How to Control Your Instruments From A Computer: It’s Easier Than You Think

There was a time when instruments sporting a GPIB connector (General Purpose Interface Bus) for computer control on their back panels were expensive and exotic devices, unlikely to be found on the bench of a hardware hacker. Your employer or university would have had them, but you’d have been more likely to own an all-analogue bench that would have been familiar to your parents’ generation.

A GPIB/IEEE488 plug. Alkamid [CC BY-SA 3.], via Wikimedia Commons
A GPIB/IEEE488 plug. Alkamid [CC BY-SA 3.], via Wikimedia Commons.
The affordable instruments in front of you today may not have a physical GPIB port, but the chances are they will have a USB port or even Ethernet over which you can exert the same control. The manufacturer will provide some software to allow you to use it, but if it doesn’t cost anything you’ll be lucky if it is either any good, or available for a platform other than Microsoft Windows.

So there you are, with an instrument that speaks a fully documented protocol through a physical interface you have plenty of spare sockets for, but if you’re a Linux user and especially if you don’t have an x86 processor, you’re a bit out of luck on the software front. Surely there must be a way to make your computer talk to it!

Let’s give it a try — I’ll be using a Linux machine and a popular brand of oscilloscope but the technique is widely applicable.

Continue reading “How to Control Your Instruments From A Computer: It’s Easier Than You Think”