我正在尝试使用STMicroelectronics的USB-FS库在STM32F103上实现USB麦克风。
在Windows XP,7和8上检测到我的麦克风。 当我尝试使用Audacity录制语音时,信号在Windows XP和Windows 8上是正确的,但对于Windows 7,它会被放大。
有没有人知道发生了什么?
这是描述符:
const uint8_t Mic_ConfigDescriptor[] =
{
/* Configuration 1 */
0x09, /* bLength */
USB_CONFIGURATION_DESCRIPTOR_TYPE, /* bDescriptorType */
0x64, /* wTotalLength = 100 bytes */
0x00,
0x02, /* bNumInterfaces */
0x01, /* bConfigurationValue */
0x00, /* iConfiguration */
0x80, /* bmAttributes BUS Powred*/
0x32, /* bMaxPower = 100 mA*/
/* 09 byte*/
/* Interface 0, Alternate Setting 0, USB Microphone Standard AC Interface Descriptor */
9, /* bLength */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
0x00, /* bInterfaceNumber */
0x00, /* bAlternateSetting */
0x00, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDIOCONTROL, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* USB Microphone Class-specific AC Interface Descriptor */
9, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_HEADER, /* bDescriptorSubtype */
0x01, /* 1.00 */ /* bcdADC */
0x00,
0x1E, /* wTotalLength = 30*/
0x00,
0x01, /* bInCollection */
0x01, /* baInterfaceNr */
/* 09 byte*/
/* USB Microphone Input Terminal Descriptor */
AUDIO_INPUT_TERMINAL_DESC_SIZE, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_INPUT_TERMINAL, /* bDescriptorSubtype */
0x01, /* bTerminalID */
0x01, /* wTerminalType: terminal is Micro = 0x0201 */
0x02,
0x00, /* bAssocTerminal */
0x02, /* bNrChannels */
0x00, /* wChannelConfig 0x0000 Mono */
0x00,
0x00, /* iChannelNames */
0x00, /* iTerminal */
/* 12 byte*/
/* USB Microphone Output Terminal Descriptor*/
//AUDIO_OUTPUT_TERMINAL_DESC_SIZE, /* bLength */
0x09,
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_OUTPUT_TERMINAL, /* bDescriptorSubtype */
0x02, /* bTerminalID */
0x01, /* wTerminalType AUDIO_USB_STREAMING. 0x0101*/
0x01,
0x00, /* bAssocTerminal */
0x01, /* bSourceID */
0x00, /* iTerminal */
/* 09 byte*/
/* Interface 1, Alternate Setting 0, Audio Streaming - Zero Bandwith */
9, /* bLength */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
0x01, /* bInterfaceNumber */
0x00, /* bAlternateSetting */
0x00, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDIOSTREAMING, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* Interface 1, Alternate Setting 1, Audio Streaming - Operational */
9, /* bLength */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
0x01, /* bInterfaceNumber */
0x01, /* bAlternateSetting */
0x01, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDIOSTREAMING, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* USB Microphone Class-specific AS General Interface Descriptor */
AUDIO_STREAMING_INTERFACE_DESC_SIZE, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_STREAMING_GENERAL, /* bDescriptorSubtype */
0x02, /* bTerminalLink */
0x00, /* bDelay */
0x01, /* wFormatTag AUDIO_FORMAT_PCM8 0x0002*/
0x00,
/* 07 byte*/
/* USB Microphone Type I Format Type Descriptor */
0x0B, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_STREAMING_FORMAT_TYPE, /* bDescriptorSubtype */
AUDIO_FORMAT_TYPE_I, /* bFormatType */
0x01, /* bNrChannels */
0x02, /* bSubFrameSize */
16, /* bBitResolution */
0x01, /* bSamFreqType */
0x40, /* tSamFreq 8KHz = 0x1F40 */
0x1F,
0x00,
/* 11 byte*/
/* USB Microphone Standard Endpoint Descriptor */
AUDIO_STANDARD_ENDPOINT_DESC_SIZE, /* bLength */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType */
//AUDIO_IN_EP, /* bEndpointAddress 1 IN endpoint*/
0x81, /* bEndpointAddress 1 IN endpoint*/
0x01,//USB_ENDPOINT_TYPE_ISOCHRONOUS, /* 01: Asynchronous, 10: Adaptive, 11: synchronous. bmAttributes */
16, /* wMaxPacketSize 22 bytes*/
0x00,
0x01, /* bInterval */
0x00, /* bRefresh */
0x00, /* bSynchAddress */
/* 09 byte*/
/* USB Microphone Class-specific Isoc. Audio Data Endpoint Descriptor */
AUDIO_STREAMING_ENDPOINT_DESC_SIZE, /* bLength */
AUDIO_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_ENDPOINT_GENERAL, /* bDescriptor */
0x00, /* bmAttributes */
0x00, /* bLockDelayUnits */
0x00, /* wLockDelay */
0x00,
/* 07 byte*/
}
答案 0 :(得分:2)
此问题已解决:必须在描述符+特定于音频类的请求的响应中实现功能单元。
答案 1 :(得分:0)
如果未为输入路径定义功能部件,则Windows 7和更高版本将添加数字增益控件。 (Windows XP和macOS只会显示无法调整的灰色滑块。)
但是,Windows 7 has a bug that sets this digital control to +30 dB gain by default for Microphones:
因此,或者在第一次插入麦克风后将增益降低到0 dB,将终端类型设置为除麦克风之外的其他值,或者定义功能部件。