nRF5 SDK v13.0.0
Data Structures | Macros | Typedefs | Enumerations | Functions
USB Device raw IP driver

nRF52840 only: USB Device raw IP driver. More...

Data Structures

struct  nrf_drv_usbd_evt_t
 Event structure. More...
 
union  nrf_drv_usbd_data_ptr_t
 Universal data pointer. More...
 
struct  nrf_drv_usbd_ep_transfer_t
 Structure to be filled with information about the next transfer. More...
 
struct  nrf_drv_usbd_transfer_t
 Total transfer configuration. More...
 
union  nrf_drv_usbd_handler_t
 Universal transfer handler. More...
 
struct  nrf_drv_usbd_handler_desc_t
 USBD transfer descriptor. More...
 
struct  nrf_drv_usbd_setup_t
 Setup packet structure. More...
 

Macros

#define NRF_DRV_USBD_EPSIZE   64
 Number of bytes in the endpoint. More...
 
#define NRF_DRV_USBD_ISOSIZE   1024
 Number of bytes for isochronous endpoints. More...
 
#define NRF_DRV_USBD_FEEDER_BUFFER_SIZE   NRF_DRV_USBD_EPSIZE
 The size of internal feeder buffer. More...
 
#define NRF_DRV_USBD_TRANSFER_IN_FLAGS(name, tx_buff, tx_size, tx_flags)
 Auxiliary macro for declaring IN transfer description with flags. More...
 
#define NRF_DRV_USBD_TRANSFER_IN(name, tx_buff, tx_size)   NRF_DRV_USBD_TRANSFER_IN_FLAGS(name, tx_buff, tx_size, 0)
 Helper macro for declaring IN transfer description. More...
 
#define NRF_DRV_USBD_TRANSFER_IN_ZLP(name, tx_buff, tx_size)
 Helper macro for declaring IN transfer description. More...
 
#define NRF_DRV_USBD_TRANSFER_OUT(name, rx_buff, rx_size)
 Helper macro for declaring OUT transfer item (nrf_drv_usbd_transfer_t) More...
 

Typedefs

typedef void(* nrf_drv_usbd_event_handler_t )(nrf_drv_usbd_evt_t const *const p_event)
 USBD event callback function type. More...
 
typedef bool(* nrf_drv_usbd_feeder_t )(nrf_drv_usbd_ep_transfer_t *p_next, void *p_context, size_t ep_size)
 USBD transfer feeder. More...
 
typedef bool(* nrf_drv_usbd_consumer_t )(nrf_drv_usbd_ep_transfer_t *p_next, void *p_context, size_t ep_size, size_t data_size)
 USBD transfer consumer. More...
 

Enumerations

enum  nrf_drv_usbd_ep_t {
  NRF_DRV_USBD_EPOUT0 = NRF_USBD_EPOUT(0),
  NRF_DRV_USBD_EPOUT1 = NRF_USBD_EPOUT(1),
  NRF_DRV_USBD_EPOUT2 = NRF_USBD_EPOUT(2),
  NRF_DRV_USBD_EPOUT3 = NRF_USBD_EPOUT(3),
  NRF_DRV_USBD_EPOUT4 = NRF_USBD_EPOUT(4),
  NRF_DRV_USBD_EPOUT5 = NRF_USBD_EPOUT(5),
  NRF_DRV_USBD_EPOUT6 = NRF_USBD_EPOUT(6),
  NRF_DRV_USBD_EPOUT7 = NRF_USBD_EPOUT(7),
  NRF_DRV_USBD_EPOUT8 = NRF_USBD_EPOUT(8),
  NRF_DRV_USBD_EPIN0 = NRF_USBD_EPIN(0),
  NRF_DRV_USBD_EPIN1 = NRF_USBD_EPIN(1),
  NRF_DRV_USBD_EPIN2 = NRF_USBD_EPIN(2),
  NRF_DRV_USBD_EPIN3 = NRF_USBD_EPIN(3),
  NRF_DRV_USBD_EPIN4 = NRF_USBD_EPIN(4),
  NRF_DRV_USBD_EPIN5 = NRF_USBD_EPIN(5),
  NRF_DRV_USBD_EPIN6 = NRF_USBD_EPIN(6),
  NRF_DRV_USBD_EPIN7 = NRF_USBD_EPIN(7),
  NRF_DRV_USBD_EPIN8 = NRF_USBD_EPIN(8)
}
 Endpoint identifier. More...
 
