NI-VISA

[jgent]

Oke I didn't know that. I thought RS-232 are the old cables (https://en.wikipedia.org/wiki/RS-232). Anyhow, I am not sure how to check what kind of adapter I have, can you tell me how? If this helps, I am trying to use the USB ports of my laptop. I use a Lenovo TP X1 Extr. G3 i7 32GB/1TB LTE 4K.

[jgent]

I got the laptop from here:

https://www.arp.ch/en/lenovo-tp-x1-extr-g3-i7-32gb-1tb-lte-4k-20tk002umz-5488520-40

[pincpanter]

The focus should be more on the device you connect to the USB (and possibly to the OS you are using), not on the USB itself.

[rolfk]

As Paolo already mentioned, the USB port and therefore the laptop you use is pretty much irrelevant. (It could have an influence but then you would likely see other problems with other USB devices too). The interesting aspect is your device that you connect to the USB port, be it an explicit adapter or a device with USB port that implements an USB-CDC (COMM) device class. 

[jgent]

Oke I can check the device's specification tomorow. Altought, I dont think this is the problem since, the usb can not be accessed via NI MAX with the VISA test panel, no mather if the device is connected or not. I also tried to use a different IMU sensor. I had the same problem.

It used to work on an different Laptop with Windows 7. I am currently using Windows 10.

On the old Laptop I could access the USB port via VISA test panel in NI MAX. It didn't matter if a device was pluged in or not.

[rolfk]

That definitely makes no sense. USB devices are Plug and Play devices. They are only present in a system when plugged in!

what you describe sounds more like a special driver that can be installed under windows and installs a static device that then translates the serial port commands into whatever the actual device needs (likely a proprietary USB protocol). Sounds like a roundabout way to go about this but I have seen stranger things. This special driver hasn’t been (correctly) installed on your Windows system, or it’s not Windows 10 compatible. Windows 10 requires device drivers to be signed in order to allow installation of them, so maybe that is your problem.

[jgent]

So how do I solve this? Do I have to update the USB port drivers? It tells me that I have the most recent version installed.

Is there some dummy device that I can use as a plug an play and test if VISA works there? I have tried to plug in USB memory sticks and File Explorer recognises them but NI VISA can't access them.

[billko]

At this point, I have no idea what is going on here.  Is it even supposed to show up as a COM port?

[DavidBoyd]

It might be very helpful, at this point, to open Windows Device Manager, expand the section where your device is located (is it even "Ports"?), open the device's "Properties" dialog, choose the "Details" tab, select "Hardware IDs", and post that back to this group.  The vendor and device IDs would be critical for us to know, to offer further suggestions.  Actually, info on the loaded driver would be important, too.

Dave

[rolfk]

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@jgent wrote:

So how do I solve this? Do I have to update the USB port drivers? It tells me that I have the most recent version installed.

Is there some dummy device that I can use as a plug an play and test if VISA works there? I have tried to plug in USB memory sticks and File Explorer recognises them but NI VISA can't access them.

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You clearly have not a good idea what USB means.

Imagine people talking. USB is the air and the sound vibrations of speech that are transported through it. But some people talk English, others French and some more Chinese. They all use the same medium (air) to transport the speech over, but they do not understand each other. This is the same with USB.

USB is the cable and basic protocol in how the bits and bytes are transported over it. But there are many different languages. One is called USB-HID (Human Interface Device) which is used by keyboards, mice and joysticks. Another is USB-MSC (Mass Storage Class) which is used by your USB memory stick. Then you have USB-CDC (Communication Device Class) which is usually used for RS-232 virtual ports. Then there is USB-TMC (Test & Measurement Class) which is similar to CDC but specifically for measurement devices with extra IEEE-488.2 compatibility.

NI-VISA only can talk USB-CDC (through the OS native COMM port API) and USB-TMC. All other USB languages are for NI-VISA simply Greek! So you can plug in 500 USB memory sticks if you want but NI-VISA can't do anything with them. Neither can it do anything with keyboards, mice, cameras, your audio speaker or anything else you can connect to USB unless it is an USB-TMC device or an USB virtual COMM device.