C Programming Examples Using Vtl; Typical Example Program Contents - Agilent Technologies ESA-E Series Programmer's Manual

Programming Examples

C Programming Examples using VTL

C Programming Examples using VTL
The programming examples that are provided in this guide are written
using the C programming language and the 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 "HP VISA Transition Library", HP part number
E2090-90026.) If you are using the National Instruments VISA library,
most of this information will still apply, but the include and library files
will be in different subdirectories. Also, this information assumes a
computer running a Windows 95 operating system with an HP/Agilent
82341C HP-IB interface card is being used. The following topics are
included:
"Typical Example Program Contents" on page 3-4
"Linking to VTL Libraries" on page 3-5
"Compiling and Linking a VTL Program" on page 3-5
"Example Program" on page 3-7
"Including the VISA Declarations File" on page 3-7
"Opening a Session" on page 3-8
"Device Sessions" on page 3-8
"Addressing a Session" on page 3-10
"Closing a Session" on page 3-11

Typical Example Program Contents

The following is a summary of the VTL function calls used in the
example programs.
This file is included at the beginning of the file to
visa.h
provide the function prototypes and constants defined
by VTL.
The ViSession is a VTL data type. Each object that
ViSession
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.
This function establishes a communication channel
viOpen
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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