enum  nrf_drv_usbd_event_type_t {
  NRF_DRV_USBD_EVT_SOF,
  NRF_DRV_USBD_EVT_RESET,
  NRF_DRV_USBD_EVT_SUSPEND,
  NRF_DRV_USBD_EVT_RESUME,
  NRF_DRV_USBD_EVT_SETUP,
  NRF_DRV_USBD_EVT_EPTRANSFER,
  NRF_DRV_USBD_EVT_CNT
}
 Events generated by the library. More...
 
enum  nrf_drv_usbd_ep_status_t {
  NRF_USBD_EP_OK,
  NRF_USBD_EP_WAITING,
  NRF_USBD_EP_OVERLOAD,
  NRF_USBD_EP_ABORTED
}
 Possible endpoint error codes. More...
 
enum  nrf_drv_usbd_transfer_flags_t { NRF_DRV_USBD_TRANSFER_ZLP_FLAG = 1U << 0 }
 Flags for the current transfer. More...
 

Functions

ret_code_t nrf_drv_usbd_init (nrf_drv_usbd_event_handler_t const event_handler)
 Library initialization. More...
 
ret_code_t nrf_drv_usbd_uninit (void)
 Library deinitialization.
 
void nrf_drv_usbd_enable (void)
 Enable the USBD port. More...
 
void nrf_drv_usbd_disable (void)
 Disable the USBD port. More...
 
void nrf_drv_usbd_start (bool enable_sof)
 Start USB functionality. More...
 
void nrf_drv_usbd_stop (void)
 Stop USB functionality. More...
 
bool nrf_drv_usbd_is_initialized (void)
 Check if driver is initialized. More...
 
bool nrf_drv_usbd_is_enabled (void)
 Check if driver is enabled. More...
 
bool nrf_drv_usbd_is_started (void)
 Check if driver is started. More...
 
void nrf_drv_usbd_ep_max_packet_size_set (nrf_drv_usbd_ep_t ep, uint16_t size)
 Configure packet size that should be supported by the endpoint. More...
 
uint16_t nrf_drv_usbd_ep_max_packet_size_get (nrf_drv_usbd_ep_t ep)
 Get configured endpoint packet size. More...
 
bool nrf_drv_usbd_ep_enable_check (nrf_drv_usbd_ep_t ep)
 Check if the selected endpoint is enabled. More...
 
void nrf_drv_usbd_ep_enable (nrf_drv_usbd_ep_t ep)
 Enable selected endpoint. More...
 
void nrf_drv_usbd_ep_disable (nrf_drv_usbd_ep_t ep)
 Disable selected endpoint. More...
 
ret_code_t nrf_drv_usbd_ep_transfer (nrf_drv_usbd_ep_t ep, nrf_drv_usbd_transfer_t const *const p_transfer)
 Start sending data over endpoint. More...
 
ret_code_t nrf_drv_usbd_ep_handled_transfer (nrf_drv_usbd_ep_t ep, nrf_drv_usbd_handler_desc_t const *const p_handler)
 Start sending data over the endpoint using the transfer handler function. More...
 
void * nrf_drv_usbd_feeder_buffer_get (void)
 Get the temporary buffer to be used by the feeder. More...
 
ret_code_t nrf_drv_usbd_ep_status_get (nrf_drv_usbd_ep_t ep, size_t *p_size)
 Get the information about last finished or current transfer. More...
 
size_t nrf_drv_usbd_epout_size_get (nrf_drv_usbd_ep_t ep)
 Get number of received bytes. More...
 
bool nrf_drv_usbd_ep_is_busy (nrf_drv_usbd_ep_t ep)
 Check if endpoint buffer is ready or is under USB IP control. More...
 
void nrf_drv_usbd_ep_stall (nrf_drv_usbd_ep_t ep)
 Stall endpoint. More...
 
void nrf_drv_usbd_ep_stall_clear (nrf_drv_usbd_ep_t ep)
 Clear stall flag on endpoint. More...
 
bool nrf_drv_usbd_ep_stall_check (nrf_drv_usbd_ep_t ep)
 Check if endpoint is stalled. More...
 
void nrf_drv_usbd_setup_get (nrf_drv_usbd_setup_t *const p_setup)
 Get parsed setup data. More...
 
