Descriptors.c File Reference

USB Device Descriptors, for library use when in USB device mode. More...

#include "Descriptors.h"

Functions
uint16_t	CALLBACK_USB_GetDescriptor (const uint16_t wValue, const uint8_t wIndex, const void **const DescriptorAddress)
	This function is called by the library when in device mode, and must be overridden (see library "USB Descriptors" documentation) by the application code so that the address and size of a requested descriptor can be given to the USB library.
Variables
USB_Descriptor_Device_t PROGMEM	DeviceDescriptor
	Device descriptor structure.
USB_Descriptor_Configuration_t PROGMEM	ConfigurationDescriptor
	Configuration descriptor structure.
USB_Descriptor_String_t PROGMEM	LanguageString
	Language descriptor structure.
USB_Descriptor_String_t PROGMEM	ManufacturerString
	Manufacturer descriptor string.
USB_Descriptor_String_t PROGMEM	ProductString
	Product descriptor string.

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Detailed Description

USB Device Descriptors, for library use when in USB device mode.

Descriptors are special computer-readable structures which the host requests upon device enumeration, to determine the device's capabilities and functions.

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Function Documentation

uint16_t CALLBACK_USB_GetDescriptor	(	const uint16_t	wValue,
		const uint8_t	wIndex,
		const void **const	DescriptorAddress
	)

This function is called by the library when in device mode, and must be overridden (see library "USB Descriptors" documentation) by the application code so that the address and size of a requested descriptor can be given to the USB library.

When the device receives a Get Descriptor request on the control endpoint, this function is called so that the descriptor details can be passed back and the appropriate descriptor sent back to the USB host.

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Variable Documentation

USB_Descriptor_Configuration_t PROGMEM ConfigurationDescriptor

Configuration descriptor structure.

This descriptor, located in FLASH memory, describes the usage of the device in one of its supported configurations, including information about any device interfaces and endpoints. The descriptor is read out by the USB host during the enumeration process when selecting a configuration so that the host may correctly communicate with the USB device.

Referenced by CALLBACK_USB_GetDescriptor().

USB_Descriptor_Device_t PROGMEM DeviceDescriptor

Initial value:

{
  .Header                 = {.Size = sizeof(USB_Descriptor_Device_t), .Type = DTYPE_Device},

  .USBSpecification       = VERSION_BCD(01.10),
  .Class                  = CDC_CSCP_CDCClass,
  .SubClass               = CDC_CSCP_NoSpecificSubclass,
  .Protocol               = CDC_CSCP_NoSpecificProtocol,

  .Endpoint0Size          = FIXED_CONTROL_ENDPOINT_SIZE,

  .VendorID               = 0x03EB,
  .ProductID              = 0x2044,
  .ReleaseNumber          = VERSION_BCD(00.01),

  .ManufacturerStrIndex   = 0x01,
  .ProductStrIndex        = 0x02,
  .SerialNumStrIndex      = USE_INTERNAL_SERIAL,

  .NumberOfConfigurations = FIXED_NUM_CONFIGURATIONS
}

Device descriptor structure.

This descriptor, located in FLASH memory, describes the overall device characteristics, including the supported USB version, control endpoint size and the number of device configurations. The descriptor is read out by the USB host when the enumeration process begins.

Referenced by CALLBACK_USB_GetDescriptor().

USB_Descriptor_String_t PROGMEM LanguageString

Initial value:

{
  .Header                 = {.Size = USB_STRING_LEN(1), .Type = DTYPE_String},

  .UnicodeString          = {LANGUAGE_ID_ENG}
}

Language descriptor structure.

This descriptor, located in FLASH memory, is returned when the host requests the string descriptor with index 0 (the first index). It is actually an array of 16-bit integers, which indicate via the language ID table available at USB.org what languages the device supports for its string descriptors.

Referenced by CALLBACK_USB_GetDescriptor().

USB_Descriptor_String_t PROGMEM ManufacturerString

Initial value:

{
  .Header                 = {.Size = USB_STRING_LEN(6), .Type = DTYPE_String},

  .UnicodeString          = L"Reprap"
}

Manufacturer descriptor string.

This is a Unicode string containing the manufacturer's details in human readable form, and is read out upon request by the host when the appropriate string ID is requested, listed in the Device Descriptor.

Referenced by CALLBACK_USB_GetDescriptor().

USB_Descriptor_String_t PROGMEM ProductString

Initial value:

{
  .Header                 = {.Size = USB_STRING_LEN(13), .Type = DTYPE_String},

  .UnicodeString          = L"Teacup Reprap"
}

Product descriptor string.

This is a Unicode string containing the product's details in human readable form, and is read out upon request by the host when the appropriate string ID is requested, listed in the Device Descriptor.

Referenced by CALLBACK_USB_GetDescriptor().