Instrument Control (GPIB, Serial, VISA, IVI)
Using Excel VBA (VisaComLib or VisaCom) to Connect to a Keysight LCR Meter
Goal: I have a Keysight E4980AL LCR meter that I am trying to get to read and record data onto an Excel spreadsheet.
The instrument in question.
I need to do this using VBA (Visual Basic for Applications) in Excel because this is what my organization uses. The LCR meter is connected to my workstation using a GPIB-to-USB interface cable. I have the latest Keysight IO Library Suite installed (downloaded from here: https://www.keysight.com/us/en/lib/software-detail/computer-software/io-libraries-suite-downloads-21...), and the LCR meter is showing up under "Connection Expect" and displaying no issues. Finally, I have VISA-COM 5.14 Type Library enabled under Tools > References. Everything sounds good and well (at least so far).
Lord, you will not believe the trouble I am having. I have already tried 2 workarounds, one of them got me closer than the other, but nothing performed the original goal/intent that I set out to do. Allow me to explain each alternative I have tried so far, and how far I've gotten below:
Solution 1 (Keysight IO Library Suite) - NOT GOOD. BLOCKED
As mentioned previously, I downloaded and installed Keysight's IO Library Suite, and created a test program to try to query the instrument and display a message.
Unfortunately, when I run my VBA test code, I get the following error message from Excel: "A connect error occurred: HRESULT = 80040011". The error message.
The actual error returned is "HRESULT = 80040011". The rest is from my test code.
I did some digging around on Microsoft's error page and found that code 80040011 meant that Excel was not able to convert the object in question.
Error code on Excel's error page
I did a whole bunch of F8's (debugging by stepping into the code) and pinpointed the error to this line:
`Set session = ioMgr.Open(resourceString)`
Here is the full code that I am testing and running into the error message in:
```
Option Explicit
Private Declare PtrSafe Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As LongPtr)
Public Sub connect()
Dim ioMgr As VisaComLib.ResourceManager
Dim instrAny As VisaComLib.FormattedIO488
Dim resourceString As String
Dim session As VisaComLib.IMessage
Dim id As String
Dim value As Variant
' address of instrument
resourceString = "GPIB0::17::INSTR"
vba_version = "8" 'vba version
On Error GoTo ioError
Set ioMgr = New VisaComLib.ResourceManager
Set session = ioMgr.Open(resourceString)
session.WriteString "*IDN?" & vbLf
id = session.ReadString
MsgBox "Connected to " & instrQuery & vbCrLf & "VBA version:" & vba_version & vbCrLf & "Interface:" & InterfaceIndex
Exit Sub
ioError:
MsgBox "A connect error occured:" & vbCrLf & Err.Description & vbCrLf & "Interface:" & InterfaceIndex & vbCrLf & "VBA version:" & vba_version
End Sub
```
So, when I run this `connect()` macro, the earlier error message comes up. I want the actual result to be the MsgBox message.
Solution 2 (Using NI VISA) - MORE PROGRESS, BUT MISSING FUNCTIONS
I downloaded some sample programs for the E4980A from Keysight's website (https://www.keysight.com/us/en/lib/software-detail/programming-examples/sample-programs-for-the-e498...), and it appears that they are using NI's VISA implementation. So I finally downloaded NI VISA and tried using that instead (https://www.ni.com/en/support/downloads/drivers/download.ni-visa.html?srsltid=AfmBOoqO_91KlqcDIt8AVw...). I still ran into some issues, but running the sample program, I at least was able to read something from my meter. This prompted me to try rewriting my program using NI VISA. I set NI VISA to be the primary VISA implementation, but when I run my test code, VBA for some reason does not recognize `viVPrintf` functions. I noticed that my project files didn't contain the VISA32 modules that came with the sample code, and so I suspect that might have something to do with VBA not recognizing my functions. My question is, do I need to provide this VISA32 module in all future VBA projects?
I will have more details to upload tomorrow.
I'm using `VisaComLib` in the first solution. I am not experienced with `VisaComLib` or Keysight's product line at all, which is why I suspect there's either a deeper issue here or something super obvious that I just completely overlooked. I don't have enough knowledge about VBA or `VisaComLib` to troubleshoot/debug this. If someone knows what is causing this error, a possible workaround, or how to fix this, they will share my eternal gratitude. I have been stuck on this for close to a month now.
I am more than happy to answer any questions or test anything. Please help. Thanks.
