Needs["NETLink`"]

lib = LoadCOMTypeLibrary[
"C:\Program Files (x86)\IVI Foundation\VISA\VisaCom\GlobMgr.dll"]
mgr = NETNew["Ivi.Visa.Interop.ResourceManagerClass"];
OSA = NETNew["Ivi.Visa.Interop.FormattedIO488Class"];

devs = mgr@FindRsrc["?*instr"];
devdescr = {};
Do[
OSA@IO = mgr@Open[devs[[i]]];
OSA@WriteString ["*IDN?"];
id = OSA@ReadList[];
AppendTo[devdescr, id[[2]]],
{i, 1, Length[devs]}];

If[devs == $Failed, devs = {"empty"}; devdescr = {"NoDeviceDetected"}];

OSA@IO = mgr@Open[devs[[x]]]

OSA@WriteString ["<command>"]

OSA@ReadList[]

OSA@ReadString[]