NMEA Class Reference

#include <NMEA.h>

Inheritance diagram for NMEA:

List of all members.

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Detailed Description

NMEA abstract base class for representing NMEA 0183 message strings.

Public Types
enum	MESSAGE_TYPES {   t_GPGGA = 0, t_GPRMC, t_GPGLL, t_GPGSV,   t_GPGSA, t_GPMSS, t_GPVTG, tGPZDA,   t_UNKNOWN }
	NMEA sentence type enum (one for each sentence). More...
enum	FIELDS {   FIELD_0 = 0, FIELD_1, FIELD_2, FIELD_3,   FIELD_4, FIELD_5, FIELD_6, FIELD_7,   FIELD_8, FIELD_9, FIELD_10, FIELD_11,   FIELD_12, FIELD_13, FIELD_14, FIELD_15,   FIELD_16, FIELD_17, FIELD_18, FIELD_19,   FIELD_20, FIELD_21, FIELD_22, FIELD_23,   FIELD_24, FIELD_25, FIELD_26, FIELD_27,   FIELD_28, FIELD_29, FIELD_30, FIELD_31 }
	Enumeration of indices used to select NMEA string fields. More...
typedef enum NMEA::MESSAGE_TYPES	MessageType
	NMEA sentence type enum (one for each sentence).
Public Member Functions
	NMEA ()
	Default no argument constructor.
MessageType	getType ()
	Returns: NMEA message type
Field *	getField (NMEA::FIELDS index)
	Returns: specified field
void	setField (NMEA::FIELDS field, int value)
	Set integer field.
void	setField (NMEA::FIELDS field, unsigned int value)
	Set unsigned int field.
void	setField (NMEA::FIELDS field, char *value)
	Set character pointer field.
void	setField (NMEA::FIELDS field, char value)
	set character field
void	setField (NMEA::FIELDS field, unsigned char value)
	Set unsigned character field.
void	setField (NMEA::FIELDS field, double value)
	Set double field.
void	setField (NMEA::FIELDS field, time_t value)
	Set time_t field.
unsigned short int	checksum (const char *nmeaString) const
	Generate checksum of NMEA string Checksum is XOR checksum of all bytes between '$' and '*', exclusive.
Protected Attributes
unsigned int	_nFields
	Number of fields in this NMEA message (differs by subclass).
MessageType	_type
	NMEA sentence (message) type.
Field	_fields [MAX_NMEA_FIELDS]
	Array of Field objects.

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Member Typedef Documentation

typedef enum NMEA::MESSAGE_TYPES NMEA::MessageType

NMEA sentence type enum (one for each sentence).

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Member Enumeration Documentation

enum NMEA::MESSAGE_TYPES

NMEA sentence type enum (one for each sentence).

Message Types

• GGA: Time, position and fix type data.
• GLL: Latitude, longitude, UTC time of position fix and status.
• GSA: GPS receiver operating mode, satellites used in the position solution, and DOP values.
• GSV: The number of GPS satellites in view satellite ID numbers, elevation, azimuth, and SNR values.
• MSS: Signal-to-noise ratio, signal strength, frequency, and bit rate from a radio-beacon receiver.
• RMC: Time, date, position, course and speed data.
• VTG: Course and speed information relative to the ground.
• ZDA: PPS timing message (synchronized to PPS).

Note:

Note:

Currently only GPRMC and GPGGA messages are implemented.

enum NMEA::FIELDS

Enumeration of indices used to select NMEA string fields.

Subclasses create their own enumerations of mnemonics that reference (map onto) these field indices.

See also:

GPGGA::FIELDS, GPRMC::FIELDS

Reimplemented in GPGGA, and GPRMC.

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Member Function Documentation

Field * NMEA::getField

(

NMEA::FIELDS

index

)

Returns:

specified field

Parameters:

index

field index

See also:

NMEA::FIELDS

void NMEA::setField	(	NMEA::FIELDS	field,
		int	value
	)

Set integer field.

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		unsigned int	value
	)

Set unsigned int field.

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		char *	value
	)

Set character pointer field.

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		char	value
	)

set character field

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		unsigned char	value
	)

Set unsigned character field.

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		double	value
	)

Set double field.

Parameters:

	field	field index
	value	new value

void NMEA::setField	(	NMEA::FIELDS	field,
		time_t	value
	)

Set time_t field.

Parameters:

	field	field index
	value	new value

unsigned short int NMEA::checksum

(

const char *

nmeaString

)

const [inline]

Generate checksum of NMEA string Checksum is XOR checksum of all bytes between '$' and '*', exclusive.

Parameters:

nmeaString

NMEA string to compute checksum for

Returns:

checksum value (unsigned short)

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Member Data Documentation

MessageType NMEA::_type [protected]

NMEA sentence (message) type.

See also:

NMEA::MESSAGE_TYPES

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

• camera/NMEA.h
• camera/NMEA.cc

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