Valhalla Scientific 4300C, Руководство по эксплуатации

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Remote Operations
IEEE Interface
The purpose of the IEEE Standard 488 is to allow for interconnection of programmable instruments with
minimum engineering. The intent is to remove the need for adapters and the numerous types of patching
cables often encountered with other forms of interfaces. The IEEE-488 standard defines a system
configuration for programmable instruments such as calculators, voltmeters and other types of peripheral
devices produced by various manufacturers. It provides a set of rules for establishing defined
communication links with a high degree of compatibility yet maintaining flexibility between independently
manufactured products.
Definitions
Listed below are definitions of the terms used to describe the IEEE-488 interface:
Bus: A data link which is usually a set of several parallel wires within a multi-wire cable.
Bi-Directional Bus: A "highway" used for two-way communication, with input and output data being
carried on the same lines.
Bit-Parallel: A data transmission method in which all the bits composing an item of data are present
simultaneously on a group of wires in a bus.
Byte: A group of eight data bits which is treated as a single item of data.
Byte-Serial: A data transmission method in which information, in bit-parallel bytes, is transferred
sequentially between devices.
Device Dependent Message: A message containing commands or data intended for a specific device.
Handshake: An exchange of signals between two devices which is used to control the transfer of data
between them.
Interface: The part of an instrument or system which enables it to be connected to another via a bus.
Interface Message: A message intended for interface management.
Local Operation: Operation of a device by its front panel controls (also referred to as Manual Control).
Remote Operation: Operation of device under the control of another via the bus.