Ceyear 3943B, Руководство по эксплуатации, Страница: 98 / 167

6 Remote control
6.4 I/O library
90
6.3.5 Read the State of Measuring Instrument
/*************************************************************************/
The following examples show how to read the set state of the instrument.
/*************************************************************************/
void ReadSettings()
{
ViStatus status;
long retCnt;
char rd_Buf_CW[VI_READ_BUFLEN]; // #define VI_READ_BUFLEN 40
// Query center frequency
status = viWrite(monitor, "FREQ?", 5, &retCnt);
status = viRead(monitor, rd_Buf_CW, VI_READ_BUFLEN, &retCnt);
// Print debugging information
sprint("Freq is %s", rd_Buf_CW);
}
6.3.6 Read the frequency scale
/*************************************************************************/
The following example illustrates how to read the frequency scale measurements.
/*************************************************************************/
void ReadMarker ()
{
ViStatus status;
long retCnt;
char rd_Buf_Marker[VI_READ_BUFLEN]; // #define VI_READ_BUFLEN 20
// Open IF panoramic frequency scale pairs and query frequency scale peaks
status = viWrite(monitor, "CALC:IFP:MARK:MMAX", 18, &retCnt);
status = viWrite(monitor, "CALC:IFP:MARK:MY?", 17, &retCnt);
status = viRead(monitor, rd_Buf_Marker, VI_READ_BUFLEN, &retCnt);
// Print debugging information
sprint("Marker is %s", rd_Buf_Marker);
}
6.4 I/O library

I/O library overview
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
I/O Library installation and configuration
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6.4.1 Overview of I/O Library
I/O library is a pre-written software library for instruments, known as instrument driver. As a software
between the computer and the instrument hardware, it consists of the function library, utility program,
tool kit, etc. It is a combination of a series of software code modules and corresponds to operation of a