Class for sending AT commands and parsing AT responses. More...

#include <ATHandler.h>

Public Member Functions
	ATHandler (FileHandle fh, events::EventQueue &queue, uint32_t timeout, const char output_delimiter, uint16_t send_delay=0)
	Constructor. More...

	ATHandler (FileHandle fh, events::EventQueue &queue, mbed::chrono::milliseconds_u32 timeout, const char output_delimiter, std::chrono::duration< uint16_t, std::milli > send_delay=std::chrono::milliseconds(0))
	Constructor. More...

FileHandle *	get_file_handle ()
	Return used file handle. More...

void	lock ()
	Locks the mutex for file handle if AT_HANDLER_MUTEX is defined. More...

void	unlock ()
	Unlocks the mutex for file handle if AT_HANDLER_MUTEX is defined. More...

nsapi_error_t	unlock_return_error ()
	Locks the mutex for file handle if AT_HANDLER_MUTEX is defined and returns the last error. More...

void	set_urc_handler (const char *prefix, Callback< void()> callback)
	Set callback function for URC. More...

nsapi_error_t	get_last_error () const
	returns the last error while parsing AT responses. More...

device_err_t	get_last_device_error () const
	returns the last device error while parsing AT responses. More...

void	set_at_timeout (uint32_t timeout_milliseconds, bool default_timeout=false)
	Set timeout in milliseconds for AT commands. More...

void	set_at_timeout (mbed::chrono::milliseconds_u32 timeout, bool default_timeout=false)
	Set timeout in milliseconds for AT commands. More...

void	restore_at_timeout ()
	Restore timeout to previous timeout. More...

void	clear_error ()
	Clear pending error flag. More...

void	flush ()
	Flushes the underlying stream. More...

void	process_oob ()
	Tries to find oob's from the AT response. More...

void	set_is_filehandle_usable (bool usable)
	Set is file handle usable. More...

bool	sync (int timeout_ms)
	Synchronize AT command and response handling to modem. More...

bool	sync (std::chrono::duration< int, std::milli > timeout)
	Synchronize AT command and response handling to modem. More...

void	set_send_delay (uint16_t send_delay)
	Sets the delay to be applied before sending any AT command. More...

void	set_baud (int baud_rate)
	Sets BufferedSerial filehandle to given baud rate. More...

void	cmd_start (const char *cmd)
	Starts the command writing by clearing the last error and writing the given command. More...

void	cmd_start_stop (const char cmd, const char cmd_chr, const char *format="",...)
	cmd_start_stop Starts an AT command, writes given variadic arguments and stops the command. More...

nsapi_error_t	at_cmd_str (const char cmd, const char cmd_chr, char resp_buf, size_t resp_buf_size, const char format="",...)
	at_cmd_str Send an AT command and read a single string response. More...

nsapi_error_t	at_cmd_int (const char cmd, const char cmd_chr, int &resp, const char *format="",...)
	at_cmd_int Send an AT command and read a single integer response. More...

nsapi_error_t	at_cmd_discard (const char cmd, const char cmd_chr, const char *format="",...)
	at_cmd_discard Send an AT command and read and discard a response. More...

void	write_int (int32_t param)
	Writes integer type AT command subparameter. More...

void	write_string (const char *param, bool useQuotations=true)
	Writes string type AT command subparamater. More...

void	cmd_stop ()
	Stops the AT command by writing command-line terminator CR to mark command as finished. More...

void	cmd_stop_read_resp ()
	Stops the AT command by writing command-line terminator CR to mark command as finished and reads the OK/ERROR response. More...

size_t	write_bytes (const uint8_t *data, size_t len)
	Write bytes without any subparameter delimiters, such as comma. More...

void	set_stop_tag (const char *stop_tag_seq)
	Sets the stop tag for the current scope (response/information response/element) Parameter's reading routines will stop the reading when such tag is found and will set the found flag. More...

void	set_delimiter (char delimiter)
	Sets the delimiter between parameters or between elements of the information response. More...

void	set_default_delimiter ()
	Sets the delimiter to default value defined by DEFAULT_DELIMITER. More...

void	use_delimiter (bool use_delimiter)
	Defines behaviour for using or ignoring the delimiter within an AT command. More...

void	skip_param (uint32_t count=1)
	Consumes the reading buffer up to the delimiter or stop_tag. More...

void	skip_param (ssize_t len, uint32_t count)
	Consumes the given length from the reading buffer. More...

void	skip_param_bytes (ssize_t len, uint32_t count)
	Consumes the given length from the reading buffer even if the stop tag has been found. More...

