UART Interface. More...

Data Structures
struct	uart_event_tx
	UART TX event data. More...

struct	uart_event_rx
	UART RX event data. More...

struct	uart_event_rx_buf
	UART RX buffer released event data. More...

struct	uart_event_rx_stop
	UART RX stopped data. More...

struct	uart_event
	Structure containing information about current event. More...

struct	uart_config
	UART controller configuration structure. More...

struct	uart_device_config
	UART device configuration. More...

struct	uart_driver_api
	Driver API structure. More...

Typedefs
typedef void(*	uart_callback_t) (const struct device dev, struct uart_event evt, void *user_data)
	Define the application callback function signature for uart_callback_set() function. More...

typedef void(*	uart_irq_callback_user_data_t) (const struct device dev, void user_data)
	Define the application callback function signature for uart_irq_callback_user_data_set() function. More...

typedef void(*	uart_irq_config_func_t) (const struct device *dev)
	For configuring IRQ on each individual UART device. More...

Enumerations
enum	uart_line_ctrl { UART_LINE_CTRL_BAUD_RATE = BIT(0) , UART_LINE_CTRL_RTS = BIT(1) , UART_LINE_CTRL_DTR = BIT(2) , UART_LINE_CTRL_DCD = BIT(3) , UART_LINE_CTRL_DSR = BIT(4) }
	Line control signals. More...

enum	uart_event_type { UART_TX_DONE , UART_TX_ABORTED , UART_RX_RDY , UART_RX_BUF_REQUEST , UART_RX_BUF_RELEASED , UART_RX_DISABLED , UART_RX_STOPPED }
	Types of events passed to callback in UART_ASYNC_API. More...

enum	uart_rx_stop_reason { UART_ERROR_OVERRUN = (1 << 0) , UART_ERROR_PARITY = (1 << 1) , UART_ERROR_FRAMING = (1 << 2) , UART_BREAK = (1 << 3) , UART_ERROR_COLLISION = (1 << 4) }
	Reception stop reasons. More...

enum	uart_config_parity { UART_CFG_PARITY_NONE , UART_CFG_PARITY_ODD , UART_CFG_PARITY_EVEN , UART_CFG_PARITY_MARK , UART_CFG_PARITY_SPACE }
	Parity modes. More...

enum	uart_config_stop_bits { UART_CFG_STOP_BITS_0_5 , UART_CFG_STOP_BITS_1 , UART_CFG_STOP_BITS_1_5 , UART_CFG_STOP_BITS_2 }
	Number of stop bits. More...

enum	uart_config_data_bits { UART_CFG_DATA_BITS_5 , UART_CFG_DATA_BITS_6 , UART_CFG_DATA_BITS_7 , UART_CFG_DATA_BITS_8 , UART_CFG_DATA_BITS_9 }
	Number of data bits. More...

enum	uart_config_flow_control { UART_CFG_FLOW_CTRL_NONE , UART_CFG_FLOW_CTRL_RTS_CTS , UART_CFG_FLOW_CTRL_DTR_DSR }
	Hardware flow control options. More...

Functions
static int	uart_callback_set (const struct device dev, uart_callback_t callback, void user_data)
	Set event handler function. More...

int	uart_tx (const struct device dev, const uint8_t buf, size_t len, int32_t timeout)
	Send given number of bytes from buffer through UART. More...

int	uart_tx_abort (const struct device *dev)
	Abort current TX transmission. More...

int	uart_rx_enable (const struct device dev, uint8_t buf, size_t len, int32_t timeout)
	Start receiving data through UART. More...

static int	uart_rx_buf_rsp (const struct device dev, uint8_t buf, size_t len)
	Provide receive buffer in response to uart_event_type::UART_RX_BUF_REQUEST event. More...

int	uart_rx_disable (const struct device *dev)
	Disable RX. More...

int	uart_err_check (const struct device *dev)
	Check whether an error was detected. More...

int	uart_poll_in (const struct device dev, unsigned char p_char)
	Poll the device for input. More...

void	uart_poll_out (const struct device *dev, unsigned char out_char)
	Output a character in polled mode. More...

