#include <AP_GPS_NMEA.h>

Inheritance diagram for AP_GPS_NMEA:

Collaboration diagram for AP_GPS_NMEA:

Public Member Functions
	AP_GPS_NMEA (AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port)

bool	read ()

const char *	name () const override

Public Member Functions inherited from AP_GPS_Backend
	AP_GPS_Backend (AP_GPS &_gps, AP_GPS::GPS_State &_state, AP_HAL::UARTDriver *_port)

virtual	~AP_GPS_Backend (void)

virtual AP_GPS::GPS_Status	highest_supported_status (void)

virtual bool	is_configured (void)

virtual void	inject_data (const uint8_t *data, uint16_t len)

virtual bool	supports_mavlink_gps_rtk_message ()

virtual void	send_mavlink_gps_rtk (mavlink_channel_t chan)

virtual void	broadcast_configuration_failure_reason (void) const

virtual void	handle_msg (const mavlink_message_t *msg)

virtual void	handle_gnss_msg (const AP_GPS::GPS_State &msg)

virtual bool	get_lag (float &lag) const

virtual bool	is_healthy (void) const

void	broadcast_gps_type () const

virtual void	Write_DataFlash_Log_Startup_messages () const

virtual bool	prepare_for_arming (void)

Static Public Member Functions
static bool	_detect (struct NMEA_detect_state &state, uint8_t data)

Private Types
enum	_sentence_types { _GPS_SENTENCE_RMC = 32, _GPS_SENTENCE_GGA = 64, _GPS_SENTENCE_VTG = 96, _GPS_SENTENCE_OTHER = 0 }
	Coding for the GPS sentences that the parser handles. More...

Private Member Functions
bool	_decode (char c)

int16_t	_from_hex (char a)

uint32_t	_parse_degrees ()

bool	_term_complete ()

bool	_have_new_message (void)
	return true if we have a new set of NMEA messages More...

Static Private Member Functions
static int32_t	_parse_decimal_100 (const char *p)

Private Attributes
uint8_t	_parity
	NMEA message checksum accumulator. More...

bool	_is_checksum_term
	current term is the checksum More...

char	_term [15]
	buffer for the current term within the current sentence More...

uint8_t	_sentence_type
	the sentence type currently being processed More...

uint8_t	_term_number
	term index within the current sentence More...

uint8_t	_term_offset
	character offset with the term being received More...

bool	_gps_data_good
	set when the sentence indicates data is good More...

int32_t	_new_time
	time parsed from a term More...

int32_t	_new_date
	date parsed from a term More...

int32_t	_new_latitude
	latitude parsed from a term More...

int32_t	_new_longitude
	longitude parsed from a term More...

int32_t	_new_altitude
	altitude parsed from a term More...

int32_t	_new_speed
	speed parsed from a term More...

int32_t	_new_course
	course parsed from a term More...

uint16_t	_new_hdop
	HDOP parsed from a term. More...

uint8_t	_new_satellite_count
	satellite count parsed from a term More...

uint8_t	_new_quality_indicator
	GPS quality indicator parsed from a term. More...

uint32_t	_last_RMC_ms = 0

uint32_t	_last_GGA_ms = 0

uint32_t	_last_VTG_ms = 0

Static Private Attributes
static const char	_initialisation_blob []

Init strings
In init, an attempt is made to configure the GPS unit to send just the messages that we are interested in using these strings
static const char	_SiRF_init_string []
	init string for SiRF units More...

static const char	_MTK_init_string []
	init string for MediaTek units More...

static const char	_ublox_init_string []
	init string for ublox units More...

Friends
class	AP_GPS_NMEA_Test

Additional Inherited Members
Protected Member Functions inherited from AP_GPS_Backend
int32_t	swap_int32 (int32_t v) const

int16_t	swap_int16 (int16_t v) const

void	fill_3d_velocity (void)

void	make_gps_time (uint32_t bcd_date, uint32_t bcd_milliseconds)

void	_detection_message (char *buffer, uint8_t buflen) const

bool	should_df_log () const

Protected Attributes inherited from AP_GPS_Backend
AP_HAL::UARTDriver *	port
	UART we are attached to. More...

AP_GPS &	gps
	access to frontend (for parameters) More...

AP_GPS::GPS_State &	state
	public state for this instance More...

Detailed Description

NMEA parser

Definition at line 51 of file AP_GPS_NMEA.h.

Member Enumeration Documentation

◆ _sentence_types

enum AP_GPS_NMEA::_sentence_types

private

Coding for the GPS sentences that the parser handles.

