EAGLE
PRELIMINARY
Ver 1.3
3.12
Sound Mixer
3.12.1 Features
1. Sound data stored inside the external memory can be simultaneously played back for up to eight channels.
2. The Sound data format is selected from 4-bit ADPCM, 8-bit PCM and 16-bit PCM.
3. The Sound Mixer’s AMBA Master interface controls the sound data residing in external memory. Continuous
access and loop playback between selective address is possible.
4. The sound signal produced by stereo is in 16-bit MSB (Left)-justified format with 44.1KHz in sampling frequency.
The codec clock is connected to an external oscillator of 16.9355 MHz to obtain accurate sampling frequency, or it
is generated through the division of system clock in Pre-Scaler.
5. Each of the eight channel is capable of controlling the frequency of sound data playback ranging from 0.172 KHz
to 44.1 KHz in 256 steps, volume is adjusted in 256 steps and balance in 16 steps.
3.12.2 Block Diagram
Figure 3-17 Sound Mixer Block Diagram
Beijing Peak Microtech Co.Ltd.
CONFIDENTIAL
120
ETC [ ETC ]