int	uart_configure (const struct device dev, const struct uart_config cfg)
	Set UART configuration. More...

int	uart_config_get (const struct device dev, struct uart_config cfg)
	Get UART configuration. More...

static int	uart_fifo_fill (const struct device dev, const uint8_t tx_data, int size)
	Fill FIFO with data. More...

static int	uart_fifo_read (const struct device dev, uint8_t rx_data, const int size)
	Read data from FIFO. More...

void	uart_irq_tx_enable (const struct device *dev)
	Enable TX interrupt in IER. More...

void	uart_irq_tx_disable (const struct device *dev)
	Disable TX interrupt in IER. More...

static int	uart_irq_tx_ready (const struct device *dev)
	Check if UART TX buffer can accept a new char. More...

void	uart_irq_rx_enable (const struct device *dev)
	Enable RX interrupt. More...

void	uart_irq_rx_disable (const struct device *dev)
	Disable RX interrupt. More...

static int	uart_irq_tx_complete (const struct device *dev)
	Check if UART TX block finished transmission. More...

static int	uart_irq_rx_ready (const struct device *dev)
	Check if UART RX buffer has a received char. More...

void	uart_irq_err_enable (const struct device *dev)
	Enable error interrupt. More...

void	uart_irq_err_disable (const struct device *dev)
	Disable error interrupt. More...

int	uart_irq_is_pending (const struct device *dev)
	Check if any IRQs is pending. More...

int	uart_irq_update (const struct device *dev)
	Start processing interrupts in ISR. More...

static void	uart_irq_callback_user_data_set (const struct device dev, uart_irq_callback_user_data_t cb, void user_data)
	Set the IRQ callback function pointer. More...

static void	uart_irq_callback_set (const struct device *dev, uart_irq_callback_user_data_t cb)
	Set the IRQ callback function pointer (legacy). More...

int	uart_line_ctrl_set (const struct device *dev, uint32_t ctrl, uint32_t val)
	Manipulate line control for UART. More...

int	uart_line_ctrl_get (const struct device dev, uint32_t ctrl, uint32_t val)
	Retrieve line control for UART. More...

int	uart_drv_cmd (const struct device *dev, uint32_t cmd, uint32_t p)
	Send extra command to driver. More...

Detailed Description

UART Interface.

Typedef Documentation

◆ uart_callback_t

uart_callback_t

#include <include/drivers/uart.h>

Define the application callback function signature for uart_callback_set() function.

Parameters

dev	UART device structure.
evt	Pointer to uart_event structure.
user_data	Pointer to data specified by user.

◆ uart_irq_callback_user_data_t

uart_irq_callback_user_data_t

#include <include/drivers/uart.h>

Define the application callback function signature for uart_irq_callback_user_data_set() function.

Parameters

dev	UART device structure.
user_data	Arbitrary user data.

◆ uart_irq_config_func_t

uart_irq_config_func_t

#include <include/drivers/uart.h>

For configuring IRQ on each individual UART device.

Parameters

dev	UART device structure.

Enumeration Type Documentation

◆ uart_config_data_bits

enum uart_config_data_bits

#include <include/drivers/uart.h>

Number of data bits.

Enumerator
UART_CFG_DATA_BITS_5
UART_CFG_DATA_BITS_6
UART_CFG_DATA_BITS_7
UART_CFG_DATA_BITS_8
UART_CFG_DATA_BITS_9

◆ uart_config_flow_control

enum uart_config_flow_control

#include <include/drivers/uart.h>

Hardware flow control options.

With flow control set to none, any operations related to flow control signals can be managed by user with uart_line_ctrl functions. In other cases, flow control is managed by hardware/driver.

Enumerator
UART_CFG_FLOW_CTRL_NONE
UART_CFG_FLOW_CTRL_RTS_CTS
UART_CFG_FLOW_CTRL_DTR_DSR

◆ uart_config_parity

enum uart_config_parity

#include <include/drivers/uart.h>

Parity modes.

Enumerator
UART_CFG_PARITY_NONE
UART_CFG_PARITY_ODD
UART_CFG_PARITY_EVEN
UART_CFG_PARITY_MARK
UART_CFG_PARITY_SPACE

◆ uart_config_stop_bits

enum uart_config_stop_bits

#include <include/drivers/uart.h>

Number of stop bits.

