Interface chip device

Abstract

An interface chip device, provided for use in a time-division multiplex serial data bus system is operable in a processor interface mode and at least one remote mode wherein the device is capable of directly interfacing with I/O devices. The system does not require software or processing capability for protocol communications or I/O control and, consequently, the communications protocol is transparent to the user, system developer or programmer. The communication protocol of the bus system includes a plurality of commands such that when in the remote mode, the chip device determines the validity of each of the commands and provides an echo response message on the data bus in response to each of the commands except for a broadcast command. The remote modes of the chip device include a remote switch mode, a data input mode, a data output mode or a combination of the remote modes. The chip device is divided into six main functional areas: encoder/decoder, message analyzer, protocol sequencer, data storage, control timers, and input/output controller. The chip device may be used in small remote modules that are located in convenient locations adjacent to the loads they are controlling or switching. The remote modules are controlled by messages from a multiplex data bus controller which are formatted through the communications protocol of the data bus system. The chip device is designed to handle the communications protocol of the data bus system and provide interface between the data bus and other electronic hardware elements.

Dependencies are inferred from the claim text.