01-19-2024 11:53 AM
IVI.VISA 5.11.0.0 Issue with Visual C# (and at least one other application that I am aware of)
When looking for USB devices with this driver, it appears to find instruments that are not connected to the PC and assumes they are valid. For example, when I connect a resource with this address: -> USB0::2391::22279::MY59002474::0::INSTR, it finds this: -> USB0::0x957::0x5707::MY59002474::INSTR . The device address is displayed in decimal on its front panel, and the driver finds it as hexadecimal. However, the decimal representation of the USB address is still stored on the system registry, and the VISA driver "sees" it even when the device is no longer connected. I have used two of these Keysight 33622A Function Generators, and with neither connected, the GlobalResourceManager.Find() method still sees these two devices by their decimal USB addresses. If one happens to be connected at the time, it will open a session via the decimal address as well as via the hexadecimal address.
Keysight software also sees both the decimal and hexadecimal addresses if an instrument is connected, and only decimal if it is not.
01-20-2024 01:37 PM
On a PC where both NI VISA and Keysight VISA (IO Libraries Suite) are installed, the Find function seems to detect duplicate USBTMC devices. (At that time, two forms will appear: decimal notation and hexadecimal notation)
Duplication will be resolved by deleting one VISA.
01-22-2024 09:45 AM
Interesting! For the moment I can get around it by "filtering" to look only for the hexadecimal. I'm not sure how widespread Keysight IO Libraries is going to be but that's good to know. Thanks for the response.