Enumerator
UART_CFG_STOP_BITS_0_5
UART_CFG_STOP_BITS_1
UART_CFG_STOP_BITS_1_5
UART_CFG_STOP_BITS_2

◆ uart_event_type

enum uart_event_type

#include <include/drivers/uart.h>

Types of events passed to callback in UART_ASYNC_API.

Receiving:

To start receiving, uart_rx_enable has to be called with first buffer
When receiving starts to current buffer, uart_event_type::UART_RX_BUF_REQUEST will be generated, in response to that user can either:
- Provide second buffer using uart_rx_buf_rsp, when first buffer is filled, receiving will automatically start to second buffer.
- Ignore the event, this way when current buffer is filled uart_event_type::UART_RX_RDY event will be generated and receiving will be stopped.
If some data was received and timeout occurred uart_event_type::UART_RX_RDY event will be generated. It can happen multiples times for the same buffer. RX timeout is counted from last byte received i.e. if no data was received, there won't be any timeout event.
After buffer is filled uart_event_type::UART_RX_RDY will be generated, immediately followed by uart_event_type::UART_RX_BUF_RELEASED indicating that current buffer is no longer used.
If there was second buffer provided, it will become current buffer and we start again at point 2. If no second buffer was specified receiving is stopped and uart_event_type::UART_RX_DISABLED event is generated. After that whole process can be repeated.

Any time during reception uart_event_type::UART_RX_STOPPED event can occur. if there is any data received, uart_event_type::UART_RX_RDY event will be generated. It will be followed by uart_event_type::UART_RX_BUF_RELEASED event for every buffer currently passed to driver and finally by uart_event_type::UART_RX_DISABLED event.

Receiving can be disabled using uart_rx_disable, after calling that function, if there is any data received, uart_event_type::UART_RX_RDY event will be generated. uart_event_type::UART_RX_BUF_RELEASED event will be generated for every buffer currently passed to driver and finally uart_event_type::UART_RX_DISABLED event will occur.

Transmitting:

Transmitting starts by uart_tx function.
If whole buffer was transmitted uart_event_type::UART_TX_DONE is generated. If timeout occurred uart_event_type::UART_TX_ABORTED will be generated.

Transmitting can be aborted using uart_tx_abort, after calling that function uart_event_type::UART_TX_ABORTED event will be generated.

Enumerator
UART_TX_DONE	Whole TX buffer was transmitted.
UART_TX_ABORTED	Transmitting aborted due to timeout or uart_tx_abort call. When flow control is enabled, there is a possibility that TX transfer won't finish in the allotted time. Some data may have been transferred, information about it can be found in event data.
UART_RX_RDY	Received data is ready for processing. This event is generated in the following cases: When RX timeout occurred, and data was stored in provided buffer. This can happen multiple times in the same buffer. When provided buffer is full. After uart_rx_disable(). After stopping due to external event (uart_event_type::UART_RX_STOPPED).
UART_RX_BUF_REQUEST	Driver requests next buffer for continuous reception. This event is triggered when receiving has started for a new buffer, i.e. it's time to provide a next buffer for a seamless switchover to it. For continuous reliable receiving, user should provide another RX buffer in response to this event, using uart_rx_buf_rsp function If uart_rx_buf_rsp is not called before current buffer is filled up, receiving will stop.
UART_RX_BUF_RELEASED	Buffer is no longer used by UART driver.
UART_RX_DISABLED	RX has been disabled and can be reenabled. This event is generated whenever receiver has been stopped, disabled or finished its operation and can be enabled again using uart_rx_enable
UART_RX_STOPPED	RX has stopped due to external event. Reason is one of uart_rx_stop_reason.

◆ uart_line_ctrl

enum uart_line_ctrl

#include <include/drivers/uart.h>

Line control signals.

Enumerator
UART_LINE_CTRL_BAUD_RATE
UART_LINE_CTRL_RTS
UART_LINE_CTRL_DTR
UART_LINE_CTRL_DCD
UART_LINE_CTRL_DSR

◆ uart_rx_stop_reason

enum uart_rx_stop_reason

#include <include/drivers/uart.h>

Reception stop reasons.