void nrf_drv_usbd_setup_data_clear (void)
 Clear only for data transmission on setup endpoint. More...
 
void nrf_drv_usbd_setup_clear (void)
 Clear setup endpoint. More...
 
void nrf_drv_usbd_setup_stall (void)
 Stall setup endpoint. More...
 
void usbd_drv_ep_abort (nrf_drv_usbd_ep_t ep)
 
nrf_drv_usbd_ep_t nrf_drv_usbd_last_setup_dir_get (void)
 Get the information about expected transfer SETUP data direction. More...
 
void nrf_drv_usbd_transfer_out_drop (nrf_drv_usbd_ep_t ep)
 Drop transfer on OUT endpoint. More...
 

Possible schemes of DMA scheduling

Definition of available configuration constants used by DMA scheduler

#define NRF_DRV_USBD_DMASCHEDULER_PRIORITIZED   0
 Highly prioritized access. More...
 
#define NRF_DRV_USBD_DMASCHEDULER_ROUNDROBIN   1
 Round robin scheme. More...
 

Macros for creating endpoint identifiers

Auxiliary macros to be used to create Endpoint identifier that is compatible with USB specification.

#define NRF_DRV_USBD_EPIN(n)   ((nrf_drv_usbd_ep_t)NRF_USBD_EPIN(n))
 Create identifier for IN endpoint. More...
 
#define NRF_DRV_USBD_EPOUT(n)   ((nrf_drv_usbd_ep_t)NRF_USBD_EPOUT(n))
 Create identifier for OUT endpoint. More...
 

Detailed Description

nRF52840 only: USB Device raw IP driver.

Macro Definition Documentation

#define NRF_DRV_USBD_DMASCHEDULER_PRIORITIZED   0

Highly prioritized access.

Endpoint with lower number has always higher priority and its data would be transfered first. OUT endpoints ale processed before IN endpoints

#define NRF_DRV_USBD_DMASCHEDULER_ROUNDROBIN   1

Round robin scheme.

All endpoints are processed in round-robin scheme. It means that when one endpoint is processed next in order would be the nearest with lower number. When no endpoints with lower number requires processing - then all endpoints from 0 are tested.

#define NRF_DRV_USBD_EPIN (   n)    ((nrf_drv_usbd_ep_t)NRF_USBD_EPIN(n))

Create identifier for IN endpoint.

Simple macro to create IN endpoint identifier for given endpoint number.

Parameters
[in]nEndpoint number.
Returns
Endpoint identifier that connects endpoint number and endpoint direction.
#define NRF_DRV_USBD_EPOUT (   n)    ((nrf_drv_usbd_ep_t)NRF_USBD_EPOUT(n))

Create identifier for OUT endpoint.

Simple macro to create OUT endpoint identifier for given endpoint number.

Parameters
[in]nEndpoint number.
Returns
Endpoint identifier that connects endpoint number and endpoint direction.
#define NRF_DRV_USBD_EPSIZE   64

Number of bytes in the endpoint.

Constant that informs about endpoint size

#define NRF_DRV_USBD_FEEDER_BUFFER_SIZE   NRF_DRV_USBD_EPSIZE

The size of internal feeder buffer.

See Also
nrf_drv_usbd_feeder_buffer_get
#define NRF_DRV_USBD_ISOSIZE   1024

Number of bytes for isochronous endpoints.

Number of bytes for isochronous endpoints in total. This number would be shared between IN and OUT endpoint. It may be also assigned totaly to one endpoint.

See Also
nrf_usbd_isosplit_set
nrf_usbd_isosplit_get
#define NRF_DRV_USBD_TRANSFER_IN (   name,
  tx_buff,
  tx_size 
)    NRF_DRV_USBD_TRANSFER_IN_FLAGS(name, tx_buff, tx_size, 0)

Helper macro for declaring IN transfer description.

Normal transfer mode, no ZLP would be automatically generated.

See Also
nrf_drv_usbd_transfer_t
NRF_DRV_USBD_TRANSFER_IN_ZLP
Parameters
nameInstance name
tx_buffBuffer to transfer
tx_sizeTransfer size
Returns
Configured variable with total transfer description
#define NRF_DRV_USBD_TRANSFER_IN_FLAGS (   name,
  tx_buff,
  tx_size,
  tx_flags 
)
Value:
const nrf_drv_usbd_transfer_t name = { \
.p_data = { .tx = (tx_buff) }, \
.size = (tx_size), \
.flags = (tx_flags) \
}

Auxiliary macro for declaring IN transfer description with flags.

