USB Audio descriptors

nRF5 SDK v12.3.0
Macros

nRF52840 only: Descriptors used in the USB Audio class. More...

Macros

#define APP_USBD_AUDIO_INTERFACE_DSC (interface_number, alt_setting, ep_num, subclass)
Initializer of interface descriptor for AUDIO class. More...
#define APP_USBD_AUDIO_ISO_EP_DSC (ep, ep_size, interval, refresh, synch_addr)
Initializer of isochronous endpoint descriptors for audio class. More...
#define APP_USBD_AUDIO_ISO_EP_IN_DSC (ep_size) APP_USBD_AUDIO_ISO_EP_DSC ( NRF_DRV_USBD_EPIN8 , ep_size, 1, 0, 0)
Simplified version of APP_USBD_AUDIO_ISO_EP_DSC for ISO IN endpoint.
#define APP_USBD_AUDIO_ISO_EP_OUT_DSC (ep_size) APP_USBD_AUDIO_ISO_EP_DSC ( NRF_DRV_USBD_EPOUT8 , ep_size, 1, 0, 0)
Simplified version of APP_USBD_AUDIO_ISO_EP_DSC for ISO OUT endpoint.
#define APP_USBD_AUDIO_AC_IFACE_HEADER_DSC (descriptor_list,...)
Initializer of app_usbd_audio_ac_iface_header_desc_t . More...
#define APP_USBD_AUDIO_INPUT_TERMINAL_DSC (terminal_id, terminal_type, nr_channels, ch_config)
Initializer of app_usbd_audio_input_terminal_desc_t . More...
#define APP_USBD_AUDIO_OUTPUT_TERMINAL_DSC (terminal_id, terminal_type, source_id)
Initializer of app_usbd_audio_output_terminal_desc_t . More...
#define APP_USBD_AUDIO_FEATURE_UNIT_DSC (unit_id, source_id,...)
Initializer of app_usbd_audio_feature_unit_desc_t . More...
#define APP_USBD_AUDIO_AS_IFACE_DSC (terminal_link, delay, format_tag)
Initializer of app_usbd_audio_as_iface_desc_t . More...
#define APP_USBD_AUDIO_AS_FORMAT_I_DSC (nr_channels, subframe_size, resolution, freq_type,...)
Initializer of app_usbd_audio_as_format_type_one_desc_t . More...
#define APP_USBD_AUDIO_AS_FORMAT_II_DSC (max_bitrate, samples_per_frame, freq_type,...)
Initializer of app_usbd_audio_as_format_type_two_desc_t . More...
#define APP_USBD_AUDIO_AS_FORMAT_III_DSC (nr_channels, subframe_size, resolution, freq_type,...)
Initializer of app_usbd_audio_as_format_type_three_desc_t . More...
#define APP_USBD_AUDIO_EP_GENERAL_DSC (attributes, lock_delay_units, lock_delay)
Initializer of app_usbd_audio_as_endpoint_desc_t . More...
#define APP_USBD_AUDIO_CONTROL_DSC (interface_number, descriptor_list, interface_list)
Macro to configure Audio Class control descriptor. More...
#define APP_USBD_AUDIO_STREAMING_DSC (interface_number, alt_setting, ep_num)
Macro to configure Audio Class streaming descriptor. More...
#define APP_USBD_AUDIO_MIDI_STREAMING_DSC (interface_number, alt_setting, ep_num)
Macro to configure Audio Class MIDI streaming descriptor. More...

Detailed Description

nRF52840 only: Descriptors used in the USB Audio class.

Macro Definition Documentation

#define APP_USBD_AUDIO_AC_IFACE_HEADER_DSC ( descriptor_list,
...
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_ac_iface_header_desc_t ) + \
( NUM_VA_ARGS (__VA_ARGS__)), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AC_IFACE_SUBTYPE_HEADER , \
/*.bcdADC = */ APP_USBD_U16_TO_RAW_DSC (0x0100), \
/*.wTotalLength = */ APP_USBD_U16_TO_RAW_DSC ( \
sizeof ((uint8_t[]){ BRACKET_EXTRACT (descriptor_list)}) + \
sizeof ( app_usbd_audio_ac_iface_header_desc_t ) + \
( NUM_VA_ARGS (__VA_ARGS__))), \
/*.bInCollection = */ ( NUM_VA_ARGS (__VA_ARGS__)), \
/*.baInterfaceNr[] = */ __VA_ARGS__, \

Initializer of app_usbd_audio_ac_iface_header_desc_t .

Parameters
descriptor_list Descriptor list following audio interface header descriptor
... List of interfaces following audio control interface
#define APP_USBD_AUDIO_AS_FORMAT_I_DSC ( nr_channels,
subframe_size,
resolution,
freq_type,
...
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_as_format_type_one_desc_t ) + \
( NUM_VA_ARGS (__VA_ARGS__)), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AS_IFACE_SUBTYPE_FORMAT_TYPE , \
/*.bFormatType = */ (1), \
/*.bNrChannels = */ (nr_channels), \
/*.bSubframeSize = */ (subframe_size), \
/*.bBitResolution = */ (resolution), \
/*.bSamFreqType = */ (freq_type), \
/*.tSamFreq = */ __VA_ARGS__, \

Initializer of app_usbd_audio_as_format_type_one_desc_t .