Values that correspond to events or errors responsible for stopping receiving.

Enumerator
UART_ERROR_OVERRUN	Overrun error.
UART_ERROR_PARITY	Parity error.
UART_ERROR_FRAMING	Framing error.
UART_BREAK	Break interrupt. A break interrupt was received. This happens when the serial input is held at a logic '0' state for longer than the sum of start time + data bits + parity + stop bits.
UART_ERROR_COLLISION	Collision error. This error is raised when transmitted data does not match received data. Typically this is useful in scenarios where the TX and RX lines maybe connected together such as RS-485 half-duplex. This error is only valid on UARTs that support collision checking.

Function Documentation

◆ uart_callback_set()

static int uart_callback_set	(	const struct device *	dev,
		uart_callback_t	callback,
		void *	user_data
	)

inlinestatic

#include <include/drivers/uart.h>

Set event handler function.

Parameters

dev	UART device structure.
callback	Event handler.
user_data	Data to pass to event handler function.

Return values

-ENOTSUP	If not supported.
0	If successful, negative errno code otherwise.

◆ uart_config_get()

int uart_config_get	(	const struct device *	dev,
		struct uart_config *	cfg
	)

#include <include/drivers/uart.h>

Get UART configuration.

Stores current UART configuration to *cfg, can be used to retrieve initial configuration after device was initialized using data from DTS.

Parameters

dev	UART device structure.
cfg	UART configuration structure.

Return values

-ENOTSUP	If driver does not support getting current configuration.
0	If successful, negative errno code otherwise.

◆ uart_configure()

int uart_configure	(	const struct device *	dev,
		const struct uart_config *	cfg
	)

#include <include/drivers/uart.h>

Set UART configuration.

Sets UART configuration using data from *cfg.

Parameters

dev	UART device structure.
cfg	UART configuration structure.

Return values

-ENOSYS	If configuration is not supported by device. or driver does not support setting configuration in runtime.
0	If successful, negative errno code otherwise.

◆ uart_drv_cmd()

int uart_drv_cmd	(	const struct device *	dev,
		uint32_t	cmd,
		uint32_t	p
	)

#include <include/drivers/uart.h>

Send extra command to driver.

Implementation and accepted commands are driver specific. Refer to the drivers for more information.

Parameters

dev	UART device structure.
cmd	Command to driver.
p	Parameter to the command.

Return values

0	If successful.
failed	Otherwise.

◆ uart_err_check()

int uart_err_check ( const struct device * dev )

#include <include/drivers/uart.h>

Check whether an error was detected.

Parameters

dev	UART device structure.

Return values

uart_rx_stop_reason	If error during receiving occurred.
0	Otherwise.

◆ uart_fifo_fill()

static int uart_fifo_fill	(	const struct device *	dev,
		const uint8_t *	tx_data,
		int	size
	)

inlinestatic

#include <include/drivers/uart.h>

Fill FIFO with data.

This function is expected to be called from UART interrupt handler (ISR), if uart_irq_tx_ready() returns true. Result of calling this function not from an ISR is undefined (hardware-dependent). Likewise, not calling this function from an ISR if uart_irq_tx_ready() returns true may lead to undefined behavior, e.g. infinite interrupt loops. It's mandatory to test return value of this function, as different hardware has different FIFO depth (oftentimes just 1).

Parameters

dev	UART device structure.
tx_data	Data to transmit.
size	Number of bytes to send.

Returns: Number of bytes sent.

◆ uart_fifo_read()

static int uart_fifo_read	(	const struct device *	dev,
		uint8_t *	rx_data,
		const int	size
	)

inlinestatic

#include <include/drivers/uart.h>

Read data from FIFO.

This function is expected to be called from UART interrupt handler (ISR), if uart_irq_rx_ready() returns true. Result of calling this function not from an ISR is undefined (hardware-dependent). It's unspecified whether "RX ready" condition as returned by uart_irq_rx_ready() is level- or edge- triggered. That means that once uart_irq_rx_ready() is detected, uart_fifo_read() must be called until it reads all available data in the FIFO (i.e. until it returns less data than was requested).