The base macro for creating transfers with any configuration option.

Parameters
nameInstance name.
tx_buffBuffer to transfer.
tx_sizeTransfer size.
tx_flagsFlags for the transfer (see nrf_drv_usbd_transfer_flags_t).
Returns
Configured variable with total transfer description.
#define NRF_DRV_USBD_TRANSFER_IN_ZLP (   name,
  tx_buff,
  tx_size 
)
Value:

Helper macro for declaring IN transfer description.

ZLP mode - Zero Length Packet would be generated on the end of the transfer (always!).

See Also
nrf_drv_usbd_transfer_t
NRF_DRV_USBD_TRANSFER_IN
Parameters
nameInstance name
tx_buffBuffer to transfer
tx_sizeTransfer size
Returns
Configured variable with total transfer description
#define NRF_DRV_USBD_TRANSFER_OUT (   name,
  rx_buff,
  rx_size 
)
Value:
const nrf_drv_usbd_transfer_t name = { \
.p_data = { .rx = (rx_buff) }, \
.size = (rx_size), \
.flags = 0 \
}

Helper macro for declaring OUT transfer item (nrf_drv_usbd_transfer_t)

Parameters
nameInstance name
rx_buffBuffer to transfer
rx_sizeTransfer size

Typedef Documentation

typedef bool(* nrf_drv_usbd_consumer_t)(nrf_drv_usbd_ep_transfer_t *p_next, void *p_context, size_t ep_size, size_t data_size)

USBD transfer consumer.

Pointer for a transfer consumer. Transfer consumer is a feedback function used to prepare a single RX (Host->Device) endpoint transfer.

The transfer must provide a buffer big enough to fit the whole data from the endpoint. Otherwise, the NRF_USBD_EP_OVERLOAD event is generated.

Parameters
[out]p_nextStructure with the data for the next transfer to be filled. Required only if the function returns true.
[in,out]p_contextContext variable configured with the transfer.
[in]ep_sizeThe endpoint size.
[in]data_sizeNumber of received bytes in the endpoint buffer.
Return values
falseCurrent transfer is the last one - you do not need to call the function again.
trueThere is more data to be prepared and when current transfer finishes, the feeder function is expected to be called again.
typedef void(* nrf_drv_usbd_event_handler_t)(nrf_drv_usbd_evt_t const *const p_event)

USBD event callback function type.

Parameters
[in]p_eventEvent information structure.
typedef bool(* nrf_drv_usbd_feeder_t)(nrf_drv_usbd_ep_transfer_t *p_next, void *p_context, size_t ep_size)

USBD transfer feeder.

Pointer for a transfer feeder. Transfer feeder is a feedback function used to prepare a single TX (Device->Host) endpoint transfer.

The transfers provided by the feeder must be simple:

  • The size of the transfer provided by this function is limited to a single endpoint buffer. Bigger transfers are not handled automatically in this case.
  • Flash transfers are not automatically supported- you must copy them to the RAM buffer before.
Note
This function may use nrf_drv_usbd_feeder_buffer_get to gain a temporary buffer that can be used to prepare transfer.
Parameters
[out]p_nextStructure with the data for the next transfer to be filled. Required only if the function returns true.
[in,out]p_contextContext variable configured with the transfer.
[in]ep_sizeThe endpoint size.
Return values
falseThe current transfer is the last one - you do not need to call the function again.
trueThere is more data to be prepared and when the current transfer finishes, the feeder function is expected to be called again.

Enumeration Type Documentation

Possible endpoint error codes.

Error codes that may be returned with NRF_DRV_USBD_EVT_EPTRANSFER

Enumerator
NRF_USBD_EP_OK 

No error

NRF_USBD_EP_WAITING 

Data received, no buffer prepared already - waiting for configured transfer

NRF_USBD_EP_OVERLOAD 

Received number of bytes cannot fit given buffer This error would also be returned when next_transfer function has been defined but currently received data cannot fit completely in current buffer. No data split from single endpoint transmission is supported.

When this error is reported - data is left inside endpoint buffer. Clear endpoint or prepare new buffer and read it.

NRF_USBD_EP_ABORTED 

EP0 transfer can be aborted when new setup comes. Any other transfer can be aborted by USB reset or library stopping.

