HP 86060C Series, Руководство пользователя

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4-7
Programming
Programming over HP-IB
Programming over HP-IB
This section describes the HP-IB interface functions and some general con-
cepts. In general, these functions are defined by IEEE 488.2. They deal with
general interface management issues, as well as messages which can be sent
as interface commands.
Default address The HP-IB address is factory preset to 711. To change the HP-IB address,
press
LOCAL . The last two digits of the current HP-IB address are displayed. To
enter a different address, press the two numeric keys for that address. For
example:
14 for address 714, then press ENTER .
Command and
data concepts The interface has two modes of operation:
• command mode
• data mode
The bus is in the data mode when the ATN line is false. The data mode is used
to convey device-dependent messages across the bus.
Addressing The address is used to determine which instrument on the interface bus with
which the controller is communicating.
• Each device on the HP-IB resides at a particular address, 0–30.
• The active controller specifies which devices talk and which listen.
• An instrument may be talk addressed, listen addressed, or unaddressed by the
controller.
If the controller addresses the instrument to talk, the instrument remains con-
figured to talk until it receives an interface clear message (IFC), another instru-
ment’s talk address (OTA), its own listen address (MLA), or a universal untalk
command (UNT).
If the controller addresses the instrument to listen, the instrument remains
configured to listen until it receives an interface clear message (IFC), its own
talk address (MTA), or a universal unlisten command (UNL).