Technical Reference Guide
5.8.4 AUDIO CODEC
The audio codec provides pulse code modulation (PCM) coding and decoding of audio information as well as the selection and/or mixing of analog channels. As shown in Figure
Analog audio may then be routed through 3D stereo enhancement processor or bypassed to the output selector (SEL). The integrated analog mixer provides the computer
The D315 and D325 models use the Analog Devices AD1885 and the AD1981B respectively. These devices differ in that the AD1885 includes a 3D analog processor while the AD1981B includes an equalizer as well as SPDIF support.
Mic In
Line In (L)
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CD In (L) CD In (R)
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DAC
DAC
PB Data (L)
EQ
PB Data (R)
EQ
AC97
Link
I/F
SD IN
SD Out
Audio Controller
Figure 5-12. Audio Codec Functional Block Diagram and Difference Matrix
5.8.5 AUDIO PROGRAMMING
Compaq D315 and hp d325 Personal
Featuring the AMD Athlon XP Processor
Second Edition - April 2003