Enumerator
_GPS_SENTENCE_RMC
_GPS_SENTENCE_GGA
_GPS_SENTENCE_VTG
_GPS_SENTENCE_OTHER

Definition at line 69 of file AP_GPS_NMEA.h.

Constructor & Destructor Documentation

◆ AP_GPS_NMEA()

AP_GPS_NMEA::AP_GPS_NMEA	(	AP_GPS &	_gps,
		AP_GPS::GPS_State &	_state,
		AP_HAL::UARTDriver *	_port
	)

Definition at line 53 of file AP_GPS_NMEA.cpp.

Member Function Documentation

◆ _decode()

bool AP_GPS_NMEA::_decode ( char c )

private

Update the decode state machine with a new character

Parameters

c	The next character in the NMEA input stream

Returns: True if processing the character has resulted in an update to the GPS state

Definition at line 84 of file AP_GPS_NMEA.cpp.

Referenced by read().

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◆ _detect()

bool AP_GPS_NMEA::_detect	(	struct NMEA_detect_state &	state,
		uint8_t	data
	)

static

Definition at line 421 of file AP_GPS_NMEA.cpp.

Referenced by AP_GPS::detect_instance().

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◆ _from_hex()

int16_t AP_GPS_NMEA::_from_hex ( char a )

private

Return the numeric value of an ascii hex character

Parameters

a	The character to be converted

Returns: The value of the character as a hex digit

Definition at line 125 of file AP_GPS_NMEA.cpp.

Referenced by _term_complete().

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◆ _have_new_message()

bool AP_GPS_NMEA::_have_new_message ( void )

private

return true if we have a new set of NMEA messages

Definition at line 211 of file AP_GPS_NMEA.cpp.

Referenced by _term_complete().

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◆ _parse_decimal_100()

int32_t AP_GPS_NMEA::_parse_decimal_100 ( const char * p )

staticprivate

Parses the as a NMEA-style decimal number with up to 3 decimal digits.

Returns: The value expressed by the string in , multiplied by 100.

Definition at line 135 of file AP_GPS_NMEA.cpp.

Referenced by _term_complete(), and AP_GPS_NMEA_Test::parse_decimal_100().

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◆ _parse_degrees()

uint32_t AP_GPS_NMEA::_parse_degrees ( )

private

Parses the current term as a NMEA-style degrees + minutes value with up to four decimal digits.

This gives a theoretical resolution limit of around 1cm.

Returns: The value expressed by the string in _term, multiplied by 1e7.

Definition at line 166 of file AP_GPS_NMEA.cpp.

Referenced by _term_complete().

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◆ _term_complete()

bool AP_GPS_NMEA::_term_complete ( )

private

Processes the current term when it has been deemed to be complete.

Each GPS message is broken up into terms separated by commas. Each term is then processed by this function as it is received.

Returns: True if completing the term has resulted in an update to the GPS state.

Definition at line 237 of file AP_GPS_NMEA.cpp.

Referenced by _decode().

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◆ name()

const char* AP_GPS_NMEA::name ( ) const

inlineoverridevirtual

Implements AP_GPS_Backend.

Definition at line 65 of file AP_GPS_NMEA.h.

◆ read()

bool AP_GPS_NMEA::read ( void )

virtual

Checks the serial receive buffer for characters, attempts to parse NMEA data and updates internal state accordingly.

Implements AP_GPS_Backend.

Definition at line 60 of file AP_GPS_NMEA.cpp.

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Friends And Related Function Documentation

◆ AP_GPS_NMEA_Test

friend class AP_GPS_NMEA_Test

friend

Definition at line 53 of file AP_GPS_NMEA.h.

Member Data Documentation

◆ _gps_data_good

bool AP_GPS_NMEA::_gps_data_good

private

set when the sentence indicates data is good

Definition at line 128 of file AP_GPS_NMEA.h.

Referenced by _decode(), and _term_complete().

◆ _initialisation_blob

const char AP_GPS_NMEA::_initialisation_blob[]

staticprivate

Definition at line 158 of file AP_GPS_NMEA.h.

◆ _is_checksum_term

bool AP_GPS_NMEA::_is_checksum_term

private

current term is the checksum

Definition at line 123 of file AP_GPS_NMEA.h.

Referenced by _decode(), and _term_complete().

◆ _last_GGA_ms

uint32_t AP_GPS_NMEA::_last_GGA_ms = 0

private

Definition at line 145 of file AP_GPS_NMEA.h.

Referenced by _have_new_message(), and _term_complete().

◆ _last_RMC_ms

uint32_t AP_GPS_NMEA::_last_RMC_ms = 0

private

Definition at line 144 of file AP_GPS_NMEA.h.