Endpoint identifier.

Endpoint identifier used in the driver. This endpoint number is consistent with USB 2.0 specification.

Enumerator
NRF_DRV_USBD_EPOUT0 

Endpoint OUT 0

NRF_DRV_USBD_EPOUT1 

Endpoint OUT 1

NRF_DRV_USBD_EPOUT2 

Endpoint OUT 2

NRF_DRV_USBD_EPOUT3 

Endpoint OUT 3

NRF_DRV_USBD_EPOUT4 

Endpoint OUT 4

NRF_DRV_USBD_EPOUT5 

Endpoint OUT 5

NRF_DRV_USBD_EPOUT6 

Endpoint OUT 6

NRF_DRV_USBD_EPOUT7 

Endpoint OUT 7

NRF_DRV_USBD_EPOUT8 

Endpoint OUT 8

NRF_DRV_USBD_EPIN0 

Endpoint IN 0

NRF_DRV_USBD_EPIN1 

Endpoint IN 1

NRF_DRV_USBD_EPIN2 

Endpoint IN 2

NRF_DRV_USBD_EPIN3 

Endpoint IN 3

NRF_DRV_USBD_EPIN4 

Endpoint IN 4

NRF_DRV_USBD_EPIN5 

Endpoint IN 5

NRF_DRV_USBD_EPIN6 

Endpoint IN 6

NRF_DRV_USBD_EPIN7 

Endpoint IN 7

NRF_DRV_USBD_EPIN8 

Endpoint IN 8

Events generated by the library.

Enumeration of possible events that may be generated by the library.

Enumerator
NRF_DRV_USBD_EVT_SOF 

Start Of Frame event on USB bus detected

NRF_DRV_USBD_EVT_RESET 

Reset condition on USB bus detected

NRF_DRV_USBD_EVT_SUSPEND 

This device should go to suspend mode now

NRF_DRV_USBD_EVT_RESUME 

This device should resume from suspend now

NRF_DRV_USBD_EVT_SETUP 

Setup frame received and decoded

NRF_DRV_USBD_EVT_EPTRANSFER 

For Rx (OUT: Host->Device):

  1. The packet has been received but there is no buffer prepared for transfer already.
  2. Whole transfer has been finished

For Tx (IN: Device->Host): The last packet from requested transfer has been transfered over USB bus and acknowledged

NRF_DRV_USBD_EVT_CNT 

Number of defined events

Flags for the current transfer.

Flags configured for the transfer that can be merged using the bitwise 'or' operator (|).

Enumerator
NRF_DRV_USBD_TRANSFER_ZLP_FLAG 

Add a zero-length packet.

Function Documentation

void nrf_drv_usbd_disable ( void  )

Disable the USBD port.

After calling this function USBD peripheral would be disabled. No events would be detected or processed by the library. Clock for the peripheral would be disconnected.

void nrf_drv_usbd_enable ( void  )

Enable the USBD port.

After calling this function USBD peripheral would be enabled. It means that High Frequency clock would be requested and USB LDO would be enabled.

In normal situation this function should be called in reaction to USBDETECTED event from POWER peripheral.

Interrupts and USB pins pull-up would stay disabled until nrf_drv_usbd_start function is called.

void nrf_drv_usbd_ep_disable ( nrf_drv_usbd_ep_t  ep)

Disable selected endpoint.

This function disables endpoint itself and its interrupts.

Parameters
epEndpoint number to disable
void nrf_drv_usbd_ep_enable ( nrf_drv_usbd_ep_t  ep)

Enable selected endpoint.

This function enables endpoint itself and its interrupts.

Parameters
epEndpoint number to enable
Note
Max packet size is set to endpoint default maximum value.
See Also
nrf_drv_usbd_ep_max_packet_size_set
bool nrf_drv_usbd_ep_enable_check ( nrf_drv_usbd_ep_t  ep)

Check if the selected endpoint is enabled.

Parameters
epEndpoint number to check.
Return values
trueEndpoint is enabled.
falseEndpoint is disabled.
ret_code_t nrf_drv_usbd_ep_handled_transfer ( nrf_drv_usbd_ep_t  ep,
nrf_drv_usbd_handler_desc_t const *const  p_handler 
)

Start sending data over the endpoint using the transfer handler function.

This function initializes an endpoint transmission. Just before data is transmitted, the transfer handler is called and it prepares a data chunk.

