marcopashkov / canon-diy-remote-control

how to hack your triggertrap mobile dongle to work with an arduino

Canon DIY remote control

How to hack your triggertrap mobile dongle to work with an Arduino

This github-repository contains everything you need to connect your Triggertrap-mobile-dongle to an Arduino. Even if you do not have the Trigger-trap you find all information to either build your own, or how to at least easily trigger your camera with a simple button.

I have been using this setup on my Canon 5D Mark III and it works just fine.

Table of Contents

• Shopping List
• Wiring
• What I learned
  • Audio jack
  • Camera connector
  • How to trigger your camera without a triggertrap
• Ressources

Shopping List

1. Arduino Leonardo
2. Triggertrap mobile kit - (Amazon US)
3. TRRS 3.5mm Jack
4. Cables (3x)
5. Breadboard

Wiring

The wiring is very simple.

1. Arduino pin 3 to Audio-Jack Tip
2. Arduino pin 5 to Audio-Jack Ring 1
3. Arduino ground to Audio-Jack Ring 2 or Sleeve

What I learned

Audio jack

Camera connector

This is only interesting to you if you actually plan to build your own trigger-trap contraption. In this case you might want to actually read this article, as all you need is a button. Meaning: The camera outputs a 1V charge on its shutter-pin and focus-pin. If you ground either of them via the ground-pin you can trigger either action.(see the image below for the 3 pins)

The tricky part is now figuring out how the trigger-trap works internally, so you can hook it up to the Arduino. It turns out that the Trigger-trap uses two transistors to ground the contacts(more info). So you need to apply a charge to the camera connector in order to open the transistor(-switch). However, since the Trigger-trap is supposed to work with iPhones it does not accept a simple DC-charge. You actually need AC for this! Luckily the Arduino can fake AC-charge somewhat with it's PWM-pins. All you need to do is use the Arduinos analogWrite-function.

How to trigger your camera without a triggertrap

If you have a cable that fits into the Camera-remote-trigger port(e.g.: this one) just ground the 2.5mm audio-jack tip with the ground and the camera should get triggered.

This is the Input Serial Pullup concept, which is a very neat way of implementing a button.

Ressources

How the canon remote controller-jack works.
How the trigger-trap mobile dongle works.
iPhone auxiliary uses AC instead of DC.
Fritzing - a great tool for circuit designs - from Potdam, Germany :-).