WM8904 Example

Purpose

This example uses the Synchronous Serial Controller (SSC) of SAM devices to output an audio stream through the on-board WM8904 CODEC.

Requirements

This example can be used with SAM Xplained board kits with the on-board WM8904 CODEC.

Description

This program plays sound from PC via Line-In. The audio stream is sent through the SSC interface connected to the on-board WM8904, enabling the sound to be audible using a pair of headphones.

The code can be roughly broken down as follows:

• Enable the clock.
• Initialize and configure the Codec.
• Configure and enable the SSC.
• Configure and enable the XDMA.

Usage

1. Build the program and download it into the Xplained board.
2. On the computer, open and configure a terminal application (e.g. HyperTerminal on Microsoft Windows) with these settings:
   • 115200 baud rate
   • 8 bits of data
   • No parity
   • 1 stop bit
   • No flow control
3. Start the application.
4. In the terminal window, the following text should appear:

   -- WM8904 example xxx --
   -- SAMxx-xx
   -- Compiled: xxx xx xxxx xx:xx:xx --