding actions on physical output channels.

An output slave typically provides digital or analog outputs, PWM signals, or control of relays and actuators. It receives instructions from the master to set specific output states, and may support read-back of current output values, fault reports, and status indications. The arrangement aims to localize output actuation while centralizing decision-making at the master.

Where used, the output slave is often implemented as an I/O module on a fieldbus or industrial Ethernet network, and can be a low-cost microcontroller-based device or a remote I/O unit connected to the master via protocols such as Modbus, CANopen, EtherCAT, Profibus, or proprietary schemes. It may include features such as isolation, buffering, timing control, safety interlocks, and diagnostic reporting.

Terminology notes: while widely used in legacy and some industry standards, the term slave is increasingly being replaced with more neutral language in many organizations. In this context, output slave is a role rather than a standalone product, and its precise capabilities depend on the system architecture and the protocol in use. See also master device, input slave, I/O module.