8163A/B, 8164A/B & 8166A/B Mainframes Programming Guide
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The Keysight 816x VXIplug&play Instrument Driver
7
Opening an Instrument Session
To control an instrument from a program, you must open a communication
path between the computer/controller and the instrument. This path is
known as an instrument session, and is opened with the function
ViStatus hp816x_init( ViRsrc InstrDesc, ViBoolean id_query, ViBoolean
reset, ViPSession instrumentHandle );
Instruments are assigned a handle when the instrument session is opened.
The handle, which is a pointer to the instrument, is the first parameter
passed in all subsequent calls to driver functions.
The parameters of the function
hp816x_init
include:
•
ViRsrc InstrDesc
: the address of the instrument
•
ViBoolean id_query:
a Boolean flag which indicates if in-system
verification should be performed.
Passing
VI_TRUE
(1) will perform an in-system verification; passing
VI_FALSE (0) will not.
If you set id_query to false, you can use the generic functions of the
instrument driver with other instruments.
•
ViBoolean reset:
a Boolean flag which indicates if the instrument
should be reset when it is opened.
Passing VI_TRUE (1) will perform a reset when the session is opened;
passing VI_FALSE (0) will not perform a reset,
•
ViPSession instrumentHandle:
a pointer to an instrument session.
InstrumentHandle is the handle which addresses the instrument, and is
the first parameter passed in all driver functions.
• Successful completion of this function returns VI_SUCCESS