Parameters
[in]epEndpoint number. For an IN endpoint, sending is initiated. For an OUT endpoint, receiving is initiated.
p_handlerTransfer handler - feeder for IN direction and consumer for OUT direction.
Return values
NRF_ERROR_BUSYSelected endpoint is pending.
NRF_ERROR_INVALID_ADDRUnexpected transfer on EPIN0 or EPOUT0.
NRF_ERROR_FORBIDDENEndpoint stalled.
NRF_SUCCESSTransfer queued or started.
bool nrf_drv_usbd_ep_is_busy ( nrf_drv_usbd_ep_t  ep)

Check if endpoint buffer is ready or is under USB IP control.

Function to test if endpoint is busy. Endpoint that is busy cannot be accessed by MCU. It means that:

  • OUT (TX) endpoint: Last uploaded data is still in endpoint and is waiting to be received by the host.
  • IN (RX) endpoint: Endpoint is ready to receive data from the host and the endpoint does not have any data. When endpoint is not busy:
  • OUT (TX) endpoint: New data can be uploaded.
  • IN (RX) endpoint: New data can be downloaded using nrf_drv_usbd_ep_transfer function.
uint16_t nrf_drv_usbd_ep_max_packet_size_get ( nrf_drv_usbd_ep_t  ep)

Get configured endpoint packet size.

Function to get configured endpoint size on the buffer.

Parameters
[in]epEndpoint number
Returns
Maximum pocket size configured on selected endpoint
void nrf_drv_usbd_ep_max_packet_size_set ( nrf_drv_usbd_ep_t  ep,
uint16_t  size 
)

Configure packet size that should be supported by the endpoint.

The real endpoint buffer size is always the same. This value sets max packet size that would be transmitted over the endpoint. This is required by the library

Parameters
[in]epEndpoint number
[in]sizeRequired maximum packet size
Note
Endpoint size is always set to NRF_DRV_USBD_EPSIZE or NRF_DRV_USBD_ISOSIZE / 2 when nrf_drv_usbd_ep_enable function is called.
void nrf_drv_usbd_ep_stall ( nrf_drv_usbd_ep_t  ep)

Stall endpoint.

Stall endpoit to send error information during next transfer request from the host.

Note
To stall endpoint it is safer to use nrf_drv_usbd_setup_stall
Stalled endpoint would not be cleared when DMA transfer finishes.
Parameters
epEndpoint number to stall
bool nrf_drv_usbd_ep_stall_check ( nrf_drv_usbd_ep_t  ep)

Check if endpoint is stalled.

This function gets stall state of selected endpoint

Parameters
epEndpoint number to check
void nrf_drv_usbd_ep_stall_clear ( nrf_drv_usbd_ep_t  ep)

Clear stall flag on endpoint.

This function clears endpoint that is stalled.

Note
If it is OUT endpoint (receiving) it would be also prepared for reception. It means that busy flag would be set.
In endpoint (transmitting) would not be cleared - it gives possibility to write new data before transmitting.
ret_code_t nrf_drv_usbd_ep_status_get ( nrf_drv_usbd_ep_t  ep,
size_t *  p_size 
)

Get the information about last finished or current transfer.

Function returns the status of the last buffer set for transfer on selected endpoint. The status considers last buffer set by nrf_drv_usbd_ep_transfer function or by transfer callback function.

Parameters
[in]epEndpoint number.
[out]p_sizeInformation about the current/last transfer size.
Return values
NRF_SUCCESSTransfer already finished
NRF_ERROR_BUSYOngoing transfer
NRF_ERROR_DATA_SIZEToo much of data received that cannot fit into buffer and cannot be splited into chunks. This may happen if buffer size is not a multiplication of endpoint buffer size.
ret_code_t nrf_drv_usbd_ep_transfer ( nrf_drv_usbd_ep_t  ep,
nrf_drv_usbd_transfer_t const *const  p_transfer 
)

Start sending data over endpoint.

Function initializes endpoint transmission. This is asynchronous function - it finishes immediately after configuration for transmission is prepared.

