I-O Display Systems Basic I/O Product manual Introduction, Protocol Compatibility

Introduction 1

Protocol Compatibility:

The BASIC I/O AD instruction set core complies 100% with that of the OPTO- 22 Optomux

™. With this ASCII character, speak-only-when-spoken-to protocol, a Host transmits inquiry requests to the BASIC I/O AD to determine the status of its various process inputs. Similarly, the software in the Host computer makes control decisions and transmits instructions to the BASIC I/O AD, which in turn, makes the proper changes to its various outputs. Both the Host and its communications link are essential elements in this data acquisition and process control scheme.

Originally the protocol only allowed for all analog or all digital I/O chassis. Depending on application requirements, each BASIC I/O AD can respond to pup to three different function addresses. With their abbreviations they are:

MC Master Unit Control function address

MD Master Unit Digital I/O function address

MA Master Unit Analog I/O function address

It is this multiple function addressing capability of BASIC I/O ADs that allows them to utilize, without modification, software developed for competitive products. Similarly BASIC I/O ADs can operate simultaneously on the same network with these products.

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