DIY Canon IR Remote

Story

Introduction

Canon SLR cameras have two ways of remote triggering: Either via wire, or via infrared.
A wire based remote trigger is very easy to build, you simply need a cable with a 2.5″ jack connector and shortcut two of the three contacts. More details on blog.dbrgn.ch.
The other method – triggering via infrared – is a bit more challenging. There are a lot of cheap remote controls from China for around 10$, but building your own remote is muc more interesting…
First you need to find out how the protocol for the IR control works. Fortunately there’s a post on doc-diy.net that describes the RC-1 protocol in detail. Summary: Send two bursts of 16 pulses each and get the timing right.

Casing

The casing was created using OpenSCAD and can be printed on a 3D printer. It is based on a Design by Ted Lin. The sourcecode for the case is on Github and Thingiverse.

Software

The Atmel C code for the ATtiny is quite simple. In the main function first the I/O is initialized:

// Set up I/O
DDRB = _BV(PB1) | _BV(PB2) | _BV(PB4); // PB0 is input, PB1/2/4 are output
PORTB = _BV(PB0); // Pull-up for input PB0

Then unnecessary features of the microcontroller are disabled to save energy.
For more detail: DIY Canon IR Remote