PCM2901

PCM2903

SLES034B − MARCH 2002 − REVISED JUNE 2004

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Interface #0

Interface #0 is defined as the control interface. Alternative setting #0 is the only possible setting for interface

#0. Alternative setting #0 describes the standard audio control interface. A terminal constructs the audio control

interface. The PCM2901/2903 has the following five terminals.

Input terminal #1 is defined as USB stream (terminal type 0x0101). Input terminal #1 can accept 2-channel audio

streams constructed by left and right channels. Output terminal #2 is defined as a speaker (terminal type

0x0301). Input terminal #4 is defined as microphone (terminal type 0x0201). Output terminal #5 is defined as

a USB stream (terminal type 0x0101). Output terminal #5 can generate 2-channel audio streams constructed

by left and right channels. Feature unit #3 supports the following sound control features.

The built-in digital volume controller can be manipulated by an audio class specific request from 0 dB to –64 dB

until the volume level has reached the requested value. Each channel can be set for different values. The master

volume control is not supported. A request to the master volume is stalled and ignored. The built-in digital mute

controller can be manipulated by audio class specific request. A master mute control request is acceptable. A

request to an individual channel is stalled and ignored.

Interface #1

Interface #1 is defined as the audio streaming data-out interface. Interface #1 has the following seven

alternative settings. Alternative setting #0 is the zero bandwidth setting.

ALTERNATIVE

SETTING

DATA FORMAT

TRANSFER

MODE

SAMPLING RATE

(kHz)

00

Zero bandwidth

01

16 bit

Stereo

2s complement (PCM)

Adaptive

32, 44.1, 48

02

16 bit

Mono

2s complement (PCM)

Adaptive

32, 44.1, 48

03

8 bit

Stereo

2s complement (PCM)

Adaptive

32, 44.1, 48

04

8 bit

Mono

2s complement (PCM)

Adaptive

32, 44.1, 48

05

8 bit

Stereo

Offset binary (PCM8)

Adaptive

32, 44.1, 48

06

8 bit

Mono

Offset binary (PCM8)

Adaptive

32, 44.1, 48