Riedel Panel GPIO

September 11, 2018 smcrew

The Problem

It all started several years ago. I was managing the communications on a UK music festival put on by a well known fruit company. This was a great time with lots of very creative people, both artistically and technically. To make it even more interesting, we were allowed to experiment, with in reason.

The lighting crew for this run had a rather interesting dynamic. There were two programmers, one lighting designer (LD) for the house, one lighting designer for TV, a dimmer op, follow spots, and graphics, all in no particular order. This was the normal crew or as I liked to call them, the home team. This didn’t account for any traveling LD’s that would come along with the main act each night.

For most of the thirty-something show nights of this festival, only the main acts would be traveling with an LD. The design of the lighting rig would have been advanced to the traveling LD by both our house and TV LD’s. For the most part, very few opening acts traveled with an LD. They would simply leave the lighting decisions up to our “home team”. Not to say that any of the main acts lighting looked bad, but the house lighting team had really learned their way around the rig by the end of the run.

Early on we found that the lighting department leads really needed two things; communication with each other and more hands.  We already had a Riedel Artist system in place, so there was plenty of communications horse power to go around. The second part was to make the comm system easier to use, preferably hands free.

Finding a Solution

After a quick visit to a local music store we had purchased a few keyboard sustain pedals. A little manual reading and soldering later we had a prototype. After some discussion with the LD’s, programmers, and graphics operator we figured out what buttons each used most that we could be transferred to a pedal.

GPIO and you

So what is this GPIO thing and what can it do for me? General Purpose Input Output is just like the name suggests. In it’s simplest form, the input is a sensor to trigger some function when is sees a small amount of voltage. The output is looking to send out a small amount of voltage to trigger some external device when commanded to do so. We can get creative and use these sensors to our advantage.


Once we have our interface, be it a button, or pedal, or some other device, now what? First thing is to open your version of Director and navigate to the panel you want to add an external control to.

Undefined GPIO

Next, right click on the “GPIO Ins” where it says “not defined”. A button will appear asking to “define GPIO”.







Defined GPIO

In this menu you’ll choose whether the GPIO should expect to see a normally open or normally closed circuit. This has to do with the switch you’re using and means when the button is in it’s normal state, not being triggered, is the circuit open or closed. Most of the time I use normally open switches, but it’s nice to have the option.






Programming like a normal key

Once you hit OK, you can program it like a normal key. In the case of my lighting department, they like to get their reply key, a lighting department all call, and a key to call the spots. With an Artist system, any key can be almost anything, so everyone can get what they want.


This setup proved to be very successful. So much in fact that the lighting gang would get bummed out when I told them they could only have three pedals each. Each year that we repeated the show I learned I needed to have more pedals with me and never had enough for everyone’s needs. It just went to show how valuable hands free communication was for some departments.

Comm Pedals