LUFA Library

USB Host definitions for the AVR8 microcontrollers. More...

Macros

#define HOST_DEVICE_SETTLE_DELAY_MS   1000
 
#define USB_HOST_DEVICEADDRESS   1
 

Enumerations

enum  USB_Host_EnumerationErrorCodes_t {
  HOST_ENUMERROR_NoError = 0,
  HOST_ENUMERROR_WaitStage = 1,
  HOST_ENUMERROR_NoDeviceDetected = 2,
  HOST_ENUMERROR_ControlError = 3,
  HOST_ENUMERROR_PipeConfigError = 4,
  HOST_ENUMERROR_NoError = 0,
  HOST_ENUMERROR_WaitStage = 1,
  HOST_ENUMERROR_NoDeviceDetected = 2,
  HOST_ENUMERROR_ControlError = 3,
  HOST_ENUMERROR_PipeConfigError = 4
}
 
enum  USB_Host_ErrorCodes_t {
  HOST_ERROR_VBusVoltageDip = 0,
  HOST_ERROR_VBusVoltageDip = 0
}
 

Functions

static void USB_Host_ClearRemoteWakeupSent (void) ATTR_ALWAYS_INLINE
 
static void USB_Host_DisableSOFEvents (void) ATTR_ALWAYS_INLINE
 
static void USB_Host_EnableSOFEvents (void) ATTR_ALWAYS_INLINE
 
static uint16_t USB_Host_GetFrameNumber (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static bool USB_Host_IsBusResetComplete (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static bool USB_Host_IsBusSuspended (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static bool USB_Host_IsDeviceFullSpeed (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static bool USB_Host_IsRemoteWakeupSent (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static bool USB_Host_IsResumeFromWakeupRequestSent (void) ATTR_WARN_UNUSED_RESULT ATTR_ALWAYS_INLINE
 
static void USB_Host_ResetBus (void) ATTR_ALWAYS_INLINE
 
static void USB_Host_ResumeBus (void) ATTR_ALWAYS_INLINE
 
static void USB_Host_ResumeFromWakeupRequest (void) ATTR_ALWAYS_INLINE
 
static void USB_Host_SuspendBus (void) ATTR_ALWAYS_INLINE
 

Detailed Description

Architecture specific USB Host definitions for the Atmel 8-bit AVR microcontrollers.

Macro Definition Documentation

◆ HOST_DEVICE_SETTLE_DELAY_MS

#define HOST_DEVICE_SETTLE_DELAY_MS   1000

Constant for the delay in milliseconds after a device is connected before the library will start the enumeration process. Some devices require a delay of up to 5 seconds after connection before the enumeration process can start or incorrect operation will occur.

The default delay value may be overridden in the user project makefile by defining the HOST_DEVICE_SETTLE_DELAY_MS token to the required delay in milliseconds, and passed to the compiler using the -D switch.

◆ USB_HOST_DEVICEADDRESS

#define USB_HOST_DEVICEADDRESS   1

Indicates the fixed USB device address which any attached device is enumerated to when in host mode. As only one USB device may be attached to the AVR in host mode at any one time and that the address used is not important (other than the fact that it is non-zero), a fixed value is specified by the library.

Enumeration Type Documentation

◆ USB_Host_EnumerationErrorCodes_t

Enum for the error codes for the EVENT_USB_Host_DeviceEnumerationFailed() event.

See also
USB Events for more information on this event.
Enumerator
HOST_ENUMERROR_NoError 

No error occurred. Used internally, this is not a valid ErrorCode parameter value for the EVENT_USB_Host_DeviceEnumerationFailed() event.

HOST_ENUMERROR_WaitStage 

One of the delays between enumeration steps failed to complete successfully, due to a timeout or other error.

HOST_ENUMERROR_NoDeviceDetected 

No device was detected, despite the USB data lines indicating the attachment of a device.

HOST_ENUMERROR_ControlError 

One of the enumeration control requests failed to complete successfully.

HOST_ENUMERROR_PipeConfigError 

The default control pipe (address 0) failed to configure correctly.

HOST_ENUMERROR_NoError 

No error occurred. Used internally, this is not a valid ErrorCode parameter value for the EVENT_USB_Host_DeviceEnumerationFailed() event.

HOST_ENUMERROR_WaitStage 

One of the delays between enumeration steps failed to complete successfully, due to a timeout or other error.

HOST_ENUMERROR_NoDeviceDetected 

No device was detected, despite the USB data lines indicating the attachment of a device.

HOST_ENUMERROR_ControlError 

One of the enumeration control requests failed to complete successfully.

HOST_ENUMERROR_PipeConfigError 

The default control pipe (address 0) failed to configure correctly.

◆ USB_Host_ErrorCodes_t

Enum for the error codes for the EVENT_USB_Host_HostError() event.

