avrdude with a Linux SPI programmer type, customized for flashing pisound firmware by BlokasLabs.
Run the following commands in a terminal:
git clone https://github.com/BlokasLabs/avrdude.git
cd avrdude
./install.sh
Run in a terminal:
avrdude --version
Expect to see the following output at the bottom:
avrdude version 6.1-svn-20130917-blokas, URL: <http://savannah.nongnu.org/projects/avrdude/>
Kevin Cuzner Jun 2013 kevin@kevincuzner.com
Using baud-rate to control SPI frequency
Rui Azevedo (neu-rah) Jun 2013 ruihfazevedo[arroba]gmail.com