User API reference of the Communication Device Class (ACM). More...

Functions
void	USBD_CDCn_ACM_Initialize (void)
	Called during USBD_Initialize to initialize the USB CDC class instance (ACM)

void	USBD_CDCn_ACM_Uninitialize (void)
	Called during USBD_Uninitialize to de-initialize the USB CDC class instance (ACM)

void	USBD_CDCn_ACM_Reset (void)
	Called upon USB Bus Reset Event.

bool	USBD_CDCn_ACM_SetLineCoding (CDC_LINE_CODING *line_coding)
	Called upon USB Host request to change communication settings.

bool	USBD_CDCn_ACM_GetLineCoding (CDC_LINE_CODING *line_coding)
	Called upon USB Host request to retrieve communication settings.

bool	USBD_CDCn_ACM_SetControlLineState (uint16_t state)
	Called upon USB Host request to set control line states.

void	USBD_CDCn_ACM_DataReceived (uint32_t len)
	Called when new data was received.

void	USBD_CDCn_ACM_DataSent (void)
	Called when all data was sent.

int32_t	USBD_CDC_ACM_WriteData (uint8_t instance, const uint8_t *buf, int32_t len)
	Write data from Communication Device to USB Host.

int	USBD_CDC_ACM_PutChar (uint8_t instance, int ch)
	Write a single character from Communication Device to USB Host.

int32_t	USBD_CDC_ACM_ReadData (uint8_t instance, uint8_t *buf, int32_t len)
	Read multiple data bytes received by Communication Device from USB Host.

int	USBD_CDC_ACM_GetChar (uint8_t instance)
	Read one character received by Communication Device from USB Host.

int32_t	USBD_CDC_ACM_DataAvailable (uint8_t instance)
	Retrieve number of data bytes received by Communication Device from USB Host that are available to read.

usbStatus	USBD_CDC_ACM_Notify (uint8_t instance, uint16_t state)
	Send notification of Communication Device status and line states to USB Host.

Description

User API reference of the Communication Device Class (ACM).

Function Documentation

int32_t USBD_CDC_ACM_DataAvailable ( uint8_t instance )

Retrieve number of data bytes received by Communication Device from USB Host that are available to read.

Parameters

[in] instance instance of CDC class.

Returns: number of bytes available to read.

The function USBD_CDC_ACM_DataAvailable returns the number of bytes available in the intermediate buffer that was received from the USB Host by the CDC device instance that is specified by the argument instance.

int USBD_CDC_ACM_GetChar ( uint8_t instance )

Read one character received by Communication Device from USB Host.

Parameters

[in] instance instance of CDC class.

Returns

value of read character or no character received.

value >= 0: value of first received unread character
value -1: indicates no character was received

The function USBD_CDC_ACM_GetChar reads a data character from the intermediate buffer that was received from the USB Host by the CDC device instance that is specified by the argument instance.

usbStatus USBD_CDC_ACM_Notify	(	uint8_t	instance,
		uint16_t	state
	)

Send notification of Communication Device status and line states to USB Host.

Parameters

[in]	instance	instance of CDC class.
[in]	state	error status and line states: bit 6: bOverRun bit 5: bParity bit 4: bFraming bit 3: bRingSignal bit 2: bBreak bit 1: bTxCarrier (DSR line state) bit 0: bRxCarrier (DCD line state)

Returns: status code that indicates the execution status of the function as defined with usbStatus.

The function USBD_CDC_ACM_Notify sends error and line status information about the Virtual COM Port over the Interrupt Endpoint.

The argument instance specifies the CDC device that is to be used with USBD_CDC_ACM_Notify.

The argument state specifies the error status and the line state.

Note: Bits 0 (bRxCarrier) and 1 (bTxCarrier) are consistent states signals and notify should be called whenever their state changes. For all other bits the notify should be called only when respective state has been activated or error has occurred.

int USBD_CDC_ACM_PutChar	(	uint8_t	instance,
		int	ch
	)

Write a single character from Communication Device to USB Host.

Parameters

[in]	instance	instance of CDC class.
[in]	ch	character to write.

Returns

value of accepted character or no character accepted.

value ch: if character accepted for writing
value -1: indicates character not accepted

The function USBD_CDC_ACM_PutChar asynchronously prepares a data byte that will be returned to the USB Host upon request.

The argument instance specifies the CDC class instance that is to be used.

The argument ch represents the character to be written.

int32_t USBD_CDC_ACM_ReadData	(	uint8_t	instance,
		uint8_t *	buf,
		int32_t	len
	)

Read multiple data bytes received by Communication Device from USB Host.

Parameters

[in]	instance	instance of CDC class.
[out]	buf	buffer that receives data.
[in]	len	maximum number of bytes to read.

Returns

number of bytes read or execution status.

value >= 0: number of bytes read
value < 0: error occurred, -value is execution status as defined with usbStatus

The function USBD_CDC_ACM_ReadData reads data from the intermediate buffer that was received from the USB Host and stores them into a buffer.

The argument instance specifies the CDC class instance that is to be used.

The argument buf is a pointer to the buffer where received data will be stored.

The argument len specifies the number of bytes to be read.

int32_t USBD_CDC_ACM_WriteData	(	uint8_t	instance,
		const uint8_t *	buf,
		int32_t	len
	)

Write data from Communication Device to USB Host.

Parameters

[in]	instance	instance of CDC class.
[in]	buf	buffer containing data bytes to write.
[in]	len	maximum number of bytes to write.