Referenced by _have_new_message(), and _term_complete().

◆ _last_VTG_ms

uint32_t AP_GPS_NMEA::_last_VTG_ms = 0

private

Definition at line 146 of file AP_GPS_NMEA.h.

Referenced by _have_new_message(), and _term_complete().

◆ _MTK_init_string

const char AP_GPS_NMEA::_MTK_init_string[]

staticprivate

init string for MediaTek units

Definition at line 154 of file AP_GPS_NMEA.h.

◆ _new_altitude

int32_t AP_GPS_NMEA::_new_altitude

private

altitude parsed from a term

Definition at line 137 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_course

int32_t AP_GPS_NMEA::_new_course

private

course parsed from a term

Definition at line 139 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_date

int32_t AP_GPS_NMEA::_new_date

private

date parsed from a term

Definition at line 134 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_hdop

uint16_t AP_GPS_NMEA::_new_hdop

private

HDOP parsed from a term.

Definition at line 140 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_latitude

int32_t AP_GPS_NMEA::_new_latitude

private

latitude parsed from a term

Definition at line 135 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_longitude

int32_t AP_GPS_NMEA::_new_longitude

private

longitude parsed from a term

Definition at line 136 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_quality_indicator

uint8_t AP_GPS_NMEA::_new_quality_indicator

private

GPS quality indicator parsed from a term.

Definition at line 142 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_satellite_count

uint8_t AP_GPS_NMEA::_new_satellite_count

private

satellite count parsed from a term

Definition at line 141 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_speed

int32_t AP_GPS_NMEA::_new_speed

private

speed parsed from a term

Definition at line 138 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _new_time

int32_t AP_GPS_NMEA::_new_time

private

time parsed from a term

Definition at line 133 of file AP_GPS_NMEA.h.

Referenced by _term_complete().

◆ _parity

uint8_t AP_GPS_NMEA::_parity

private

NMEA message checksum accumulator.

Definition at line 122 of file AP_GPS_NMEA.h.

Referenced by _decode(), and _term_complete().

◆ _sentence_type

uint8_t AP_GPS_NMEA::_sentence_type

private

the sentence type currently being processed

Definition at line 125 of file AP_GPS_NMEA.h.

Referenced by _decode(), and _term_complete().

◆ _SiRF_init_string

const char AP_GPS_NMEA::_SiRF_init_string[]

staticprivate

init string for SiRF units

Definition at line 153 of file AP_GPS_NMEA.h.

◆ _term

char AP_GPS_NMEA::_term[15]

private

buffer for the current term within the current sentence

Definition at line 124 of file AP_GPS_NMEA.h.

Referenced by _decode(), _parse_degrees(), _term_complete(), and AP_GPS_NMEA().

◆ _term_number

uint8_t AP_GPS_NMEA::_term_number

private

term index within the current sentence

Definition at line 126 of file AP_GPS_NMEA.h.

Referenced by _decode(), and _term_complete().

◆ _term_offset

uint8_t AP_GPS_NMEA::_term_offset

private

character offset with the term being received

Definition at line 127 of file AP_GPS_NMEA.h.

Referenced by _decode().

◆ _ublox_init_string

const char AP_GPS_NMEA::_ublox_init_string[]

staticprivate

init string for ublox units

Definition at line 155 of file AP_GPS_NMEA.h.

The documentation for this class was generated from the following files:

libraries/AP_GPS/AP_GPS_NMEA.h
libraries/AP_GPS/AP_GPS_NMEA.cpp

Public Member Functions

Static Public Member Functions

Private Types

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ _sentence_types

Constructor & Destructor Documentation

◆ AP_GPS_NMEA()

Member Function Documentation

◆ _decode()

◆ _detect()

◆ _from_hex()

◆ _have_new_message()

◆ _parse_decimal_100()

◆ _parse_degrees()

◆ _term_complete()

◆ name()

◆ read()

Friends And Related Function Documentation

◆ AP_GPS_NMEA_Test

Member Data Documentation

◆ _gps_data_good

◆ _initialisation_blob

◆ _is_checksum_term

◆ _last_GGA_ms

◆ _last_RMC_ms

◆ _last_VTG_ms

◆ _MTK_init_string

◆ _new_altitude

◆ _new_course

◆ _new_date

◆ _new_hdop

◆ _new_latitude

◆ _new_longitude

◆ _new_quality_indicator

◆ _new_satellite_count

◆ _new_speed

◆ _new_time

◆ _parity

◆ _sentence_type

◆ _SiRF_init_string

◆ _term

◆ _term_number

◆ _term_offset

◆ _ublox_init_string