Note
Data buffer pointed by p_data have to be kept active till NRF_DRV_USBD_EVT_EPTRANSFER event is generated.
Parameters
[in]epEndpoint number. For IN endpoint sending would be initiated. For OUT endpoint receiving would be initiated.
[in]p_transfer
Return values
NRF_ERROR_BUSYSelected endpoint is pending.
NRF_ERROR_INVALID_ADDRUnexpected transfer on EPIN0 or EPOUT0.
NRF_ERROR_FORBIDDENEndpoint stalled.
NRF_SUCCESSTransfer queued or started.
size_t nrf_drv_usbd_epout_size_get ( nrf_drv_usbd_ep_t  ep)

Get number of received bytes.

Get the number of received bytes. The function behavior is undefined when called on IN endpoint.

Parameters
epEndpoint number.
Returns
Number of received bytes
void* nrf_drv_usbd_feeder_buffer_get ( void  )

Get the temporary buffer to be used by the feeder.

This buffer is used for TX transfers and it can be reused automatically when the transfer is finished. Use it for transfer preparation.

May be used inside the feeder configured in nrf_drv_usbd_ep_handled_transfer.

Returns
Pointer to the buffer that can be used temporarily.
See Also
NRF_DRV_USBD_FEEDER_BUFFER_SIZE
ret_code_t nrf_drv_usbd_init ( nrf_drv_usbd_event_handler_t const  event_handler)

Library initialization.

Parameters
[in]event_handlerEvent handler provided by the user.
bool nrf_drv_usbd_is_enabled ( void  )

Check if driver is enabled.

Return values
falseDriver is disabled
trueDriver is enabled
bool nrf_drv_usbd_is_initialized ( void  )

Check if driver is initialized.

Return values
falseDriver is not initialized
trueDriver is initialized
bool nrf_drv_usbd_is_started ( void  )

Check if driver is started.

Return values
falseDriver is not started
trueDriver is started (fully functional)
Note
The USBD peripheral interrupt state is checked
nrf_drv_usbd_ep_t nrf_drv_usbd_last_setup_dir_get ( void  )

Get the information about expected transfer SETUP data direction.

Function returns the information about last expected transfer direction.

Return values
NRF_DRV_USBD_EPOUT0Expecting OUT (Host->Device) direction or no data
NRF_DRV_USBD_EPIN0Expecting IN (Device->Host) direction
void nrf_drv_usbd_setup_clear ( void  )

Clear setup endpoint.

This function acknowledges setup when SETUP command was received and processed. It has to be called if no data respond for the SETUP command is sent.

When there is any data transmission after SETUP command the data transmission itself would clear the endpoint.

void nrf_drv_usbd_setup_data_clear ( void  )

Clear only for data transmission on setup endpoint.

This function may be called if any more data in control write transfer is expected. Clears only OUT endpoint to be able to take another OUT data token. It does not allow STATUS stage.

See Also
nrf_drv_usbd_setup_clear
void nrf_drv_usbd_setup_get ( nrf_drv_usbd_setup_t *const  p_setup)

Get parsed setup data.

Function fills the parsed setup data structure.

Parameters
[out]p_setupPointer to data structure that would be filled by parsed data.
void nrf_drv_usbd_setup_stall ( void  )

Stall setup endpoint.

Mark and error on setup endpoint.

void nrf_drv_usbd_start ( bool  enable_sof)

Start USB functionality.

After calling this function USBD peripheral should be fully functional and all new incoming events / interrupts would be processed by the library.

Also only after calling this function host sees new connected device.

Call this function when USBD power LDO regulator is ready - on USBPWRRDY event from POWER peripheral.

Parameters
enable_sofThe flag that is used to enable SOF processing. If it is false, SOF interrupt is left disabled and will not be generated. This improves power saving if SOF is not required.
Note
If the isochronous endpoints are going to be used, it is required to enable the SOF. In other case any isochronous endpoint would stay busy after first transmission.
void nrf_drv_usbd_stop ( void  )

Stop USB functionality.

This function disables USBD pull-up and interrupts.

Note
This function can also be used to logically disconnect USB from the HOST that would force it to enumerate device after calling nrf_drv_usbd_start.
void nrf_drv_usbd_transfer_out_drop ( nrf_drv_usbd_ep_t  ep)

Drop transfer on OUT endpoint.

Parameters
[in]epOUT endpoint ID
void usbd_drv_ep_abort ( nrf_drv_usbd_ep_t  ep)
Note
This function locks interrupts that may be costly. It is good idea to test if the endpoint is still busy before calling this function:
(m_ep_dma_waiting & (1U << ep2bit(ep)))
This function would check it again, but it makes it inside critical section.

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