Optomuxhttps://documents.opto22.com/1572_Optomux_Protocol_Guide.pdf is a serial (

RS-422 RS-422, also known as TIA/EIA-422, is a technical standard originated by the Electronic Industries Alliance that specifies electrical characteristics of a digital signaling circuit. It was meant to be the foundation of a suite of standards that ...

RS485 RS-485, also known as TIA-485(-A) or EIA-485, is a standard defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. The s ...

) network protocol originally developed by

Opto 22 {{Unreferenced, date=September 2009 Opto 22 is a manufacturing company specializing in hardware and software products for industrial automation, remote monitoring, and data acquisition. The company is based in Southern California and sells solid s ...

in 1982 which is used for industrial automation applications. Optomux is an

ASCII ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because ...

protocol consisting of command messages and response messages containing data from an Optomux unit & contain a message checksum to ensure secure communications. The serial data link is very reliable, over distances up to 4,000 feet and is suitable for extreme safety applications. An Optomux system is typically made up of three main elements: * There must be a host device to poll the Optomux brain boards. * There are the brain boards themselves, anywhere from one to 255 of them. * Each Optomux brain board attaches to an I/O mounting rack, carrying the individual I/O modules.

Limitation

The primary performance limitation of the Optomux system is the slow serial data link. The maximum data rate supported by the Optomux brain boards is 38.4

kbit/s In telecommunications, data-transfer rate is the average number of bits (bitrate), characters or symbols (baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are multi ...

(also dependent on the length of the communication lines). In theory, at maximum speed, the Optomux system should be capable of polling roughly 3,400 digital positions per second, or roughly 600 analog positions per second. This is assuming that all the positions are on the same brain board, which is not possible with Optomux. A more realistic speed figure would be about half of the previous numbers. For faster serial data communication, Opto 22’s Mistic protocol and hardware may be used at speeds to 115.2 kbit/s. Or, a B3000 brain using the Optomux protocol can communicate at similar high speeds.

External links

Optomux protocol user Guide

References

{{List of automation protocols Industrial computing Serial buses Industrial automation