Understanding GPIB

[@chitol1]

This is a great video. I can't believe that you guys are making a video on GPIB after it has been around for more than 30 years

[@pauldenisowski]

Thanks! GPIB is still an important technology - many of our customers still use GPIB and even our newest instruments have GPIB as an option. And a knowledge of GPIB is helpful for understanding SCPI (which I'm covering in an upcoming video)

[@xDevscom_EE]

GPIB is excellent interface for low speed communications even today as it does not require additional hardware to daisy-chain many instruments together, unlike LAN/USB/Serial. It's also widely supported by industry and easy to work with after you setup the GPIB host/controller properly.

[@Floyd..B]

These videos are pure knowledge, thank you for making so many of them. What kind of software do you use to make the graphics ?

[@pauldenisowski]

Thanks for the kind feedback! Since the presentations are animated PowerPoint, I make most of the simple graphics directly within PowerPoint -- I think many people underestimate just how flexible the PowerPoint drawing tools are. For more complicated things, I use Adobe Illustrator, and most of the measurement results (traces) are exported MATLAB plots of saved measurements I've made.

[@Floyd..B]

​@@pauldenisowski Thank you, I'm using Inkscape for the moment (still learning to do vector graphics). I will try the PowerPoint drawing tools more extensively next time I use them.

[@fly_raptor_1014]

Nice video! Could anyone provide the link for the "Understanding SCPI" video mentioned at 0:16?

[@pauldenisowski]

I'm still working on it :) I'm hoping to have it done in the next couple of weeks, so please stay tuned!

[@jesperbjorklund4713]

13:05 Why do the NRFD and NDAC lines only become un-asserted after all listeners have un-asserted it? Does un-asserted = logical 0 in this exampel? How would the talker determine that all devices have un-asserted if the voltage on the line equals high as soon as the first listener un-asserts? Then there would be no difference between all un-asserted and only one un-asserted

[@pauldenisowski]

That’s a great question. GPIB implements NRFD and NDAC using what’s called a “wired or” concept in which the lines are driven with open collectors. A line is low (true) when any single device pulls it low, even if other devices on the line are trying to pull it high.

[@pragadeeshwaranuk2050]

Could you please add the link for "Understanding SCPI"

[@pauldenisowski]

I’m still working on it :). It should be posted in a few weeks or so.

[@technical5880]

thank you.

[@pauldenisowski]

Thanks for watching!