Returns

number of bytes accepted for writing or execution status.

value >= 0: number of bytes accepted for writing
value < 0: error occurred, -value is execution status as defined with usbStatus

The function USBD_CDC_ACM_WriteData asynchronously prepares data that will be returned to the USB Host upon request.

The argument instance specifies the CDC class instance that is to be used.

The argument buf is a pointer to the buffer containing the data to be written.

The argument len specifies the number of bytes to be written.

void USBD_CDCn_ACM_DataReceived ( uint32_t len )

Called when new data was received.

Parameters

[in] len number of bytes available to read.

Returns: none.

The function USBD_CDCn_ACM_DataReceived notifies that there is newly received data available.

The argument len is number of bytes available to read.

Modify this function to the application needs.

Note: Callback when new data is received on Bulk OUT Endpoint.

void USBD_CDCn_ACM_DataSent ( void )

Called when all data was sent.

Returns: none.

The function USBD_CDCn_ACM_DataSent notifies that all data was sent.

Note: Callback when all data was sent on Bulk IN Endpoint.

bool USBD_CDCn_ACM_GetLineCoding ( CDC_LINE_CODING * line_coding )

Called upon USB Host request to retrieve communication settings.

Parameters

[out] line_coding pointer to CDC_LINE_CODING structure.

Returns: true get line coding request processed.; false get line coding request not supported or not processed.

The function USBD_CDCn_ACM_GetLineCoding retrieves communication settings of the port used as the Virtual COM Port.

The argument line_coding is a pointer to the CDC Line Coding structure containing coding settings.

Modify this function to the application needs.

Note: Callback when Get Line Coding request comes on Control Endpoint 0.

void USBD_CDCn_ACM_Initialize ( void )

Called during USBD_Initialize to initialize the USB CDC class instance (ACM)

Returns: none.

The function USBD_CDCn_ACM_Initialize initializes the hardware resources of the port used as the Virtual COM Port. It is called during USBD_Initialize. The function may be used to allocate resources and initialize peripherals.

Modify this function to the application's needs.

Note: Remember to release used resources and de-initialize peripherals using USBD_CDCn_ACM_Uninitialize.

Code Example
The following code initializes an UART that is mapped as the Virtual COM Port to the CDC class.

bool USBD_CDCn_ACM_Initialize (void) {
 
  UART_Initialize ();
}  

void USBD_CDCn_ACM_Reset ( void )

Called upon USB Bus Reset Event.

Returns: none.

The function USBD_CDCn_ACM_Reset resets the internal states of the port used as the Virtual COM Port.

Modify this function to the application's needs.

Code Example
The following code resets an UART that is mapped as the Virtual COM Port to the CDC class.

void USBD_CDCn_ACM_Reset (void) {
 
  UART_Reset ();
}  

bool USBD_CDCn_ACM_SetControlLineState ( uint16_t state )

Called upon USB Host request to set control line states.

Parameters

[in]

state

control line settings bitmap.

bit 0: DTR state
bit 1: RTS state

Returns: true set control line state request processed.; false set control line state request not supported or not processed.

The function USBD_CDCn_ACM_SetControlLineState sets control line state on the port used as the Virtual COM Port.

The argument state represents control signal bitmap (0. bit - DTR line state, 1. bit - RTS line state).

Modify this function to the application needs.

Note: Callback when Set Control Line State request comes on Control Endpoint 0.

Code Example
The following code outputs the line state to LEDs.

void USBD_CDCn_ACM_SetControlLineState (uint16_t state) {
 
  ((state & 1) ? (LED_On (0)) : (LED_Off (0)));
  ((state & 2) ? (LED_On (1)) : (LED_Off (1)));
 
  return true;
}

bool USBD_CDCn_ACM_SetLineCoding ( CDC_LINE_CODING * line_coding )

Called upon USB Host request to change communication settings.

Parameters

[in] line_coding pointer to CDC_LINE_CODING structure.

Returns: true set line coding request processed.; false set line coding request not supported or not processed.

The function USBD_CDCn_ACM_SetLineCoding changes communication settings of the port used as the Virtual COM Port.

The argument line_coding is a pointer to the CDC Line Coding structure containing the requested coding settings.

Modify this function to the application needs.

Note: Callback when Set Line Coding request comes on Control Endpoint 0.

Code Example
The following code configures an UART that is mapped as the Virtual COM Port to the CDC class.

void USBD_CDCn_ACM_SetLineCoding (CDC_LINE_CODING *line_coding) {
 
  UART_Config.Baudrate    = line_coding->dwDTERate;
  UART_Config.DataBits    = (UART_DataBits) line_coding->bDataBits;
  UART_Config.Parity      = (UART_Parity)   line_coding->bParityType;
  UART_Config.StopBits    = (UART_StopBits) line_coding->bCharFormat;
  UART_Config.FlowControl = UART_FLOW_CONTROL_RTS_CTS;
 
  return true;
}

void USBD_CDCn_ACM_Uninitialize ( void )

Called during USBD_Uninitialize to de-initialize the USB CDC class instance (ACM)

Returns: none.

The function USBD_CDCn_ACM_Uninitialize de-initializes/releases the hardware resources of the port used as the Virtual COM Port. It is called during USBD_Uninitialize. If USBD_CDCn_ACM_Initialize has been adapted to the application, USBD_CDCn_ACM_Uninitialize should release resources and should de-initialize peripherals.

Code Example

bool USBD_CDCn_ACM_Uninitialize (void) {
 
  UART_Uninitialize ();
}

Functions

Description

Function Documentation