ssize_t	read_bytes (uint8_t *buf, size_t len)
	Reads given number of bytes from receiving buffer without checking any subparameter delimiters, such as comma. More...

ssize_t	read_string (char *str, size_t size, bool read_even_stop_tag=false)
	Reads chars from reading buffer. More...

ssize_t	read_hex_string (char *str, size_t size)
	Reads chars representing hex ascii values and converts them to the corresponding chars. More...

void	write_hex_string (const char *str, size_t size, bool quote_string=true)
	Converts contained chars to their hex ascii value and writes the resulting string to the file handle For example: "AV" to "4156". More...

int32_t	read_int ()
	Reads as string and converts result to integer. More...

void	resp_start (const char *prefix=NULL, bool stop=false)
	This looks for necessary matches: prefix, OK, ERROR, URCs and sets the correct scope. More...

void	resp_stop ()
	Ends all scopes starting from current scope. More...

bool	info_resp ()
	Looks for matching the prefix given to resp_start() call. More...

bool	info_elem (char start_tag)
	Looks for matching the start tag. More...

bool	consume_to_stop_tag ()
	Consumes the received content until current stop tag is found. More...

bool	consume_to_stop_tag_even_found ()
	Consumes the received content until current stop tag is found even if stop tag has been found previously. More...

int	get_3gpp_error ()
	Return the last 3GPP error code. More...

void	set_debug (bool debug_on)
	AT debugging, when enabled will print all data read and written, non-printable chars are printed as "[%d]". More...

bool	get_debug () const
	Get degug state set by set_debug. More...

Detailed Description

Class for sending AT commands and parsing AT responses.

Definition at line 68 of file ATHandler.h.

Constructor & Destructor Documentation

◆ ATHandler() [1/2]

ATHandler	(	FileHandle *	fh,
		events::EventQueue &	queue,
		uint32_t	timeout,
		const char *	output_delimiter,
		uint16_t	send_delay = `0`
	)

Constructor.

Parameters

fh	file handle used for reading AT responses and writing AT commands
queue	Event queue used to transfer sigio events to this thread
timeout	Timeout when reading for AT response
output_delimiter	delimiter used when parsing at responses, "\r" should be used as output_delimiter
send_delay	the minimum delay in ms between the end of last response and the beginning of a new command

◆ ATHandler() [2/2]

ATHandler	(	FileHandle *	fh,
		events::EventQueue &	queue,
		mbed::chrono::milliseconds_u32	timeout,
		const char *	output_delimiter,
		std::chrono::duration< uint16_t, std::milli >	send_delay = `std::chrono::milliseconds(0)`
	)

Constructor.

Parameters

fh	file handle used for reading AT responses and writing AT commands
queue	Event queue used to transfer sigio events to this thread
timeout	Timeout when reading for AT response
output_delimiter	delimiter used when parsing at responses, "\r" should be used as output_delimiter
send_delay	the minimum delay in ms between the end of last response and the beginning of a new command

Member Function Documentation

◆ get_file_handle()

FileHandle * get_file_handle ( )

Return used file handle.

Returns: used file handle

◆ lock()

void lock ( )

Locks the mutex for file handle if AT_HANDLER_MUTEX is defined.

◆ unlock()

void unlock ( )

Unlocks the mutex for file handle if AT_HANDLER_MUTEX is defined.

◆ unlock_return_error()

nsapi_error_t unlock_return_error ( )

Locks the mutex for file handle if AT_HANDLER_MUTEX is defined and returns the last error.

Returns: last error that happened when parsing AT responses

◆ set_urc_handler()

void set_urc_handler	(	const char *	prefix,
		Callback< void()>	callback
	)

Set callback function for URC.

Parameters

prefix	URC text to look for, e.g. "+CMTI:". Maximum length is MBED_CONF_CELLULAR_AT_HANDLER_BUFFER_SIZE.
callback	function to call on prefix, or 0 to remove callback

◆ get_last_error()

nsapi_error_t get_last_error ( ) const

returns the last error while parsing AT responses.

Returns: last error

◆ get_last_device_error()

device_err_t get_last_device_error ( ) const

returns the last device error while parsing AT responses.

Actually AT error (CME/CMS).

Returns: last error struct device_err_t

◆ set_at_timeout() [1/2]

void set_at_timeout	(	uint32_t	timeout_milliseconds,
		bool	default_timeout = `false`
	)

Set timeout in milliseconds for AT commands.

