USB Configuration

Due to the nature of the USB enumeration process, USB setup must be done using a Data Partition so that the configuration is complete prior to enumeration. The following table summarises the USB interface parameters which can be configured.

Table 48 USB configuration parameters

Command

Ty pe

A rguments

Definition

SET_USB_VENDOR_ID

GET_USB_VENDOR_ID

ui nt 32

1

Set USB Vendor ID. See notes A, B.

S ET_USB_PRODUCT_ID

G ET_USB_PRODUCT_ID

ui nt 32

1

Set USB Product ID. See notes A, B.

S ET_USB_BCD_DEVICE

G ET_USB_BCD_DEVICE

ui nt 32

1

Set USB Device Release Number (bcdDevice). See notes A, B.

SET_USB _VENDOR_STRING

GET_USB _VENDOR_STRING

u in t8

25

Set USB Vendor string. See notes A, B.

SET_U SB_PRODUCT_STRING

GET_U SB_PRODUCT_STRING

u in t8

25

Set USB Product string. See notes A, B.

SET_USB _SERIAL_NUMBER

GET_USB _SERIAL_NUMBER

ui nt 32

1

Write only register, setting the behaviour of iSerialNumber field in USB descriptor (See notes A, B.):

1 - Load from Flash Serial Number

0 - Default to 0 .

SET_U SB_TO_DEVICE_RATE

GET_U SB_TO_DEVICE_RATE

ui nt 32

1

Set sampling frequency of USB reference from USB host. Default is 48000 samples/sec. See notes A, B.

SET_D EVICE_TO_USB_RATE

GET_D EVICE_TO_USB_RATE

ui nt 32

1

Set sampling frequency of audio output to USB host. Default device_to_usb_rate is 48000 samples/sec. See notes A, B.

SET_USB_TO _DEVICE_BIT_RES

GET_USB_TO _DEVICE_BIT_RES

ui nt 32

1

Set bit depth of USB reference from USB host. Default usb_to_device_bit_res is 16 bits. See notes A, B.

SET_DEVI CE_TO_USB_BIT_RES

GET_DEVI CE_TO_USB_BIT_RES

ui nt 32

1

Set bit depth of audio output to USB host. Default device_to_usb_bit_res is 16 bits. See notes A, B.

SET _USB_START_STATUS

GET _USB_START_STATUS

u in t8

1

Start USB. Set as 1 as the last USB item in Data Partition. See notes A.

A: Command supported for Data Partition use only

B: Command must occur before SET_USB_START_STATUS 1