Saturday, April 28, 2012

Video Blog Episode #14 - Audio Based Trigger

In this episode I show off my first electronics project I made just over 1 year ago. The concept was to trigger a separate circuit (such as the shutter of a DSLR camera) using audio.

Saturday, April 21, 2012


[UPDATE] You can find this GPIBUSB adapter on my store at !

[UPDATE Jan 11, 2014] Revision 3 is now available for purchase at

Hello everyone! It's been about 3 weeks since my last post, and about 2 weeks since my last video. One may ask, what's the holdup for everything Steven? Well, part of it was me forgetting to post the latest episode here.


What was this video about? Well, my GPIBUSB adapter is for sale! Now, some of you may be visiting my blog for the first time and have no idea what this GPIBUSB thinger is. Fear not, allow me to introduce to project to you!

My GPIBUSB is an open source hardware project that allows the user to connect test and measurement instruments featuring a GPIB (aka HPIB, ieee488) port to a computer's USB port. This allows the user to remotely control their T&M instruments from their computer!

Now, before we go any further, I'm sure some of you would like to see the source files. You can find everything at


The adapter utilizes a PIC18F4520 microcontroller, and a FT232RL to convert from USB->UART. This means that the GPIBUSB presents itself to one's computer as a serial port, giving you the freedom to use a wide variety of operating systems and programming languages with minimal setup.

One could use this adapter for automated tests. For example, you could log power consumption of your device under test by using this adapter to transfer voltage and current measurement from attached DMMs. Another example could include transferring waveform data from one's oscilloscope to your computer to do further analysis.

GPIBUSB in action in the UK!

And of course, the PCB is made in Canada. All assembly is done by myself, also located in Canada.

Now, for those that are interested in ordering one. At the time of writing, I have 8 adapters all assembled and tested, with parts for another 10 on my bench. Cost is $60 CAD plus shipping. If you are from Canada, add 13% for HST. For shipping, options are either FedEx (both ground and express) or Canada Post. An exact number will be given after you contact me and let me know what shipping method you would like.

Payment is through Paypal.

If you are interested, please email me at scasagrande at galvant dot ca.

Thanks everyone for supporting me, my new business (Galvant Industries), and OSHW!

  • Connect your computer to your instruments' GPIB port by USB
  • USB-B connector
  • Cross platform - works on Windows, Linux, and OSX
  • Cross language - works with any programming language able to connect to serial ports
  • Includes pre-written python classes for easy communication with instruments
  • Upgradeable firmware - Useful to add new features and bug fixes easily
  • Both assembled and PCB manufactured in Canada

Items of note:
  • Currently does not support service request. Will be added at a later date.
  • Contains lead (Pb). Soldering was done using 63/37 solder.
  • All source can be found at
  • Does not include USB cable