Parameters

timeout_milliseconds	Timeout in milliseconds
default_timeout	Store as default timeout

◆ set_at_timeout() [2/2]

void set_at_timeout	(	mbed::chrono::milliseconds_u32	timeout,
		bool	default_timeout = `false`
	)

Set timeout in milliseconds for AT commands.

Parameters

timeout	Timeout in milliseconds
default_timeout	Store as default timeout

◆ restore_at_timeout()

void restore_at_timeout ( )

Restore timeout to previous timeout.

Handy if there is a need to change timeout temporarily.

◆ clear_error()

void clear_error ( )

Clear pending error flag.

By default, error is cleared only in lock().

◆ flush()

void flush ( )

Flushes the underlying stream.

◆ process_oob()

void process_oob ( )

Tries to find oob's from the AT response.

Call the urc callback if one is found.

◆ set_is_filehandle_usable()

void set_is_filehandle_usable ( bool usable )

Set is file handle usable.

Some situations like after going to data mode, file handle is not usable anymore. Any items in queue are not to be processed.

Parameters

usable true for usable filehandle

◆ sync() [1/2]

bool sync ( int timeout_ms )

Synchronize AT command and response handling to modem.

Parameters

timeout_ms ATHandler timeout when trying to sync. Will be restored when function returns.

Returns: true is synchronization was successful, false in case of failure

◆ sync() [2/2]

bool sync ( std::chrono::duration< int, std::milli > timeout )

Synchronize AT command and response handling to modem.

Parameters

timeout ATHandler timeout when trying to sync. Will be restored when function returns.

Returns: true is synchronization was successful, false in case of failure

◆ set_send_delay()

void set_send_delay ( uint16_t send_delay )

Sets the delay to be applied before sending any AT command.

Parameters

send_delay the minimum delay in ms between the end of last response and the beginning of a new command

◆ set_baud()

void set_baud ( int baud_rate )

Sets BufferedSerial filehandle to given baud rate.

Parameters

baud_rate

◆ cmd_start()

void cmd_start ( const char * cmd )

Starts the command writing by clearing the last error and writing the given command.

In case of failure when writing, the last error is set to NSAPI_ERROR_DEVICE_ERROR.

Parameters

cmd	AT command to be written to modem

◆ cmd_start_stop()

void cmd_start_stop	(	const char *	cmd,
		const char *	cmd_chr,
		const char *	format = `""`,
			...
	)

cmd_start_stop Starts an AT command, writes given variadic arguments and stops the command.

Use this command when you need multiple response parameters to be handled. NOTE: Does not lock ATHandler for process!

Parameters

cmd	AT command in form +<CMD< (will be used also in response reading, no extra chars allowed)
cmd_chr	Char to be added to specific AT command: '?', '=' or ''. Will be used as such so '=1' is valid as well.
format	Format string for variadic arguments to be added to AT command; No separator needed. Use d for integer, s for string and b for byte string (requires 2 arguments: string and length)

◆ at_cmd_str()

nsapi_error_t at_cmd_str	(	const char *	cmd,
		const char *	cmd_chr,
		char *	resp_buf,
		size_t	resp_buf_size,
		const char *	format = `""`,
			...
	)

at_cmd_str Send an AT command and read a single string response.

Locks and unlocks ATHandler for operation

Parameters

cmd	AT command in form +<CMD< (will be used also in response reading, no extra chars allowed)
cmd_chr	Char to be added to specific AT command: '?', '=' or ''. Will be used as such so '=1' is valid as well.
resp_buf	Response buffer
resp_buf_size	Response buffer size
format	Format string for variadic arguments to be added to AT command; No separator needed. Use d for integer, s for string and b for byte string (requires 2 arguments: string and length)

Returns: last error that happened when parsing AT responses

◆ at_cmd_int()

nsapi_error_t at_cmd_int	(	const char *	cmd,
		const char *	cmd_chr,
		int &	resp,
		const char *	format = `""`,
			...
	)

at_cmd_int Send an AT command and read a single integer response.

Locks and unlocks ATHandler for operation

Parameters

cmd	AT command in form +<CMD< (will be used also in response reading, no extra chars allowed)
cmd_chr	Char to be added to specific AT command: '?', '=' or ''. Will be used as such so '=1' is valid as well.
resp	Integer to hold response
format	Format string for variadic arguments to be added to AT command; No separator needed. Use d for integer, s for string and b for byte string (requires 2 arguments: string and length)

Returns: last error that happened when parsing AT responses

◆ at_cmd_discard()

nsapi_error_t at_cmd_discard	(	const char *	cmd,
		const char *	cmd_chr,
		const char *	format = `""`,
			...
	)

at_cmd_discard Send an AT command and read and discard a response.