Note that the calling context only applies to physical UARTs and no to the virtual ones found in USB CDC ACM code.

Parameters

dev	UART device structure.
rx_data	Data container.
size	Container size.

Returns: Number of bytes read.

◆ uart_irq_callback_set()

static void uart_irq_callback_set	(	const struct device *	dev,
		uart_irq_callback_user_data_t	cb
	)

inlinestatic

#include <include/drivers/uart.h>

Set the IRQ callback function pointer (legacy).

This sets up the callback for IRQ. When an IRQ is triggered, the specified function will be called with the device pointer.

Parameters

dev	UART device structure.
cb	Pointer to the callback function.

Returns: N/A

◆ uart_irq_callback_user_data_set()

static void uart_irq_callback_user_data_set	(	const struct device *	dev,
		uart_irq_callback_user_data_t	cb,
		void *	user_data
	)

inlinestatic

#include <include/drivers/uart.h>

Set the IRQ callback function pointer.

This sets up the callback for IRQ. When an IRQ is triggered, the specified function will be called with specified user data. See description of uart_irq_update() for the requirements on ISR.

Parameters

dev	UART device structure.
cb	Pointer to the callback function.
user_data	Data to pass to callback function.

Returns: N/A

◆ uart_irq_err_disable()

void uart_irq_err_disable ( const struct device * dev )

#include <include/drivers/uart.h>

Disable error interrupt.

Parameters

dev	UART device structure.

Return values

1	If an IRQ is ready.
0	Otherwise.

◆ uart_irq_err_enable()

void uart_irq_err_enable ( const struct device * dev )

#include <include/drivers/uart.h>

Enable error interrupt.

Parameters

dev	UART device structure.

Returns: N/A

◆ uart_irq_is_pending()

int uart_irq_is_pending ( const struct device * dev )

#include <include/drivers/uart.h>

Check if any IRQs is pending.

Parameters

dev	UART device structure.

Return values

1	If an IRQ is pending.
0	Otherwise.

◆ uart_irq_rx_disable()

void uart_irq_rx_disable ( const struct device * dev )

#include <include/drivers/uart.h>

Disable RX interrupt.

Parameters

dev	UART device structure.

Returns: N/A

◆ uart_irq_rx_enable()

void uart_irq_rx_enable ( const struct device * dev )

#include <include/drivers/uart.h>

Enable RX interrupt.

Parameters

dev	UART device structure.

Returns: N/A

◆ uart_irq_rx_ready()

static int uart_irq_rx_ready ( const struct device * dev )

inlinestatic

#include <include/drivers/uart.h>

Check if UART RX buffer has a received char.

Check if UART RX buffer has at least one pending character (i.e. uart_fifo_read() will succeed and return non-zero). This function must be called in a UART interrupt handler, or its result is undefined. Before calling this function in the interrupt handler, uart_irq_update() must be called once per the handler invocation. It's unspecified whether condition as returned by this function is level- or edge- triggered (i.e. if this function returns true when RX FIFO is non-empty, or when a new char was received since last call to it). See description of uart_fifo_read() for implication of this.

Parameters

dev	UART device structure.

Return values

1	If a received char is ready.
0	Otherwise.
-ENOTSUP	if this function is not supported

◆ uart_irq_tx_complete()

static int uart_irq_tx_complete ( const struct device * dev )

inlinestatic

#include <include/drivers/uart.h>

Check if UART TX block finished transmission.

Check if any outgoing data buffered in UART TX block was fully transmitted and TX block is idle. When this condition is true, UART device (or whole system) can be power off. Note that this function is not useful to check if UART TX can accept more data, use uart_irq_tx_ready() for that. This function must be called in a UART interrupt handler, or its result is undefined. Before calling this function in the interrupt handler, uart_irq_update() must be called once per the handler invocation.

Parameters

dev	UART device structure.

Return values

1	If nothing remains to be transmitted.
0	Otherwise.
-ENOTSUP	if this function is not supported

◆ uart_irq_tx_disable()

void uart_irq_tx_disable ( const struct device * dev )

#include <include/drivers/uart.h>

Disable TX interrupt in IER.

