Features & Options; Device Firmware Upgrade (Dfu); Usb Audio Class Version Support - XMOS xCORE-200 Multi-channel Audio board Design Manual

4 Features & Options
IN TH I S C H A P T ER

Device Firmware Upgrade (DFU)

USB Audio Class Version Support

Audio Controls via Human Interface Device (HID)
Apple MFi compatibility
Audio Stream Formats
DSD over PCM (DoP)
This section looks at some of the available features of the USB Audio design.
4.1 Device Firmware Upgrade (DFU)
The DFU interface handles updates to the boot image of the device. The DFU code
is called from the Endpoint 0 core.
The interface links USB to the XMOS flash user library (see XM-000953-PC). In
Application mode the DFU can accept commands to reset the device into DFU mode.
There are two ways to do this:
The host can send a DETACH request and then reset the device. If the device is
reset by the host within a specified timeout, it will start in DFU mode (this is
initially set to one second and is configurable from the host).
The host can send a custom user request XMOS_DFU_RESETDEVICE to the DFU
interface that resets the device immediately into DFU mode.
Once the device is in DFU mode. The DFU interface can accept commands defined
by the DFU 1.1 class specification
command XMOS_DFU_REVERTFACTORY which reverts the active boot image to the
factory image. Note that the XMOS specific command request identifiers are
defined in dfu_types.h within module_dfu .
4.2 USB Audio Class Version Support
The XMOS USB Audio framework supports both USB Audio Class 1.0 and Audio
Class 2.0.
USB Audio Class 2.0 offers many improvements over USB Audio Class 1.0, most
notable is the complete support for high-speed operation. This means that Audio
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http://www.usb.org/developers/devclass_docs/DFU_1.1.pdf*USB
XM0088546.1
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. In addition the interface accepts the custom