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Set Up Fast CW and FIFO

This example program does the following:

IMPORTANT - Because the IFBW is set to 600 kHz, data will NOT be sent to the FIFO after each acquisition. Learn more.

The SCPI commands in this example are sent over a COM interface using the SCPIStringParser object. You do NOT need a GPIB connection to run this example.

This VBScript (*.vbs) program can be run as a macro in the VNA. To do this, copy the following code into a text editor file such as Notepad and save it on the VNA hard drive as FIFO.vbs.  Learn how to setup and run the macro.

See the SCPI FIFO commands.

See Other SCPI Example Programs

Dim returnStr

Dim app

Dim p

Dim start

Dim complete

Dim init

Dim finished

' Create / Get the VNA application.

Set app = CreateObject("AgilentPNA835x.Application")

Set p = app.ScpiStringParser

sub Write (command)

if len(returnStr) <> 0 then

err.Raise 55,"Write","Query Unterminated"

end if

returnStr = p.parse(command)

end sub

'

sub WriteIgnoreError(command)

returnStr = p.Execute(command)

p.Parse("SYST:ERR?") ' clear error queue

end sub

'

function Read

if len(returnStr) = 0 then

err.Raise 55,"Read","Bad read"

end if

Read = returnStr

returnStr = ""

end function

' Setup and measure A/R and B/R

Write "SYST:FPRESET"

Write "DISP:WIND ON"

Write "CALC:PAR:DEF:EXT 'meas1','A/R1,0'"

Write "DISP:WIND:TRACE:FEED 'meas1'"

Write "CALC:PAR:DEF:EXT 'meas2','B/R1,0'"

Write "DISP:WIND:TRACE2:FEED 'meas2'"

' Set IFBW to 600 khz (400 thousand pts/second)

Write "SENS:BWID:RES 600khz"

' Point Averaging Count = 1

Write "SENS:AVER:MODE POINT"

Write "SENS:AVER ON"

Write "SENS:AVER:COUNT 1"

' Edge triggering - positive edge

'Write "CONT:SIGN BNC1,TIEPOSITIVE"

'Write "TRIG:SOUR EXT"

'Write "SENS:SWE:TRIG:POIN ON"

' Setup FIFO and Fast CW count

Write "SENS:SWE:MODE HOLD"

Write "SYST:FIFO ON"

Write "SYST:FIFO:DATA:CLEAR"

Write "SENS:SWE:TYPE CW"

Write "SENS:SWE:TYPE:FACW 1000000"' set the point count to 1 million

Write "SENS:SWE:MODE SING" ' start an asynchronous acquisition.

init = now()

' Gather data

'wait until end of sweep. Timeout needs to be very large here.

Write "*OPC?" '

opcCount = Read()

Dim points

Write "SYST:FIFO:DATA:COUNT?"

points = Read()

msgbox points

' points == 2000000 ' points = 2million. Took 5 seconds to acquire

For I = 0 to 1 ' 2 iterations (2 parameters * 2 sets of 1 million)

Dim data

Write "SYST:FIFO:DATA? 1000000"

Data = Read()

Next

'turn FIFO and FastCW OFF

Write "SYST:FIFO OFF"

Write "SENS:SWE:TYPE:FACW 0"

 

finished = now()

msgbox "Init ="  & init & vbCrLf & "Done ="& finished