Pass Control Involved With An External Controller; Pass Control - Agilent Technologies 4294A Programming Manual

Using HP Instrument BASIC

Pass Control Involved with an External Controller

Pass Control Involved with an External Controller
Here follows the description of how to exchange the control priority (pass control) between
Instrument BASIC and an external controller.

Pass control

To deliver active control from an external controller to HP Instrument BASIC, execute
pass control on the external controller side. For example, with the GPIB address set to 17 in
the 4294A, the following in HP BASIC serves the purpose.
PASS CONTROL 717
When the 4294A has the control priority, the 4294A can specify another device on the
GPIB bus to freely exchange (talk/listen) data. Similarly to the system controller, the
4294A can transmit data either to a printer or to a plotter (talk) and receive (listen)
responses either from the printer or from the plotter.
NOTE The features to assert the interface clear line (IFC) and the remote enable line (REN)
appertain to the system controller. Even though HP Instrument BASIC is turned to an
active controller, it cannot use these features.
ABORT 7 Asserting Interface Clear Line (IFC)
REMOTE 7 Asserting Remote Enable Line (REN)
To return the control priority to the 4294A, execute the following on the Instrument BASIC
side.
PASS CONTROL 721
Also, resetting the GPIB bus as given below causes the control priority to return to the
system controller.
ABORT 7
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