Notes from Prototype Radio

The original prototype works, but did several things differently. To help the development process for the newer version(s), here are some notes from the original.

Audio Hardware

The original uses a USB audio sound card.

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 1: ATR2USB [ATR2USB], device 0: USB Audio [USB Audio]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
rmann@arm:~$ aplay -L
null
	Discard all samples (playback) or generate zero samples (capture)
sysdefault:CARD=ATR2USB
	ATR2USB, USB Audio
	Default Audio Device
front:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	Front speakers
surround40:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	4.0 Surround output to Front and Rear speakers
surround41:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	4.1 Surround output to Front, Rear and Subwoofer speakers
surround50:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	5.0 Surround output to Front, Center and Rear speakers
surround51:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	5.1 Surround output to Front, Center, Rear and Subwoofer speakers
surround71:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	7.1 Surround output to Front, Center, Side, Rear and Woofer speakers
iec958:CARD=ATR2USB,DEV=0
	ATR2USB, USB Audio
	IEC958 (S/PDIF) Digital Audio Output