F.W. Bell 7030, Instruction Manual

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F.W. BELL Model 7030 Gauss/Tesla Meter Instruction Manual
Section 7 – Remote Operation 7-3
IEEE-488 BUS
FUNCTIONAL
DESCRIPTION
(Continued)
Pin-8: Not Data Accepted
(NDAC) This line is asserted by a listener until it has
accepted a data byte.
Pin-9: Interface Clear
(IFC) Asserted by the system controller to force all
other devices to go idle.
Pin-10: Service Request
(SRQ) This line can be asserted by any device requiring
service.
Pin-11: Attention (ATN)
Asserted by the controller to indicate that the
byte on the data bus is an interface command.
Pin-12: Not Connected
Pin-17: Remote Enable
(REN) Asserted by the system controller to tell the
systems receiving data that they can actually use
the data, and that their front panel controls are
locked out.
Pin-18,19, 20. 21, 22, 23.
24 Ground (GND) These are the common return lines for all other
signals except earth ground (Pin-12).
Each device on the system bus must be assigned a unique address ranging
from 00 to 31 decimal.
RS-232
FUNCTIONAL
DESCRIPTION The instrument has been designed to interface directly to a 9-pin “D” serial
connector on most personal computers using a straight-through cable. This
means Pin-1 on the instrument is connected to Pin-1 on the computer, Pin-2
to Pin-2, etc. The serial transmission characteristics such as baud rate,
parity setting, etc. are defined in the COMMUNICATIONS menu. These
settings must match those of the computer.
A set of controls lines are used to indicate the overall status of the instrument
and computer. The instrument asserts the Data-Terminal-Ready (DTR) to
inform the computer that it is powered up, initialized and ready for
communications. Likewise the computer asserts Data-Set-Ready (DSR) to
indicate that it is ready for communications.