3. visa and visa tools -ag真人试玩网址
at the time, where gpib was the main physical communication interface, remote control applications communicated directly with gpib hardware drivers. then, the rs232 serial interface was introduced as a cheaper alternative to gpib. also here, applications communicated directly with the rs232 hardware drivers.
the situation got even more complex as lan interface has become the standard in the computer industry. test & measurement instrument vendors have foreseen the potential lan interface can bring to connectivity options for their instruments. however, using a third software interface for the lan-connected instruments would bring more complexity to test and measurement applications.
out of the motivation to unify the software interface, vxiplug&play alliance introduced visa standard (virtual instrument software architecture). currently, the maintanance of visa is done by the ivi foundation. for the lan interface, the tcp/ip-based protocol was named vxi-11. later, came its improved version called hislip. the last addition was support for the usb interface. the usb class of devices natively supported by visa are called usb-tmc (test and measurement class).