Power; Required User Function Definitions; External Audio Hardware Configuration Functions - XMOS xCORE-200 Multi-channel Audio board Design Manual

USB Audio Design Guide
Macro VOLUME_RES_MIXER
Description The resolution of the volume control in db as a 8.8 fixed point number.
Default: 0x100 (1db)

7.1.10 Power

Macro SELF_POWERED
Description Report as self to the host when enabled, else reports as bus-powered.
This affects descriptors and XUD usage.
Default: 0 (Disabled)
Macro BMAX_POWER
Description Power drawn from the host (in mA x 2).
Default: 0 when SELF_POWERED enabled else 250 (500mA)
7.2 Required User Function Definitions
The following functions need to be defined by an application using the XMOS USB Audio framework.
7.2.1 External Audio Hardware Configuration Functions
Function AudioHwInit
Description This function is called when the audio core starts after the device boots up and
should initialize the external audio harware e.g. clocking, DAC, ADC etc
Type
void AudioHwInit(chanend ?c_codec)
Parameters
c_codec
Function AudioHwConfig
This function is called when the audio core starts or changes sample rate. It
Description
should configure the extenal audio hardware to run at the specified sample rate
given the supplied master clock frequency.
XM0088546.1
An optional chanend that was original passed into
can be used to communicate with other cores.
100/110
audio()
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