AK5371AVQ AKM [Asahi Kasei Microsystems], AK5371AVQ Datasheet - Page 26

• Manufacturer Part Number: AK5371AVQ
• Description: 2ch A/D Converter with USB I/F
• Manufacturer: AKM [Asahi Kasei Microsystems]

MS0546-E-00
5 Device specific Requests
AKM USB Microphone supports ONLY SET_CUR as bRequest field in Set Request Values.
5.1 Audio Control Request
AKM USB microphone support ONLY Feature Unit Control Request, not support other requests. Addition to this,
it only supports SET_CUR value as bRequest field in Set Feature Unit Control Request Values. All Audio Control
Requests are applied to channel 0,1,2, which means master , left and right channel.
5.1.1
AKM USB Microphone supports only one form of parameter block. Mute control is applied to master channel
(channel 0)
a) Mute Control
Offset
0
1
2
4
6
The parameter block of mute control is the following.
Offset
0
a) Volume Control
Left (channel 1) volume and right (channel 2) volume are controlled independently.
Offset
0
1
2
4
6
The parameter block of mute control is the following.
Offset
0
If the wVolume exceeds the range, the AK5371A forces the value into the range. Please see the conversion table in
the Get Feature Unit Control Request.
ASAHI KASEI
MS0103-E-00
Set Feature Unit Control Request
Field
bmRequestType
bRequest
wValue
wIndex
wLength
Field
bMute
Field
bmRequestType
bRequest
wValue
wIndex
wLength
Field
wVolume
Size
Size
Size
Size
1
1
2
2
2
1
1
1
2
2
2
2
Value
0x21
0x01
0x0100
0x0300
0x0001
Value
0x01
0x00
Value
0x21
0x01
0x0201
0x0202
0x0300
0x0002
Value
0xZZZZ
Description
SET_CUR
MUTE_CONTROL | CHANNEL_0
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
The Length of Mute Control Parameter Block
Description
TRUE
FALSE
Description
SET_CUR
VOLUME_CONTROL | CHANNEL_1
VOLUME_CONTROL | CHANNEL_2
Upper Byte : bUnit ID field in Feature Unit
Descriptor.(0x03)
Lower Byte : Audio Control Interface(0x00)
Volume Control
Description
The value is mapped to the volume register value.
(refer to Table 1 conversion table )
ZZZZ is assigned by the host
26
[AK5371A]
2007/02