Macros#

Macros.

Macros#

#define
USBX_STRING_DESC (_name, ...)

Macro for creating USB-Compliant UTF-16LE UNICODE string descriptor.

#define
USBX_BUF (x, y)

Macro for creating WORD (4 byte) aligned uint8_t array with size which is a multiple of WORD size.

#define
STATIC_USBX_BUF (x, y)

Macro for creating WORD (4 byte) aligned static uint8_t array with size which is a multiple of WORD size.

Macro Definition Documentation#

USBX_STRING_DESC#

#define USBX_STRING_DESC
Value:
SL_PACK_START(1) \
typedef struct \
{ \
uint8_t len; \
uint8_t type; \
char16_t name[1 + sizeof((char16_t[]){ __VA_ARGS__ }) / 2]; \
} SL_ATTRIBUTE_PACKED _##_name; \
SL_PACK_END() \
SL_ALIGN(4) \
SL_PACK_START(1) \
static const _##_name _name SL_ATTRIBUTE_ALIGN(4) = \
{ \
.len = sizeof(_##_name) - 2, \
.type = 3, \
.name = { __VA_ARGS__ }, \
.name[((sizeof(_##_name) - 2) / 2) - 1] = '\0' \
} \
SL_PACK_END()

Macro for creating USB-Compliant UTF-16LE UNICODE string descriptor.

Example: USBX_STRING_DESC(iManufacturer, 'S','i','l','i','c','o','n',' ' \ 'L','a','b','s'); Note

  • The size of the resulting struct will be two bytes larger than a USB string descriptor. This is to accommodate a terminating null char for the string. The value assigned to the 'len' member does not take this into account and is therefore correct USB-wise.


USBX_BUF#

#define USBX_BUF
Value:
(x, y)

Macro for creating WORD (4 byte) aligned uint8_t array with size which is a multiple of WORD size.

Example: USBX_BUF(rxBuffer, 37); => uint8_t rxBuffer[40];

Note

  • Any data buffer which is written to or read by the USB hardware must be aligned on a WORD (4 byte) boundary. This macro provides an easy way to create USB data buffers which are guaranteed to be correctly aligned.


STATIC_USBX_BUF#

#define STATIC_USBX_BUF
Value:
SL_ALIGN(4) \
static uint8_t x[((y) + 3) & ~3] SL_ATTRIBUTE_ALIGN(4)

Macro for creating WORD (4 byte) aligned static uint8_t array with size which is a multiple of WORD size.

Example: STATIC_USBX_BUF(rxBuffer, 37); => uint8_t rxBuffer[40];

Note

  • Any data buffer which is written to or read by the USB hardware must be aligned on a WORD (4 byte) boundary. This macro provides an easy way to create static USB data buffers which are guaranteed to be correctly aligned.