using System;

using System.Text;

using System.IO;

using NationalInstruments.VisaNS;

using System.Threading;

 

namespace Example7

{

class Program

{

static void Main(string[] args)

{

//VXI-11 Connection string

string sAddress = "TCPIP0::10.0.1.196::INSTR";

//The VNA uses a message based session

MessageBasedSession mbSession = null;

//But we'll just open a generic Session first

Session mySession = null;

string responseStringN = null;

string[] splitN = null;

 

try

{

//open a Session to the VNA

mySession = ResourceManager.GetLocalManager().Open(sAddress);

//cast this to a message based session

mbSession = (MessageBasedSession)mySession;

 

//Timeout to 3 second (1000 ms)

mbSession.Timeout = 3000;

mbSession.TerminationCharacter = 0x0a;

mbSession.TerminationCharacterEnabled = false;

mbSession.SendEndEnabled = true;

 

//We'll limit the number of data points to keep buffer small

mbSession.DefaultBufferSize = 5000;

testClear(mbSession);

 

//Set the Language to NATIVE

mbSession.Write("LANG NATIVE\n");

mbSession.Write(":SENSE:SWEEP:POINTS 25\n");

//set format to Hz and Re/Im

//We set the format of the S2P file parameters to

mbSession.Write(":FORM:SNP:FREQ HZ\n");

mbSession.Write(":FORM:SNP:PAR REIM\n");

//Output S2P file over GPIB

mbSession.Write("TRS;WFS;OS2P\n");

responseStringN = testStatus_ReadArb(mbSession);

//the results are delimited by a newline (\n)

splitN = responseStringN.Split('\n');

 

//Send results to a file

StreamWriter output = new StreamWriter("VS_S2P.s2p");

foreach (string s in splitN)

output.WriteLine(s);

output.Close();

mbSession.Write("RTL\n");

mbSession.Dispose();

}

catch (VisaException v_exp)

{

Console.WriteLine("Visa caught an error!!");

Console.WriteLine(v_exp.Message);

}

 

catch (Exception exp)

{

Console.WriteLine("Something didn't work!!");

Console.WriteLine(exp.Message);

}

}

 

private static void testClear(MessageBasedSession mbSession)

{

mbSession.Write("*CLS\n");

}

 

private static string testStatus_ReadArb(MessageBasedSession mbSession)

{

//These are the bits to check

int b2 = 4, //Error Queue is not empty

b4 = 16; //MAV = Message Available

string responseString = null;

string replyString = null;

string errorString = null;

 

//Read the Status Byte of Service Request Status Register

StatusByteFlags sb = mbSession.ReadStatusByte();

 

while (((int)sb & (b2 + b4)) == 0)

{

Thread.Sleep(10);

sb = mbSession.ReadStatusByte();

}

if (((int)sb & b2) != 0)

{

errorString = mbSession.Query("OGE\n");

Console.WriteLine("Error Queue: " + errorString);

 

}

else if (((int)sb & b4) != 0)

{

responseString = mbSession.ReadString();

replyString = stripHeader(responseString);

}

mbSession.Write("*CLS\n");

return replyString;

}

 

private static string stripHeader(string responseString)

{

int i = 0;

string strReturn = null;

if (responseString[i++] == '#')

{

//Header is ASCII, get 2nd byte and convert to int.

StringBuilder sCount = new StringBuilder(responseString, i++, 1, 1);

int count1 = int.Parse(sCount.ToString());

//Now read the bytecount string and convert to int.

StringBuilder sBytes = new StringBuilder(responseString, i, count1, count1);

int count2 = int.Parse(sBytes.ToString());

//Set the index of the start of the data.

i += count1;

//return the string with the header stripped off

strReturn = responseString.Substring(i);

}

return strReturn;

}

}

}