Hi,
I am setting the DefaultBufferSize parameter before sending the data.
I've tried to send the data in smaller packets but once again the overall time is nearly the same:
Sending data size of 32 MB in packets of 512 bytes take 41.19 seconds.
Sending data size of 32 MB in packets of 32768 bytes take 41.03 seconds.
Sending data size of 32 MB in packets of 131072 bytes take 40.92 seconds.
My code:
Stopwatch sw = Stopwatch.StartNew();
int NumOfDigits = 0;
byte[] sendArray;
string ResponseString = null;
try
{
//open a Session to the VNA
MbUnitSession = ( MessageBasedSession )ResourceManager.GetLocalManager().Open( UnitAddress );
Thread.Sleep( 100 );
// init mbUnitSession
MbUnitSession.Timeout = 15000;
MbUnitSession.SendEndEnabled = true;
MbUnitSession.TerminationCharacterEnabled = true;
MbUnitSession.DefaultBufferSize = Globals.BUFFER_SIZE; // buffer size is 32768
//** communication with device **//
//Send "*IDN?" command and read the response
ResponseString = WriteToVisa( MbUnitSession, "*IDN?" );
//Send "*rst" command
WriteToVisa( MbUnitSession, "*RST" );
Thread.Sleep( 1000 );
int s = Globals.CurrentWaveLength * 2; // waveLength is 32000000
WriteToVisa( MbUnitSession, ":FREQ:RAST" + "1e9" );
ResponseString = WriteToVisa( MbUnitSession, ":FREQ:RAST?" );
// Select User (Arbitrary Wave) Mode
WriteToVisa( MbUnitSession, ":FUNC:MODE USER" );
// Delete all segments
WriteToVisa( MbUnitSession, ":TRAC:DEL:ALL" );
// Define segment + select segment 1
string msg = ":TRAC:DEF 1," + Globals.CurrentWaveLength + ";:TRAC:SEL 1;";
ResponseString = WriteToVisa( MbUnitSession, msg );
// set new timeout
MbUnitSession.Timeout = Globals.CurrentWaveLength;
NumOfDigits = Convert.ToInt32( Math.Floor( Math.Log10( s ) + 1 ) );
WriteToVisaNoOPC( MbUnitSession, ":TRAC:DATA#" + NumOfDigits + ( s ) );
int arrSize = Globals.ByteArray.Count(); // ByteArray contain the bytes to send to the unit, size is 64000000
// loop that sends chunks of the array in the size of the buffer
for( int i = 0; i < Globals.ByteArray.Count(); i += Globals.BUFFER_SIZE )
{
if( arrSize >= Globals.BUFFER_SIZE )
{
sendArray = new byte[Globals.BUFFER_SIZE];
Buffer.BlockCopy( Globals.ByteArray, i, sendArray, 0, Globals.BUFFER_SIZE );
arrSize -= Globals.BUFFER_SIZE;
}
else
{
sendArray = new byte[arrSize];
Buffer.BlockCopy( Globals.ByteArray, i, sendArray, 0, arrSize );
}
//Write Binary Data
WriteToVisaByteArray( MbUnitSession, sendArray );
}
// select channel 1 + turn channel 1 outputs on
ResponseString = WriteToVisa( MbUnitSession, ":INST:SEL 1;:OUTP ON" );
// set amplitude
WriteToVisa( MbUnitSession, ":VOLT 2.000e0" );
// set selected channel on
WriteToVisa( MbUnitSession, "outp on" );
MbUnitSession.Dispose();
if( showTime == true )
{
// display the time it takes to download the data to the unit
MessageBox.Show( "Download time is: {0:f2} s" + sw.Elapsed.TotalSeconds );
}
}
catch( InvalidCastException )
{
MbUnitSession.Dispose();
}
catch( Exception )
{
MbUnitSession.Dispose();
}
WriteToVisa is a function that sends a string to the unit with "*OPC?" command and return a response.
WriteToVisaNoOPC is a function that sends a string to the unit without "*OPC?" command and return a response.
WriteToVisaByteArray is a function that sends a byte array to the unit and not return anything.
Thank you for all your help.