Parameters

dev	UART device structure.

Returns: N/A

◆ uart_irq_tx_enable()

void uart_irq_tx_enable ( const struct device * dev )

#include <include/drivers/uart.h>

Enable TX interrupt in IER.

Parameters

dev	UART device structure.

Returns: N/A

◆ uart_irq_tx_ready()

static int uart_irq_tx_ready ( const struct device * dev )

inlinestatic

#include <include/drivers/uart.h>

Check if UART TX buffer can accept a new char.

Check if UART TX buffer can accept at least one character for transmission (i.e. uart_fifo_fill() will succeed and return non-zero). This function must be called in a UART interrupt handler, or its result is undefined. Before calling this function in the interrupt handler, uart_irq_update() must be called once per the handler invocation.

Parameters

dev	UART device structure.

Return values

1	If at least one char can be written to UART.
0	Otherwise.

◆ uart_irq_update()

int uart_irq_update ( const struct device * dev )

#include <include/drivers/uart.h>

Start processing interrupts in ISR.

This function should be called the first thing in the ISR. Calling uart_irq_rx_ready(), uart_irq_tx_ready(), uart_irq_tx_complete() allowed only after this.

The purpose of this function is:

For devices with auto-acknowledge of interrupt status on register read to cache the value of this register (rx_ready, etc. then use this case).
For devices with explicit acknowledgement of interrupts, to ack any pending interrupts and likewise to cache the original value.
For devices with implicit acknowledgement, this function will be empty. But the ISR must perform the actions needs to ack the interrupts (usually, call uart_fifo_read() on rx_ready, and uart_fifo_fill() on tx_ready).

Parameters

dev	UART device structure.

Return values

1 Always.

◆ uart_line_ctrl_get()

int uart_line_ctrl_get	(	const struct device *	dev,
		uint32_t	ctrl,
		uint32_t *	val
	)

#include <include/drivers/uart.h>

Retrieve line control for UART.

Parameters

dev	UART device structure.
ctrl	The line control to retrieve (see enum uart_line_ctrl).
val	Pointer to variable where to store the line control value.

Return values

0	If successful.
failed	Otherwise.

◆ uart_line_ctrl_set()

int uart_line_ctrl_set	(	const struct device *	dev,
		uint32_t	ctrl,
		uint32_t	val
	)

#include <include/drivers/uart.h>

Manipulate line control for UART.

Parameters

dev	UART device structure.
ctrl	The line control to manipulate (see enum uart_line_ctrl).
val	Value to set to the line control.

Return values

0	If successful.
failed	Otherwise.

◆ uart_poll_in()

int uart_poll_in	(	const struct device *	dev,
		unsigned char *	p_char
	)

#include <include/drivers/uart.h>

Poll the device for input.

Parameters

dev	UART device structure.
p_char	Pointer to character.

Return values

0	If a character arrived.
-1	If no character was available to read (i.e., the UART input buffer was empty).
-ENOTSUP	If the operation is not supported.
-EBUSY	If reception was enabled using uart_rx_enabled

◆ uart_poll_out()

void uart_poll_out	(	const struct device *	dev,
		unsigned char	out_char
	)

#include <include/drivers/uart.h>

Output a character in polled mode.

This routine checks if the transmitter is empty. When the transmitter is empty, it writes a character to the data register.

To send a character when hardware flow control is enabled, the handshake signal CTS must be asserted.

Parameters

dev	UART device structure.
out_char	Character to send.

◆ uart_rx_buf_rsp()

static int uart_rx_buf_rsp	(	const struct device *	dev,
		uint8_t *	buf,
		size_t	len
	)

inlinestatic

#include <include/drivers/uart.h>

Provide receive buffer in response to uart_event_type::UART_RX_BUF_REQUEST event.

Provide pointer to RX buffer, which will be used when current buffer is filled.

Note: Providing buffer that is already in usage by driver leads to undefined behavior. Buffer can be reused when it has been released by driver.

Parameters

dev	UART device structure.
buf	Pointer to receive buffer.
len	Buffer length.

