Page 2 of 6
Our board came in a small unprepossessing cardboard box, together with two support pillars and nylon attachment screws. It’s multi-pin connector is a simple push fit onto a matching connector on the Raspberry Pi board. Easy and trouble free – no soldering is needed.
Software for the board, including music player and audio drivers, must be installed. This isn’t quite so easy; see our accompanying article on the Raspberry Pi computer; Douglas wasn’t always so happy about difficulties here! You have to be aware that you must save an image that is bootable, meaning it must be seen directly by the bios – and not a file buried in a file tree structure.
Audio input and output sockets are all fitted: phono sockets and 3.5mm stereo jacks.
On the underside lies a long black connecting block that simply plugs into the Raspberry Pi board.
BOARD SET UP
The WM5102 uses a bus switching system known as ALSA, to route audio and change volume – explaining the need for users to programme the WM5102 chip via terminal commands made through Raspberry Pi’s terminal function, LXTerminal on the desktop.
Terminal commands are, in consumer computing, Neolithic. You write in code on the screen to get the computer to do something. It isn’t easy, convenient or fast, so it was dropped eons ago in favour of icons that invoke pre-written code. So these days we point at a picture or word (Save, Record etc) and the underlying code runs. But this board goes back to terminal work. It isn’t the end of the world but you do need a bit of patience, a keen eye to ensure you entered Lineout and not LineOut, for example, and a list of commands either written down or stored in your head.
Terminal commands also set various parameters such as record sample rate, etc. – and this is where life gets a little taxing, since some of the commands are arcane (weirdly written) and lengthy. However, they are set-up commands used occasionally, whereas the LXmusic player that will see regular use is, thankfully, not command line driven, but works from screen icons just like iTunes etc. – easier, faster and error free.
A difficulty with LXmusic player is that if you wish to play, say, MP3 you must download an MP3 decoder that may or may not be free (MP3 is a proprietary compression algorithm developed by the Fraunhofer Institute, Germany). Our LXmusic player only worked with stereo FLAC files by default, but we were happy to work in FLAC. It does not recognise single-channel mono files either, but these are rare so it isn’t a big issue.
There is more about the audio board’s file compatibility on the forums, but be aware that comments predating 2015 may not be relevant to the Rasperian OS, board software and LXmusic player reviewed here, which are the latest 2015 iterations. See especially ragnar.jensen on http://www.element14.com/community/thread/42202/l/cirrus-logic-audio-card-working-on-the-raspberry-pi-2.
A graphic set up programme called Jack comes bundled in the software to aid set up but ours would not function and wasn’t needed in any case.