F.W. Bell 8000 series, Инструкция по эксплуатации

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F.W. BELL 8000 Series Gauss/Tesla Meter Instruction Manual
Section 8 – Remote Operation 8-10
IEEE-488
(GPIB) BUS
Functional
Description
The IEEE-488 (GPIB) instrumentation bus allows up to 15 instruments to be
connected together in a "daisy chain" fashion.
Any device connected to the bus is capable of acting in any of three basic
roles: controller, talker and listener. As a controller, the device dictates which
devices act as talkers and listeners. There is only one controller at any given
time, called the "system controller." This is normally the computer in an
automated data acquisition system. As a talker, the device sends device-
dependent data across the bus, but only when commanded to do so by the
controller. As a listener, the device receives device-dependent data from a
talker, and there can be many listeners at any given time.
The bus is implemented on a standard 24-pin connector, as shown below.
Pin-1,2,3,4,13,14,15,16:
Data (DIO) These are the eight data lines DIO1 through
DIO8 respectively.
Pin-5: End or Identify (EIO) The line is normally asserted by a talker to
indicate the end of a multiple byte data
transfer. When EOI is asserted along with
ATN (Attention), it indicates that the
controller is conducting a parallel poll.
Pin-6: Data Available (DAV) This line is asserted when a talker puts a
data byte on the bus.
Figure 8-7 IEEE-488 (GPIB) Connector