How to use USB to control YOKOGAWA AQ7280

[zg0803]

If I use the AQ7280 usb drive (like picture 2) or use the NI-VISA Drive Wizard (like picture 4), the MAX also can not find the usb devices. 

Thank you

[rolfk]

Well USB is not a communication standard in itself, it's just the electrical connectivity between two devices much like Ethernet. What goes over the cable can be very different depending on the device.

When using the VISA driver wizard, it will create an USB raw device that you then have to program on lowest level. You only can do that with a programming reference manual that details the exact low level USB protocol, which for many devices is a carefully guarded trade secret.

With the Yokogawa driver the device is presented to the OS as one of many different device classes. VISA only can recognize and use USB-COMM (virtual serial port devices) and USB-TMC (Test and Measurement Class) device, but there are virtually several dozen other device classes and then a manufacturer is always able to define its own private device profile that only he alone knows how to interface to.