Parameters
nr_channels Number of channels
subframe_size Subframe size
resolution Bit resolution
freq_type Frequency type
... List of frequencies
#define APP_USBD_AUDIO_AS_FORMAT_II_DSC ( max_bitrate,
samples_per_frame,
freq_type,
...
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_as_format_type_two_desc_t ) + \
( NUM_VA_ARGS (__VA_ARGS__)), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AS_IFACE_SUBTYPE_FORMAT_TYPE , \
/*.bFormatType = */ (2), \
/*.wMaxBitRate = */ APP_USBD_U16_TO_RAW_DSC (max_bitrate), \
/*.wSamplesPerFrame = */ APP_USBD_U16_TO_RAW_DSC (samples_per_frame), \
/*.bSamFreqType = */ (freq_type), \
/*.tSamFreq = */ __VA_ARGS__, \

Initializer of app_usbd_audio_as_format_type_two_desc_t .

Parameters
max_bitrate Maximum bitrate
samples_per_frame Samples per frame
freq_type Frequency type
... List of frequencies
#define APP_USBD_AUDIO_AS_FORMAT_III_DSC ( nr_channels,
subframe_size,
resolution,
freq_type,
...
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_as_format_type_three_desc_t ) + \
( NUM_VA_ARGS (__VA_ARGS__)), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AS_IFACE_SUBTYPE_FORMAT_TYPE , \
/*.bFormatType = */ (3), \
/*.bNrChannels = */ (nr_channels), \
/*.bSubframeSize = */ (subframe_size), \
/*.bBitResolution = */ (resolution), \
/*.bSamFreqType = */ (freq_type), \
/*.tSamFreq = */ __VA_ARGS__, \

Initializer of app_usbd_audio_as_format_type_three_desc_t .

Parameters
nr_channels Number of channels
subframe_size Subframe size
resolution Bit resolution
freq_type Frequency type
... List of frequencies
#define APP_USBD_AUDIO_AS_IFACE_DSC ( terminal_link,
delay,
format_tag
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_as_iface_desc_t ), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AS_IFACE_SUBTYPE_GENERAL , \
/*.bTerminalLink = */ (terminal_link), \
/*.bDelay = */ (delay), \
/*.wFormatTag = */ APP_USBD_U16_TO_RAW_DSC (format_tag), \

Initializer of app_usbd_audio_as_iface_desc_t .

Parameters
terminal_link Terminal link
delay Delay
format_tag Format TAG
#define APP_USBD_AUDIO_CONTROL_DSC ( interface_number,
descriptor_list,
interface_list
)
Value:
APP_USBD_AUDIO_INTERFACE_DSC (interface_number, 0, 0, APP_USBD_AUDIO_SUBCLASS_AUDIOCONTROL ) \
APP_USBD_AUDIO_AC_IFACE_HEADER_DSC(descriptor_list, BRACKET_EXTRACT (interface_list)) \
BRACKET_EXTRACT(descriptor_list)

Macro to configure Audio Class control descriptor.

Parameters
interface_number Interface number
descriptor_list List of descriptors after Audio interface header descriptor
interface_list List of interfaces passed to APP_USBD_AUDIO_AC_IFACE_HEADER_DSC
#define APP_USBD_AUDIO_EP_GENERAL_DSC ( attributes,
lock_delay_units,
lock_delay
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_as_endpoint_desc_t ), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_ENDPOINT , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_EP_SUBTYPE_GENERAL , \
/*.bmAttributes = */ (attributes), \
/*.bLockDelayUnits = */ (lock_delay_units), \
/*.wLockDelay = */ APP_USBD_U16_TO_RAW_DSC (lock_delay), \

Initializer of app_usbd_audio_as_endpoint_desc_t .

Parameters
attributes Endpoint attributes
lock_delay_units Lock delay units
lock_delay Lock delay
#define APP_USBD_AUDIO_FEATURE_UNIT_DSC ( unit_id,
source_id,
...
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_feature_unit_desc_t ) + \
1 + ( NUM_VA_ARGS (__VA_ARGS__)), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AC_IFACE_SUBTYPE_FEATURE_UNIT , \
/*.bUnitID = */ (unit_id), \
/*.bSourceID = */ (source_id), \
/*.bControlSize = */ sizeof (uint16_t), \
/*.bmaControls[] = */ __VA_ARGS__, \
/*.iFeature = */ 0, \

Initializer of app_usbd_audio_feature_unit_desc_t .

