USBD_CfgAdd

Description

Adds a configuration to the device.

Files

usbd_core.h/usbd_core.c

Prototype

CPU_INT08U  USBD_CfgAdd (       CPU_INT08U     dev_nbr,
                                CPU_INT08U     attrib,
                                CPU_INT16U     max_pwr,
                                USBD_DEV_SPD   spd,
                         const  CPU_CHAR      *p_name,
                                USBD_ERR      *p_err);

Arguments

dev_nbr

Device number.

attrib

Configuration attributes.

USBD_DEV_ATTRIB_REMOTE_WAKEUP

USBD_DEV_ATTRIB_SELF_POWERED

max_pwr

Bus power required for this device (see Note #1).

spd

Configuration speed.

USBD_DEV_SPD_FULL

USBD_DEV_SPD_HIGH

p_name

Pointer to string describing the configuration (See Note #2).

p_err

Pointer to variable that will receive the return error code from this function.

USBD_ERR_NONE

USBD_ERR_DEV_INVALID_NBR

USBD_ERR_DEV_INVALID_STATE

USBD_ERR_CFG_ALLOC

USBD_ERR_CFG_INVALID_MAX_PWR

Returned Value

Configuration number, If no error(s).

USBD_CFG_NBR_NONE, otherwise.

Callers

Application.

Notes / Warnings

USB spec 2.0, section 7.2.1.3/4 defines power constrains for bus-powered devices:
1. “A low-power function is one that draws up to one unit load from the USB cable when operational”
2. “A function is defined as being high-power if, when fully powered, it draws over one but no more than five unit loads from the USB cable.”
A unit load is defined as 100mA, thus max_pwr argument should be between 0 mA and 500mA.
String support is optional, in this case 'p_name' can be a NULL string pointer.
Configuration can only be added when the device is in either the USBD_DEV_STATE_NONE or USB_DEV_STATE_INIT states.