USB AUDIO 2.0 REFERENCE DESIGN XMOS, USB AUDIO 2.0 REFERENCE DESIGN Datasheet - Page 22

• Manufacturer Part Number: USB AUDIO 2.0 REFERENCE DESIGN
• Description: USB AUDIO 2.0 REFERENCE DESIGN
• Manufacturer: XMOS

Specifications of USB AUDIO 2.0 REFERENCE DESIGN

• Design Resources: USB AUDIO Schematic
• Main Purpose: Audio, Audio Processing
• Embedded: Yes
• Utilized Ic / Part: XS1-L1
• Primary Attributes: Audio data up to 24-bit @ 192kHz
• Secondary Attributes: I²S and S/PDIF
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 880-1017

To implement this control, the decoupler thread uses the feedback value calculated
will insert into the audio FIFO.
The DFU interface handles updates to the boot image of the device. The interface
ways to do this:
USB Audio Software Design Guide
faster or slower than the host. Hence, if the audio clock is slightly fast, the device
may occasionally input/output seven samples rather than six. Alternatively, it may
be slightly slow and input/output five samples rather than six. The following table
shows the allowed number of samples per packet for each example audio frequency.
See USB Device Class Defintion for Audio Data Formats v2.0 section 2.3.1.1 for full
details.
in the buffering thread. This value is used to work out the size of the next packet it
3.5 Device Firmware Upgrade (DFU)
links USB to the XMOS flash user library (see [ToolsUserGuide]). In Application mode
the DFU can accept commands to reset the device into DFU mode. There are two
Once the device is in DFU mode. The DFU interface can accept commands defined
by the USB DFU 1.1 class specification [DFU11]. In addition the interface accepts
the custom command
44.1
48
88.2
96
176.4
192
Frequency (kHz)
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).
interface that resets the device immediately into DFU mode.
The host can send a
The host can send a custom user request
XMOS_DFU_REVERTFACTORY which reverts the active boot image
Table 7: Allowed samples per packet
DETACH request and then reset the device. If the device is
5
5
10
11
20
23
Min Packet
XMOS_DFU_RESETDEVICE to the DFU
6
7
11
13
21
25
Max Packet
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