VISA is an acronym that stands for Virtual Instrument Software Architecture. In a nutshell, VISA handles the communications between your computer’s OS and the instrument.  You may be familiar with TekVISA, which is Tektronix’s own brand of VISA. Agilent and National Instruments also have their own VISA’s. Each VISA is comprised of a communications driver, a USBTMC driver (USB Test and Measurement Class driver), a VISA software library and documentation, an instrument connection manager, an instrument communication tool, and an instrument communication logger. All of these individual pieces enable users to interface between computers and instruments using various protocols including USB, GPIB, Ethernet/VXI-11/Raw Socket, or RS-232. Let’s dig into the VISA interface. In order to do that, you’ll need to download and install TekVISA from our website. Find the latest software version right here . Once you’ve got everything downloaded and installed, we can see how it all works together. TekVISA is accessed through the OpenChoice Instrument Manager software, so go ahead and launch that to get started. The interface is fairly simple, but there are a few panels and buttons to get acquainted with. The Instruments panel on the left shows a list of all the instruments that are connected and available, and the Applications and Utilities panel on the right lists the instrument communication tool (OpenChoice Talker-Listener) and the instrument communication logger (OpenChoice Call Monitor). The Instruments panel has 4 buttons on the bottom: Update…, which refreshes the instrument list and searches for new instruments connected to your computer, Search Criteria…, which allows you to set up the criteria that OpenChoice uses to look for instruments, Identify…, which identifies the selected instrument using a programming query, and Properties…, which lists out the properties of the selected instrument. For this example, I’ll be using an MDO4105-6 and I’ll be connecting via USB and Ethernet.  Connect the A/host end of the USB cable to your computer and the B/device end to your scope. Go to the Search Criteria Menu in OpenChoice Instrument Manager. Select USB and make sure it is activated, click OK, and click Update on the main panel. The instrument should show up in the Instrument List Panel if it’s not already there. Select it and click Identify. A small window will pop up and identify the instrument, giving its model and serial number. If you click on Properties, you can see the address of your instrument and give it a custom name if you like. Similarly to connect via LAN, plug an Ethernet cable into the LAN port on the scope and connect the other end to a distribution device such as a router that is also connected to the same network as your computer. You will need to know the IP address of your scope, and there is a separate video that explains how to set up a network connection on the MDO. After you’ve determined the scope’s IP address, go to the Search Criteria menu in OpenChoice Instrument Manager, select LAN, make sure the Search LAN checkbox is marked, enter the IP address of your scope into the Hostname field and click the down arrow below the field. Select the instrument that comes up in the list and click search. This will cause it to appear in the Instruments panel on the left. Again you can use Identify… and Properties the same way you can with a USB device. <![CDATA[/* > <!]]>*/
YouTube Part 1/3: http://youtu.be/ob1wTNI0tnw YouTube Part 2/3: http://youtu.be/38Q4eCcZv-8 YouTube Part 3/3: http://youtu.be/0FZ6DXP6USE FAQ Part 1: /support/faqs/what-tekvisa-and-how-can-i-use-it-communicate-and-control-my-instrument FAQ Part 2: /support/faqs/how-do-i-use-tekvisa-send-commands-my-instrument FAQ Part 3: /support/faqs/how-do-i-use-programmer-manual-my-instrument