USB Host Interface (UHI) for Communication Class Device (CDC) provides an interface for the configuration and management of USB CDC serial host.

The outline of this documentation is as follows:

For more details for Atmel® Software Framework (ASF) USB Host Stack, refer to following application note:

AVR4950: ASF - USB Host Stack

API Overview

Interface with USB Host Core (UHC)
Definition and functions required by UHC.
#define	UHI_CDC
	Global definition which contains standard UHI API for UHC. More...

Functions Required by UHC
uhc_enum_status_t	uhi_cdc_install (uhc_device_t *dev)
	Install interface. More...

void	uhi_cdc_enable (uhc_device_t *dev)
	Enable the interface. More...

void	uhi_cdc_uninstall (uhc_device_t *dev)
	Uninstall the interface (if installed). More...

void	uhi_cdc_sof (bool b_micro)
	Signal that a SOF has occurred. More...

UHI for Communication Device Class
Common APIs used by high level application to use this USB host class. These routines are used by memory to transfer its data to/from USB CDC endpoint.
bool	uhi_cdc_open (uint8_t port, usb_cdc_line_coding_t *configuration)
	Open a port of UHI CDC interface. More...

void	uhi_cdc_close (uint8_t port)
	Close a port. More...

bool	uhi_cdc_is_rx_ready (uint8_t port)
	This function checks if a character has been received on the CDC line. More...

iram_size_t	uhi_cdc_get_nb_received (uint8_t port)
	This function returns the number of character available on the CDC line. More...

int	uhi_cdc_getc (uint8_t port)
	Waits and gets a value on CDC line. More...

iram_size_t	uhi_cdc_read_buf (uint8_t port, void *buf, iram_size_t size)
	Reads a RAM buffer on CDC line. More...

bool	uhi_cdc_is_tx_ready (uint8_t port)
	This function checks if a new character sent is possible. More...

int	uhi_cdc_putc (uint8_t port, int value)
	Puts a byte on CDC line. More...

iram_size_t	uhi_cdc_write_buf (uint8_t port, const void *buf, iram_size_t size)
	Writes a RAM buffer on CDC line. More...

#define UHI_CDC

Value:

{ \
    .install = uhi_cdc_install, \
    .enable = uhi_cdc_enable, \
    .uninstall = uhi_cdc_uninstall, \
    .sof_notify = uhi_cdc_sof, \
}

Global definition which contains standard UHI API for UHC.

It must be added in USB_HOST_UHI define from conf_usb_host.h file.

void uhi_cdc_close ( uint8_t port )

Close a port.

Parameters

[in] port Communication port number

void uhi_cdc_enable ( uhc_device_t * dev )

Enable the interface.

Enable a USB interface corresponding to UHI.

Parameters

[in] uhc_device_t Device to request

iram_size_t uhi_cdc_get_nb_received ( uint8_t port )

This function returns the number of character available on the CDC line.

Parameters

[in] port Communication port number

Returns: The number of data received.

int uhi_cdc_getc ( uint8_t port )

Waits and gets a value on CDC line.

Parameters

[in] port Communication port number

Returns: Value read on CDC line.

uhc_enum_status_t uhi_cdc_install ( uhc_device_t * dev )

Install interface.

Allocate interface endpoints if supported.

Parameters

[in] uhc_device_t Device to request

Returns: Status of the install.

bool uhi_cdc_is_rx_ready ( uint8_t port )

This function checks if a character has been received on the CDC line.

Parameters

[in] port Communication port number

Returns: true if a byte is ready to be read.

bool uhi_cdc_is_tx_ready ( uint8_t port )

This function checks if a new character sent is possible.

The type int is used to support scanf redirection from compiler LIB.

Parameters

[in] port Communication port number

Returns: true if a new character can be sent.

bool uhi_cdc_open	(	uint8_t	port,
		usb_cdc_line_coding_t *	configuration
	)

Open a port of UHI CDC interface.

Parameters

[in]	port	Communication port number
[in]	configuration	Pointer on port configuration

Returns: true if the port is available.

int uhi_cdc_putc	(	uint8_t	port,
		int	value
	)

Puts a byte on CDC line.

The type int is used to support printf redirection from compiler LIB.

Parameters

[in]	port	Communication port number
[in]	value	Value to put

Returns: true if function was successfully done, otherwise false.

iram_size_t uhi_cdc_read_buf	(	uint8_t	port,
		void *	buf,
		iram_size_t	size
	)

Reads a RAM buffer on CDC line.

Parameters

[in]	port	Communication port number
[out]	buf	Values read
[in]	size	Number of value read

Returns: The number of data remaining.

void uhi_cdc_sof ( bool b_micro )

Signal that a SOF has occurred.

void uhi_cdc_uninstall ( uhc_device_t * dev )

Uninstall the interface (if installed).

Parameters

[in] uhc_device_t Device to request

iram_size_t uhi_cdc_write_buf	(	uint8_t	port,
		const void *	buf,
		iram_size_t	size
	)

Writes a RAM buffer on CDC line.

Parameters

[in]	port	Communication port number
[in]	buf	Values to write
[in]	size	Number of value to write

Returns: The number of data remaining.

Microchip® Advanced Software Framework

API Overview

Interface with USB Host Core (UHC)

Functions Required by UHC

UHI for Communication Device Class