Locks and unlocks ATHandler for operation

Parameters

cmd	AT command in form +<CMD< (will be used also in response reading, no extra chars allowed)
cmd_chr	Char to be added to specific AT command: '?', '=' or ''. Will be used as such so '=1' is valid as well.
format	Format string for variadic arguments to be added to AT command; No separator needed. Use d for integer, s for string and b for byte string (requires 2 arguments: string and length)

Returns: last error that happened when parsing AT responses

◆ write_int()

void write_int ( int32_t param )

Writes integer type AT command subparameter.

Starts with the delimiter if not the first param after cmd_start. In case of failure when writing, the last error is set to NSAPI_ERROR_DEVICE_ERROR.

Parameters

param int to be written to modem as AT command subparameter

◆ write_string()

void write_string	(	const char *	param,
		bool	useQuotations = `true`
	)

Writes string type AT command subparamater.

Quotes are added to surround the given string. Starts with the delimiter if not the first param after cmd_start. In case of failure when writing, the last error is set to NSAPI_ERROR_DEVICE_ERROR.

Parameters

param	string to be written to modem as AT command subparameter
useQuotations	flag indicating whether the string should be included in quotation marks

◆ cmd_stop()

void cmd_stop ( )

Stops the AT command by writing command-line terminator CR to mark command as finished.

◆ cmd_stop_read_resp()

void cmd_stop_read_resp ( )

Stops the AT command by writing command-line terminator CR to mark command as finished and reads the OK/ERROR response.

◆ write_bytes()

size_t write_bytes	(	const uint8_t *	data,
		size_t	len
	)

Write bytes without any subparameter delimiters, such as comma.

In case of failure when writing, the last error is set to NSAPI_ERROR_DEVICE_ERROR.

Parameters

data	bytes to be written to modem
len	length of data string

Returns: number of characters successfully written

◆ set_stop_tag()

void set_stop_tag ( const char * stop_tag_seq )

Sets the stop tag for the current scope (response/information response/element) Parameter's reading routines will stop the reading when such tag is found and will set the found flag.

Consume routines will read everything until such tag is found.

Parameters

stop_tag_seq string to be set as stop tag

◆ set_delimiter()

void set_delimiter ( char delimiter )

Sets the delimiter between parameters or between elements of the information response.

Parameter's reading routines will stop when such char is read.

Parameters

delimiter char to be set as _delimiter

◆ set_default_delimiter()

void set_default_delimiter ( )

Sets the delimiter to default value defined by DEFAULT_DELIMITER.

◆ use_delimiter()

void use_delimiter ( bool use_delimiter )

Defines behaviour for using or ignoring the delimiter within an AT command.

Parameters

use_delimiter indicating if delimiter should be used or not

◆ skip_param() [1/2]

void skip_param ( uint32_t count = 1 )

Consumes the reading buffer up to the delimiter or stop_tag.

Parameters

count number of parameters to be skipped

◆ skip_param() [2/2]

void skip_param	(	ssize_t	len,
		uint32_t	count
	)

Consumes the given length from the reading buffer.

Parameters

len	length to be consumed from reading buffer
count	number of parameters to be skipped

◆ skip_param_bytes()

void skip_param_bytes	(	ssize_t	len,
		uint32_t	count
	)

Consumes the given length from the reading buffer even if the stop tag has been found.

Parameters

len	length to be consumed from reading buffer
count	number of parameters to be skipped

◆ read_bytes()

ssize_t read_bytes	(	uint8_t *	buf,
		size_t	len
	)

Reads given number of bytes from receiving buffer without checking any subparameter delimiters, such as comma.

Parameters

buf	output buffer for the read
len	maximum number of bytes to read

Returns: number of successfully read bytes or -1 in case of error

◆ read_string()

ssize_t read_string	(	char *	str,
		size_t	size,
		bool	read_even_stop_tag = `false`
	)

Reads chars from reading buffer.

Terminates with null. Skips the quotation marks. Stops on delimiter or stop tag.

Parameters

str	output buffer for the read
size	maximum number of chars to output including NULL
read_even_stop_tag	if true then try to read even if the stop tag was found previously

Returns: length of output string or -1 in case of read timeout before delimiter or stop tag is found

◆ read_hex_string()

ssize_t read_hex_string	(	char *	str,
		size_t	size
	)

Reads chars representing hex ascii values and converts them to the corresponding chars.

For example: "4156" to "AV". Terminates with null. Skips the quotation marks. Stops on delimiter or stop tag.

