Agilent Technologies E4406A VSA manual C Programming Using VTL, Typical Example Program Contents

Programming Fundamentals

C Programming Using VTL

C Programming Using VTL

The programming examples that are provided are written using the C programming language and the HP/Agilent VTL (VISA transition library). This section includes some basic information about programming in the C language. Refer to your C programming language documentation for more details. (This information is taken from the manual “VISA Transition Library”, part number

E2090-90026.) The following topics are included:

“Typical Example Program Contents” on page 113. “Linking to VTL Libraries” on page 114.

“Compiling and Linking a VTL Program” on page 114. “Example Program” on page 116.

“Including the VISA Declarations File” on page 117. “Opening a Session” on page 117.

“Device Sessions” on page 118.

“Addressing a Session” on page 119. “Closing a Session” on page 121.

Typical Example Program Contents

The following is a summary of the VTL function calls used in the example programs.

visa.h	This file is included at the beginning of the file to
	provide the function prototypes and constants defined
	by VTL.
ViSession	The ViSession is a VTL data type. Each object that
	will establish a communication channel must be
	defined as ViSession.

viOpenDefaultRM You must first open a session with the default resource manager with the viOpenDefaultRM function. This function will initialize the default resource manager and return a pointer to that resource manager session.

viOpen	This function establishes a communication channel
	with the device specified. A session identifier that can
	be used with other VTL functions is returned. This call
	must be made for each device you will be using.

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