Official Firmware for the Timelapse+ Intervalometer
avr-gcc
dfu-programmer
libusb
Mac users: do not use the CrossPack installer -- it's broken and won't work with this firmware. Instead, use homebrew with this formula: http://github.com/larsimmisch/homebrew-avr
First, connect the Timelapse+ device via USB and boot in DFU mode (hold top two buttons and press the down button, red light will blink). Then, run the following two commands in the project folder:
make
make dfu