Parameters

str	output buffer for the read
size	maximum number of chars to output

Returns: length of output string or -1 in case of read timeout before delimiter or stop tag is found

◆ write_hex_string()

void write_hex_string	(	const char *	str,
		size_t	size,
		bool	quote_string = `true`
	)

Converts contained chars to their hex ascii value and writes the resulting string to the file handle For example: "AV" to "4156".

Parameters

str	input buffer to be converted to hex ascii
size	of the input param str
quote_string	if true it will add the double-quote character at beginning and end of string

◆ read_int()

int32_t read_int ( )

Reads as string and converts result to integer.

Supports only non-negative integers.

Returns: the non-negative integer or -1 in case of error.

◆ resp_start()

void resp_start	(	const char *	prefix = `NULL`,
		bool	stop = `false`
	)

This looks for necessary matches: prefix, OK, ERROR, URCs and sets the correct scope.

Parameters

prefix	string to be matched from receiving buffer. If not NULL and match succeeds, then scope will be set as information response(info_type)
stop	flag to indicate if we go to information response scope or not. (needed when nothing is expected to be received anymore after the prefix match: sms case: "> ", bc95 reboot case)

◆ resp_stop()

void resp_stop ( )

Ends all scopes starting from current scope.

Consumes everything until the scope's stop tag is found, then goes to next scope until response scope is ending. URC match is checked during response scope ending, for every new line / CRLF.

Possible sequence: element scope -> information response scope -> response scope

◆ info_resp()

bool info_resp ( )

Looks for matching the prefix given to resp_start() call.

If needed, it ends the scope of a previous information response. Sets the information response scope if new prefix is found and response scope if prefix is not found.

Returns: true if prefix defined for information response is not empty string and is found, false otherwise.

◆ info_elem()

bool info_elem ( char start_tag )

Looks for matching the start tag.

If needed, it ends the scope of a previous element. Sets the element scope if start tag is found and information response scope if start tag is not found.

Parameters

start_tag tag to be matched to begin parsing an element of an information response

Returns: true if new element is found, false otherwise

◆ consume_to_stop_tag()

bool consume_to_stop_tag ( )

Consumes the received content until current stop tag is found.

Returns: true if stop tag is found, false otherwise

◆ consume_to_stop_tag_even_found()

bool consume_to_stop_tag_even_found ( )

Consumes the received content until current stop tag is found even if stop tag has been found previously.

Returns: true if stop tag is found, false otherwise

◆ get_3gpp_error()

int get_3gpp_error ( )

Return the last 3GPP error code.

Returns: last 3GPP error code

◆ set_debug()

void set_debug ( bool debug_on )

AT debugging, when enabled will print all data read and written, non-printable chars are printed as "[%d]".

AT debug can be enabled at compile time using MBED_CONF_CELLULAR_DEBUG_AT flag or at runtime calling set_debug(). Note that MBED_CONF_MBED_TRACE_ENABLE must also be enabled.

Parameters

debug_on Enable/disable debugging

◆ get_debug()

bool get_debug ( ) const

Get degug state set by set_debug.

Returns: current state of debug

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ATHandler() [1/2]

◆ ATHandler() [2/2]

Member Function Documentation

◆ get_file_handle()

◆ lock()

◆ unlock()

◆ unlock_return_error()

◆ set_urc_handler()

◆ get_last_error()

◆ get_last_device_error()

◆ set_at_timeout() [1/2]

◆ set_at_timeout() [2/2]

◆ restore_at_timeout()

◆ clear_error()

◆ flush()

◆ process_oob()

◆ set_is_filehandle_usable()

◆ sync() [1/2]

◆ sync() [2/2]

◆ set_send_delay()

◆ set_baud()

◆ cmd_start()

◆ cmd_start_stop()

◆ at_cmd_str()

◆ at_cmd_int()

◆ at_cmd_discard()

◆ write_int()

◆ write_string()

◆ cmd_stop()

◆ cmd_stop_read_resp()

◆ write_bytes()

◆ set_stop_tag()

◆ set_delimiter()

◆ set_default_delimiter()

◆ use_delimiter()

◆ skip_param() [1/2]

◆ skip_param() [2/2]

◆ skip_param_bytes()

◆ read_bytes()

◆ read_string()

◆ read_hex_string()

◆ write_hex_string()

◆ read_int()

◆ resp_start()

◆ resp_stop()

◆ info_resp()

◆ info_elem()

◆ consume_to_stop_tag()

◆ consume_to_stop_tag_even_found()

◆ get_3gpp_error()

◆ set_debug()

◆ get_debug()