CM6571 Datasheet, PDF (24/63 Pages) C-Media Electronics – USB 2.0 full speed-compliant

CM6571
USB Audio Sound Chip
class-specific feature unit descriptor (microphone recording) , ID=06
Offset
Field
Size Value (Hex)
Description
0
bLength
1
0A
Descriptor length
1
bDescriptorType
1
24
CS_INTERFACE descriptor type
2
bDescriptorSubtype 1
06
FEATURE_UNIT descriptor subtype
3
bUnitID
1
06
Unit ID
4
bSourceID
1
02
Source ID from Input Unit: 02
5
bControlSize
1
01
Size in byte of bmaControls array: 1 bytes
6
bmaControls(1)
1
01
master mute 01
7
bmaControls(2)
1
02
Left Front volume control
02 : stereo
8
bmaControls(3)
1
02
Right Front volume control
02 : stereo
9
iFeature
1
00
Index of string descriptor describing this Feature Unit
class-specific feature unit descriptor (microphone recording) , ID=07
Offset
Field
Size Value (Hex)
Description
0
bLength
1
0A
Descriptor length
1
bDescriptorType
1
24
CS_INTERFACE descriptor type
2
bDescriptorSubtype 1
06
FEATURE_UNIT descriptor subtype
3
bUnitID
1
07
Unit ID
4
bSourceID
1
02
Source ID from Input Unit: 02
5
bControlSize
1
01
Size in byte of bmaControls array: 1 bytes
6
bmaControls(1)
1
01
master mute 01
7
bmaControls(2)
1
02
Left Front volume control
02 : stereo
8
bmaControls(3)
1
02
Right Front volume control
02 : stereo
9
iFeature
1
00
Index of string descriptor describing this Feature Unit
class-specific selector unit descriptor (USB stream), ID=08
Offset
Field
Size Value (Hex)
Description
0
bLength
1
07
Descriptor length
1
bDescriptorType
1
24
CS_INTERFACE descriptor type
2
bDescriptorSubtype 1
05
SELECTOR_UNIT descriptor subtype
3
bUnitID
1
08
Unit ID
4
bNrInPins
1
01
Number of input pin
5
bmaControls(1)
1
06
Microphone Feature
6
iSelector
1
00
Index of string descriptor describing this Selector Unit
class-specific mixer unit descriptor (speaker), ID=09
Offset
Field
Size Value (Hex)
Description
0
bLength
1
0D
Descriptor length
1
bDescriptorType
1
24
CS_INTERFACE descriptor type
2
bDescriptorSubtype 1
04
MIXER_UNIT descriptor subtype
3
bUnitID
1
09
Unit ID
4
bNrInPins
1
02
Number of input pin
5
baSourceID(1)
1
01
USB Stream
6
baSourceID(2)
1
07
Microphone Feature
7
bNrChannels
1
02
Number of output channel
8
wChannelConfig
2
0003
D0: Left Front (L)
D1: Right Front (R)
10
iChannelNames
1
00
Index of string descriptor describing the name of the
first logical channel
11
bmControls
1
00
All mixing controls are not programmable (this field
occupies (2+2+2)*2/8 bytes)
Revised: Nov. 2012
Page 24 / 63
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