Build time options

This section lists build time configuration defines that impact the behaviour of lib_xud.

XUD_OSC_MHZ

Frequency of oscillator used to clock xcore (in MHz)

XUD_SUSPEND_PHY

Option to put the PHY in low power mode during USB suspend.

When set to 1, the PHY will enter low power mode during USB suspend. When set to 0 (default), this feature is disabled.

Only supported on XS3A/xcore.ai based devices.

XUD_USB_ISO_MAX_TXNS_PER_MICROFRAME

Maximum number of transactions per microframe for an ISO endpoint.

Defines how many transactions an isochronous (ISO) endpoint can perform in a single USB microframe. This value controls whether high-bandwidth ISO support is enabled.

• Default: 1

• Maximum supported value: 2

Applications can include a custom xud_conf.h file to override this value.

Setting this to a value greater than 1 enables ISO High Bandwidth support in lib_xud.

XUD_USB_ISO_EP_MAX_TXN_SIZE

Max data payload per ISO transaction (in bytes).

Must not exceed 1024, per USB 2.0 spec limit for high-speed isochronous transfers.

Default: 1024

Applications can include a custom xud_conf.h file to override this value.