See also
USB Events for more information on this event.
Enumerator
HOST_ERROR_VBusVoltageDip 

VBUS voltage dipped to an unacceptable level. This error may be the result of an attached device drawing too much current from the VBUS line, or due to the AVR's power source being unable to supply sufficient current.

HOST_ERROR_VBusVoltageDip 

VBUS voltage dipped to an unacceptable level. This error may be the result of an attached device drawing too much current from the VBUS line, or due to the AVR's power source being unable to supply sufficient current.

Function Documentation

◆ USB_Host_ClearRemoteWakeupSent()

static void USB_Host_ClearRemoteWakeupSent ( void  )
inlinestatic

Clears the flag indicating that a Remote Wakeup request has been issued by an attached device.

◆ USB_Host_DisableSOFEvents()

static void USB_Host_DisableSOFEvents ( void  )
inlinestatic

Disables the host mode Start Of Frame events. When disabled, this stops the firing of the EVENT_USB_Host_StartOfFrame() event when enumerated in host mode.

Note
This function is not available when the NO_SOF_EVENTS compile time token is defined.

◆ USB_Host_EnableSOFEvents()

static void USB_Host_EnableSOFEvents ( void  )
inlinestatic

Enables the host mode Start Of Frame events. When enabled, this causes the EVENT_USB_Host_StartOfFrame() event to fire once per millisecond, synchronized to the USB bus, at the start of each USB frame when a device is enumerated while in host mode.

Note
This function is not available when the NO_SOF_EVENTS compile time token is defined.

◆ USB_Host_GetFrameNumber()

static uint16_t USB_Host_GetFrameNumber ( void  )
inlinestatic

Returns the current USB frame number, when in host mode. Every millisecond the USB bus is active (i.e. not suspended) the frame number is incremented by one.

Returns
Current USB frame number from the USB controller.

◆ USB_Host_IsBusResetComplete()

static bool USB_Host_IsBusResetComplete ( void  )
inlinestatic

Determines if a previously issued bus reset (via the USB_Host_ResetBus() macro) has completed.

Returns
Boolean true if no bus reset is currently being sent, false otherwise.

◆ USB_Host_IsBusSuspended()

static bool USB_Host_IsBusSuspended ( void  )
inlinestatic

Determines if the USB bus has been suspended via the use of the USB_Host_SuspendBus() macro, false otherwise. While suspended, no USB communications can occur until the bus is resumed, except for the Remote Wakeup event from the device if supported.

Returns
Boolean true if the bus is currently suspended, false otherwise.

◆ USB_Host_IsDeviceFullSpeed()

static bool USB_Host_IsDeviceFullSpeed ( void  )
inlinestatic

Determines if the attached device is currently enumerated in Full Speed mode (12Mb/s), or false if the attached device is enumerated in Low Speed mode (1.5Mb/s).

Returns
Boolean true if the attached device is enumerated in Full Speed mode, false otherwise.

◆ USB_Host_IsRemoteWakeupSent()

static bool USB_Host_IsRemoteWakeupSent ( void  )
inlinestatic

Determines if the attached device is currently issuing a Remote Wakeup request, requesting that the host resume the USB bus and wake up the device, false otherwise.

Returns
Boolean true if the attached device has sent a Remote Wakeup request, false otherwise.

◆ USB_Host_IsResumeFromWakeupRequestSent()

static bool USB_Host_IsResumeFromWakeupRequestSent ( void  )
inlinestatic

Determines if a resume from Remote Wakeup request is currently being sent to an attached device.

Returns
Boolean true if no resume request is currently being sent, false otherwise.

◆ USB_Host_ResetBus()

static void USB_Host_ResetBus ( void  )
inlinestatic

Resets the USB bus, including the endpoints in any attached device and pipes on the AVR host. USB bus resets leave the default control pipe configured (if already configured).

If the USB bus has been suspended prior to issuing a bus reset, the attached device will be woken up automatically and the bus resumed after the reset has been correctly issued.

◆ USB_Host_ResumeBus()

static void USB_Host_ResumeBus ( void  )
inlinestatic

Resumes USB communications with an attached and enumerated device, by resuming the transmission of the 1MS Start Of Frame messages to the device. When resumed, USB communications between the host and attached device may occur.

◆ USB_Host_ResumeFromWakeupRequest()

static void USB_Host_ResumeFromWakeupRequest ( void  )
inlinestatic

Accepts a Remote Wakeup request from an attached device. This must be issued in response to a device's Remote Wakeup request within 2ms for the request to be accepted and the bus to be resumed.

◆ USB_Host_SuspendBus()

static void USB_Host_SuspendBus ( void  )
inlinestatic

Suspends the USB bus, preventing any communications from occurring between the host and attached device until the bus has been resumed. This stops the transmission of the 1MS Start Of Frame messages to the device.

Attention
While the USB bus is suspended, all USB interrupt sources are also disabled; this means that some events (such as device disconnections) will not fire until the bus is resumed.