CM118B Datasheet, PDF (7/25 Pages) C-Media Electronics – Highly Integrated & Configurable USB Audio Single Chip

CM118B
Highly Integrated & Configurable USB Audio Single Chip
3. USB Topology
The CM118B supports USB Headset / USB Speaker / USB Microphone topology that can be selected by pins.
Detail setting please refer to chapter 6.4 – Jumper Pins and Mode Setting
3.1 Headset Topology with Mixer
0X01
0X0F
0X09
0X06
IT
MIXER
FEA
OT
0X0D
FEA
0X02
0X0A
IT
FEA
0X08
0X07
SEL
OT
Device Descriptor
Offset
Field
Size
0
bLength
1
1
bDescriptorType
1
2
bcdUSB
2
4
bDeviceClass
1
5
bDeviceSubClass
1
6
bDeviceProtocol
1
7
bMaxPacketSize0
1
8
idVendor
2
10
idProduct
2
12
bcdDevice
2
14
iManufacturer
1
15
iProduct
1
16
iSerialNumber
1
17 bNumConfigurations
1
Configuration Descriptor
Offset
Field
Size
0
bLength
1
1
bDescriptorType
1
2
wTotalLength
2
4
bNumInterfaces
1
Datasheet Revision: 1.00
Page 7 / 25
Value (Hex)
Description
12 Total 18 Bytes
01 Device descriptor
0110 USB 1.1 compliant
00 Device class specified by interface
00 Device subclass specified by interface
00 Device protocol specified by interface
8
Endpoint zero Size = 8 bytes
0d8c Vendor ID
0016 Product ID
0100
Device compliant to the Audio Device Class specification
version 1.00
01
Index of string descriptor that characterizes the
manufacturer
02 Index of string descriptor that characterizes the product
00
Index of string descriptor that characterizes the device’s
serial number
01 Configurations number = 1
Value (Hex)
Description
09 Total 9 Bytes
02 Configuration descriptor
XXXX Total length of data returned for this configuration:
Programmable by MSEL and MODE pin
04
Number of interfaces supported by this configuration:
0: control interface
1: ISO-OUT interface
www.cmedia.com.tw
Copyright© C-Media Electronics Inc.