find hardware lists devices not connected

[Jim_Marihew]

When using the Find Hardware VI, it reports devices that are no longer connected (as does Max).  Even using the IsPresent property, the response is yes.  If I try to open a VISA connection to query it for confirmation of its presence I get an error dialog.  Is there a way to find out which devices are actually connected without generating an error?

[Bob_Schor]

You realize, don't you, that you answered your own question.  Suppose you have an array of "All Devices".  Put this Array through a For loop (which gives you the devices "one-at-a-time") and try to access the device.  If you get an Error (because the devices really isn't there), wire a False to the Conditional input of the Output Auto-indexed Tunnel (right-click the Tunnel and make sure that "Conditional" is checked).

Bob Schor

[Jim_Marihew]

Hi Bob.  I'm trying to make the search for the instrument transparent to the user.  I don't want the error dialog to pop up.

[crossrulz]

---

@Jim_Marihew wrote:

Hi Bob.  I'm trying to make the search for the instrument transparent to the user.  I don't want the error dialog to pop up.

---

Then handle the error so the dialog does not pop up.  Even wiring it up to a Not will work.  The result of that Not can then be used with a conditional indexing tunnel to only keep the valid references.

[Jim_Marihew · Accepted solution]

DOH!  I had an error handler, but forgot to wire the "no dialog" to it. 😳

[BertMcMahan]

"Clear Errors" also works. Or, set your VI's to not automatically handle errors (File -> Properties -> Execution, IIRC).