Integrator/CP User Guide - ARM Information Center

Peripherals and Interfaces4.5 Audio interfaceThis section describes the audio interface in:• Hardware interface• PrimeCell AACI functional overview on page 4-21• AACI registers on page 4-25.4.5.1 Hardware interfaceThe baseboard provides a National Semiconductor LM4549 audio CODEC. The audioCODEC is compatible with AC’97 Rev 2.1 and features sample rate conversion and 3Dsound. The CODEC is driven with a PrimeCell AACI (PL041) instantiated into the coremodule FPGA.Figure 4-9 shows the architecture of audio interface. (Line out is the top connector.)HDRBAACI_SDATA_OUTAACI_BIT_CLKAACI_SYNCAACI_SDATA_INAACI_RESETCODEC_MIC1LM4549AudioCODEC(U18)CODEC_LINE_OUT_LCODEC_LINE_OUT_RCODEC_LINE_IN_LCODEC_LINE_IN_R5V_ANALOGLM4880(U20)AMP_LAMP_RJ10(top)J10(bottom)Stacked 3.5 mmjack socketsJ12CODEC_MIC212MIC_BIASLK12K2100R3GNDFigure 4-9 Audio interfaceThe CODEC is provided with a microphone input that can be configured by a link tosupport either passive or dynamic (electret) microphones:• link 1 and 2 to support an active microphone with power on MIC1 (tip)• link 2 and 3 to support an active microphone with power on MIC2 (ring 2)• omit the link to support a passive microphone.The default configuration supports a passive microphone. Only monophonic sound issupported, but microphone channel MIC1 or MIC2 can be selected in software.4-20 Copyright © 2002 ARM Limited. All rights reserved. ARM DUI 0159B