China Electronics Technology Instruments AV3672 Series, User Manual

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9 Remote control
9.3 Basic Programming Method of VISA Interface
283
ConstanalyzerTimeout = 10000;
The constant analyzerString refers to the instrument descriptor, “GPIB0” refers to the controller, and “16” refers to
the instrument connected to the controller. Assuming that the instrument is connected LAN, the IP address is
“192.168.1.1” and the port number is “1024”, the variable is:
Const char analyzerString [VI_FIND_BUFLEN] = “TCPIPO::192.168.1.1::1024::SOCKET”;
9.3.2.2 Controller Initialization
The following example shows how to establish the communication connection between the VISA library and
instrument (with the specified descriptor).
//Controller initialization: open the default resource manager and return the instrument handle to the analyzer.
voidInitController()
{
ViState state;
state = viOpenDefaultRM(&defaultRM);
state = viOpen(defaultRM, analyzerString, VI_NULL, VI_NULL, &analyzer);
}
9.3.2.3 Instrument Initialization
/*************************************************************************/
The following example shows the initialization of the default instrument state and clearing of the state register. “\n”
refers to the terminator. The character string of each command should be ended with ‘\n’. This will not be described
later.
/*************************************************************************/
voidInitDevice()
{
ViState state;
longretCnt;
state = viWrite(analyzer, "*CLS\n", 5, &retCnt); //reset state register
state = viWrite(analyzer, "*RST\n", 5, &retCnt); //reset instrument
}
9.3.2.4 Query of Instrument Measurement Information
/*************************************************************************/
The following example shows all measurements, windows and traces defined at present.
/*************************************************************************/
voidQueryMesaurement()
{
ViState state;
longretCnt;
charrd_Buf_CW[VI_READ_BUFLEN]; // #define VI_READ_BUFLEN 20
charrd_Buf_LVL[VI_READ_BUFLEN];
// query all measurements of Channel 1