Pc Usb Demonstration Kit And Record-Replay Applications; Pc Usb Demonstration Kit Application - ST STM32 User Manual

UM0722
function. All requests that are concerned with the manipulation of certain audio
controls within the audio function's units or terminals must be directed to the
AudioControl interface of the audio function. Likewise, all descriptors related to the
internals of the audio function are part of the class-specific AudioControl interface
descriptor.
● AudioStreaming Interface Subclass (AS): AudioStreaming interfaces are used to
interchange digital audio data streams between the host and the audio function. They
are optional. An audio function can have zero or more AudioStreaming interfaces
associated with it, each possibly carrying data of a different nature and format. Each
AudioStreaming interface can have at most one isochronous data endpoint.
●
MIDIStreaming Interface Subclass (MIDIS): MIDIStreaming interfaces are used to
transport MIDI data streams into and out of the audio function. To be able to manipulate
the physical properties of an audio function, its functionality must be divided into
addressable entities. Two types of such generic entities are identified and are called
units and terminals. The Universal Serial Bus Class Definition for audio devices
specification defines seven types of standard units and terminals that are considered
adequate to represent most audio functions. These are:
– Input terminal
– Output terminal
– Mixer unit
– Selector unit
– Feature unit
– Processing unit
– Extension unit
For more information about the audio class characteristics and requirements please refer to
the Universal Serial Bus Device Class Definition for audio devices specification provided by
the usb.org website.
11.3

PC USB demonstration kit and record-replay applications

In order to demonstrate all capabilities of the TS4657 audio card is the delivered user
application structured into two operation modes: PC USB demonstration kit and record-
replay.
11.3.1

PC USB demonstration kit application

This part of the demonstration firmware gives examples of how to use the STM32F10xxx
USB-FS-device peripheral to communicate with the PC host in the isochronous transfer
mode. The code provides a demonstration of the correct method for configuring an
isochronous endpoint, receiving or transmitting data from/to the host and also shows how to
use the data in a real-time application.
www.BDTIC.com/ST
Doc ID 15867 Rev 1
Demonstration kit software
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