Parameters
unit_id Unit ID
source_id Source ID
... List of controls
#define APP_USBD_AUDIO_INPUT_TERMINAL_DSC ( terminal_id,
terminal_type,
nr_channels,
ch_config
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_input_terminal_desc_t ), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AC_IFACE_SUBTYPE_INPUT_TERMINAL , \
/*.bTerminalID = */ (terminal_id), \
/*.wTerminalType = */ APP_USBD_U16_TO_RAW_DSC (terminal_type), \
/*.bAssocTerminal = */ 0, \
/*.bNrChannels = */ (nr_channels), \
/*.wChannelConfig = */ APP_USBD_U16_TO_RAW_DSC (ch_config), \
/*.iChannelNames = */ 0, \
/*.iTerminal = */ 0, \

Initializer of app_usbd_audio_input_terminal_desc_t .

Parameters
terminal_id Terminal ID
terminal_type Terminal type app_usbd_audio_terminal_type_t
nr_channels Number of channels
ch_config CHannel config bitmask
#define APP_USBD_AUDIO_INTERFACE_DSC ( interface_number,
alt_setting,
ep_num,
subclass
)
Value:
/*.bLength = */ sizeof ( app_usbd_descriptor_iface_t ), \
/*.bDescriptorType = */ APP_USBD_DESCRIPTOR_INTERFACE , \
/*.bInterfaceNumber = */ (interface_number), \
/*.bAlternateSetting = */ (alt_setting), \
/*.bNumEndpoints = */ (ep_num), \
/*.bInterfaceClass = */ APP_USBD_AUDIO_CLASS , \
/*.bInterfaceSubClass = */ (subclass), \
/*.bInterfaceProtocol = */ APP_USBD_AUDIO_CLASS_PROTOCOL_UNDEFINED , \
/*.iInterface = 0, */ 0x00, \

Initializer of interface descriptor for AUDIO class.

Parameters
interface_number Interface number
alt_setting Interface alternate setting
ep_num Number of endpoints
subclass Audio subclass app_usbd_audio_subclass_t
#define APP_USBD_AUDIO_ISO_EP_DSC ( ep,
ep_size,
interval,
refresh,
synch_addr
)
Value:
/*.bLength = */ sizeof ( app_usbd_descriptor_ep_t ) + 2, \
/*.bDescriptorType = */ APP_USBD_DESCRIPTOR_ENDPOINT , \
/*.bEndpointAddress = */ ep, \
/*.bmAttributes = */ APP_USBD_DESCRIPTOR_EP_ATTR_TYPE_ISOCHRONOUS, \
/*.wMaxPacketSize = */ APP_USBD_U16_TO_RAW_DSC (ep_size), \
/*.bInterval = */ (interval), \
/*.bRefresh = */ (refresh), \
/*.bInterval = */ (synch_addr), \

Initializer of isochronous endpoint descriptors for audio class.

Parameters
ep ISO endpoint id: NRF_DRV_USBD_EPIN8 , NRF_DRV_USBD_EPOUT8
ep_size Endpoint size (bytes)
interval Endpoint interval (milliseconds)
refresh Refresh value (usually 0)
synch_addr Synch address (usually 0)
#define APP_USBD_AUDIO_MIDI_STREAMING_DSC ( interface_number,
alt_setting,
ep_num
)
Value:
APP_USBD_AUDIO_INTERFACE_DSC (interface_number, alt_setting, ep_num, \
APP_USBD_AUDIO_SUBCLASS_MIDISTREAMING )

Macro to configure Audio Class MIDI streaming descriptor.

Parameters
interface_number Interface number
alt_setting Alternate interface setting
ep_num Number of endpoints
#define APP_USBD_AUDIO_OUTPUT_TERMINAL_DSC ( terminal_id,
terminal_type,
source_id
)
Value:
/*.bLength = */ sizeof ( app_usbd_audio_output_terminal_desc_t ), \
/*.bDescriptorType = */ APP_USBD_AUDIO_DESCRIPTOR_INTERFACE , \
/*.bDescriptorSubtype = */ APP_USBD_AUDIO_AC_IFACE_SUBTYPE_OUTPUT_TERNINAL , \
/*.bTerminalID = */ (terminal_id), \
/*.wTerminalType = */ APP_USBD_U16_TO_RAW_DSC (terminal_type), \
/*.bAssocTerminal = */ 0, \
/*.bSourceID = */ (source_id), \
/*.iTerminal = */ 0, \

Initializer of app_usbd_audio_output_terminal_desc_t .

Parameters
terminal_id Terminal ID
terminal_type Terminal type app_usbd_audio_terminal_type_t
source_id Source ID
#define APP_USBD_AUDIO_STREAMING_DSC ( interface_number,
alt_setting,
ep_num
)
Value:
APP_USBD_AUDIO_INTERFACE_DSC (interface_number, alt_setting, ep_num, \
APP_USBD_AUDIO_SUBCLASS_AUDIOSTREAMING )

Macro to configure Audio Class streaming descriptor.

Parameters
interface_number Interface number
alt_setting Alternate interface setting
ep_num Number of endpoints