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c++windowsusb

Easiest way to control USB TMC device on Windows/C++

I am developing C++/Qt application which interacts with Tektronix TDS2002 oscilloscope via USB. The oscilloscope appears as "USB Test and Measurement device (IVI)".

Currently I use TekVISA library supplied by the oscilloscope's vendor. It works, but it is huge, old, buggy and poorly maintained. Therefore I would like to bypass the library and interface the device directly.

So far I have found this simple library: https://github.com/xyphro/WinUsbTmc It is exactly what I am looking for, but it uses libusb which requires to install some device filter and in addition it is advised to be more development tool than customer solution. Do you have any experience on this?

What is the easiest way to interact with USB Test and Measurement device in Windows/C++/Qt?

Thank you for your suggestions :)

Solution

    1. You need a USB driver. My oscilloscope works with the driver included in this VISA package (the driver can be extracted very easily): http://www.keysight.com/main/software.jspx?cc=CZ&lc=eng&nid=-11143.0.00&id=2504667&pageMode=CV I assume all USB TMC devices can use the same driver, but I have no possibility to check this.

    2. USB driver can be accessed via standard Windows functions. Guys on this forum were really close: https://forum.tek.com/viewtopic.php?f=568&t=137573 and also this document was very useful: http://www.ivifoundation.org/downloads/Class%20Specifications/Ivi-6%202_USBTMC_2010-03-23.doc

    3. You cannot write commands to OSC directly - data you send and receive have certain header which has to be in the correct format, otherwise the oscilloscope ignores the message. See reading and writting implementation in this simple library: https://github.com/xyphro/WinUsbTmc I didn't use this library because it uses libusb library which uses some kind of device filter and I personally do not like this concept (and in addition I have genuine working driver).

    4. Data you read have also a simple header. To ensure you fit the header structure on input data well, you should first flush the input buffer. Then you issue reading request (using write command - see WinUsbTmc library above) and finally you receive the data and fit the header on its beginning.

    I hope this will help to somebody :)

    With regards

    klasyc

    EDIT: You can check my ScpiNet library, which implements the instructions above in C#.