Return values

-ENOTSUP	If not supported.
-EBUSY	Next buffer already set.
-EACCES	Receiver is already disabled (function called too late?).
0	If successful, negative errno code otherwise.

◆ uart_rx_disable()

int uart_rx_disable ( const struct device * dev )

#include <include/drivers/uart.h>

Disable RX.

uart_event_type::UART_RX_BUF_RELEASED event will be generated for every buffer scheduled, after that uart_event_type::UART_RX_DISABLED event will be generated. Additionally, if there is any pending received data, the uart_event_type::UART_RX_RDY event for that data will be generated before the uart_event_type::UART_RX_BUF_RELEASED events.

Parameters

dev	UART device structure.

Return values

-ENOTSUP	If not supported.
-EFAULT	There is no active reception.
0	If successful, negative errno code otherwise.

◆ uart_rx_enable()

int uart_rx_enable	(	const struct device *	dev,
		uint8_t *	buf,
		size_t	len,
		int32_t	timeout
	)

#include <include/drivers/uart.h>

Start receiving data through UART.

Function sets given buffer as first buffer for receiving and returns immediately. After that event handler, set using uart_callback_set, is called with uart_event_type::UART_RX_RDY or uart_event_type::UART_RX_BUF_REQUEST events.

Parameters

dev	UART device structure.
buf	Pointer to receive buffer.
len	Buffer length.
timeout	Inactivity period after receiving at least a byte which triggers uart_event_type::UART_RX_RDY event. Given in milliseconds. SYS_FOREVER_MS disables timeout. See uart_event_type for details.

Return values

-ENOTSUP	If not supported.
-EBUSY	RX already in progress.
0	If successful, negative errno code otherwise.

◆ uart_tx()

int uart_tx	(	const struct device *	dev,
		const uint8_t *	buf,
		size_t	len,
		int32_t	timeout
	)

#include <include/drivers/uart.h>

Send given number of bytes from buffer through UART.

Function returns immediately and event handler, set using uart_callback_set, is called after transfer is finished.

Parameters

dev	UART device structure.
buf	Pointer to transmit buffer.
len	Length of transmit buffer.
timeout	Timeout in milliseconds. Valid only if flow control is enabled. SYS_FOREVER_MS disables timeout.

Return values

-ENOTSUP	If not supported.
-EBUSY	There is already an ongoing transfer.
0	If successful, negative errno code otherwise.

◆ uart_tx_abort()

int uart_tx_abort ( const struct device * dev )

#include <include/drivers/uart.h>

Abort current TX transmission.

uart_event_type::UART_TX_DONE event will be generated with amount of data sent.

Parameters

dev	UART device structure.

Return values

-ENOTSUP	If not supported.
-EFAULT	There is no active transmission.
0	If successful, negative errno code otherwise.

Data Structures

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ uart_callback_t

◆ uart_irq_callback_user_data_t

◆ uart_irq_config_func_t

Enumeration Type Documentation

◆ uart_config_data_bits

◆ uart_config_flow_control

◆ uart_config_parity

◆ uart_config_stop_bits

◆ uart_event_type

◆ uart_line_ctrl

◆ uart_rx_stop_reason

Function Documentation

◆ uart_callback_set()

◆ uart_config_get()

◆ uart_configure()

◆ uart_drv_cmd()

◆ uart_err_check()

◆ uart_fifo_fill()

◆ uart_fifo_read()

◆ uart_irq_callback_set()

◆ uart_irq_callback_user_data_set()

◆ uart_irq_err_disable()

◆ uart_irq_err_enable()

◆ uart_irq_is_pending()

◆ uart_irq_rx_disable()

◆ uart_irq_rx_enable()

◆ uart_irq_rx_ready()

◆ uart_irq_tx_complete()

◆ uart_irq_tx_disable()

◆ uart_irq_tx_enable()

◆ uart_irq_tx_ready()

◆ uart_irq_update()

◆ uart_line_ctrl_get()

◆ uart_line_ctrl_set()

◆ uart_poll_in()

◆ uart_poll_out()

◆ uart_rx_buf_rsp()

◆ uart_rx_disable()

◆ uart_rx_enable()

◆ uart_tx()

◆ uart_tx_abort()