Basic SSC-I2S AT73C213 Project 1.3

Purpose

This example uses the Synchronous Serial Controller (SSC) of an AT91 microcontroller to output an audio steam through the on-board AT73C213 audio DAC.

Description

This program plays a WAV file pre-loaded into the external SDRAM. The audio stream is sent through the SSC interface connected to the on-board AT73C213, enabling the sound to be audible using a pair of headphones.

Since the AT73C213 DAC requires that it be feeded a master clock multiple of the sample rate, it is difficult to handle any WAV file. As such, this example application is limited to playing files with the following format:

• Format: WAV
• Sample rate: 48 kHz

Usage

1. Build the program and download it inside the evaluation board using SAM-BA. Please refer to the SAM-BA User Guide for more information about this step.
2. Using SAM-BA, download the provided WAV file inside the external SDRAM at address 0x20005000.
3. Plug earphones to the audio jack of the evaluation board.
4. On the computer, open the DBGU port with a terminal application (e.g. HyperTerminal on Microsoft Windows).
• Settings: 115200 bauds, 8 bits, 1 stop bit, no parity, no flow control.
5. Start the application.
6. The application menu should appear as shown below (unless the provided WAV file is invalid):

   -- Basic SSC I2S AT73C213 Project 1.4 --
Menu :
------
W: Play the WAV file pre-loaded in SDRAM
I: Display the information of the WAV file


   The user can then choose any of the available options to perform the described action.

Atmel Corporation ©2008