User Guide

CCS Technical Documentation System Module and User Interface

NEM-2

Communication interface specified below provides wake- up capability as well. Either

DCT4 Phone or Audio Player will wake- up on activity at the receive lines.

Communication

DCT4 Phone- Audio Player communication interface is serial, UART based asynchronous

interface. Two lines (RxD and TxD) are used. At DCT4 Phone side LPRF UART of UPP is

used. At Audio Player side McBSP0 of DA250 is used.

ADSP internal timer 0 is used for McBSP0 transmit clock. Therefore timer output pin

"TOUT0" is connected to McBSP0 pin "CLKX".

Audio

Two different audio sources are distributed form DCT4 Phone to Audio Player part:

•GSM_HF

• FMRadioOutL, FMRadioOutR

Audio Player

Audio concept is basing on application DSP TMS320DA250. As audio hardware codec

(AD/DA converter) a TLV320AIC23B is used. As FM-radio TEA5767 is used.

The stereo audio hardware codec includes AD- and DA-converter, input amplifier, output

amplifier and headphone amplifier. The headphone amplifier is designed for loads with

resistance greater 16 ohms. The used headset resistance is 32 ohm. The minimal specified

load resistance is 0 ohm in the hardware codec specification. That means that the output

circuit is shortcut protected

Audio Features

Following audio features are supported:

• Telephony in private mode

• Telephony via headset

• Playback from MP3/AAC files via headset

• FM radio via headset

• Recording from analog source via line in or from FM radio in AAC format

• Loading from MP3/AAC files via USB

• Monitoring the recording source via headset

• MP3/AAC ringing tones