#include <SerialTxRx.h>

Public Member Functions
	SerialTxRx (void)

	~SerialTxRx (void)

void	openPort (string portName)

void	setPortParams (int baudRate, int timeout=1)

void	getPortParams (int &baudRate, int &timeout, bool &rawMode)

int	readOSPmsg (int patience=MAXBUFFERSIZE *2)

int	readNMEAmsg (int patience=MAXBUFFERSIZE)

void	writeOSPcmd (int mid, string cmdArgs, int base=16)

void	writeNMEAcmd (int mid, string cmdArgs)

void	closePort ()

void	sleepTime (int ms)

Public Attributes
unsigned char	paylenBuff [2]
	a 2 bytes buffer for the payload length bytes

unsigned char	payBuff [MAXBUFFERSIZE]
	message payload data buffer of MAXBUFFERSIZE bytes

unsigned int	payloadLen
	the current payload length, for convenience

Detailed Description

SerialTxRx class defines a data and method to manage the serial comm port where a receiver is connected, and allows sending and receiving messages through it. A program using SerialTxRx would perform the following steps after declaring an object of this class:

To open the serial port with the name given
To set or get the port parameters (baud rate, size, parity)
To read or write OSP or NMEA messages
To skip input bytes / chars until appears the start of an OSP or NMEA message
To close the port

Constructor & Destructor Documentation

SerialTxRx::SerialTxRx ( void )

Constructs an empty SerialTxRx object, without setting comms port parameters.

SerialTxRx::~SerialTxRx ( void )

Destructs SerialTxRx objects.

Member Function Documentation

void SerialTxRx::closePort ( )

closePort closes the currently open serial port.

void SerialTxRx::getPortParams	(	int &	baudRate,
		int &	timeout,
		bool &	rawMode
	)

getPortParams gets current port parameters: baud rate, byte size and parity.

Parameters

baudRate	a variable to place the value of the baud rate
timeout	a variable to place the value of the timeout limit when reading input
mode	a variable to place a true value if raw mode (non canonical) is used, or false otherwise

Exceptions

error string with the message explaining it

void SerialTxRx::openPort ( string portName )

openPort opens the serial port portName to allow reception of messages or sending commands to a SiRF receiver.

Parameters

portName the name of the port to be opened

Exceptions

error message when the port cannot be open, explaining the reason

int SerialTxRx::readNMEAmsg ( int patience = MAXBUFFERSIZE )

readNMEAmsg reads a NMEA message from the serial port.

Parameters

patience the maximum number of skipped chars or unsuccessful reads before returning

Returns

the exit status according to the following values and meaning:

(0) when a correct message has been received;
(1) if the received message has incorrect checksum;
(2) if message received has less than five chars. Minimum NMEA message is $XXX*SS
(3) if the input stream does not contains NMEA messages or an input error occurred or EOF
(4) if NMEA start bytes have not been received before "exhaust patience"

int SerialTxRx::readOSPmsg ( int patience = MAXBUFFERSIZE*2 )

readOSPmsg reads a OSP message from the serial port.

Parameters

patience is the maximum number of bytes to skip or unsuccessful reads from the serial port before returning error

Returns

the exit status according to the following values and meaning:

(0) when a correct formatted OSP message has been received;
(1) if the message has incorrect checksum;
(2) if error occurred when reading payload or not enought bytes were received
(3) if the payload length read is out of margin (>MAXBUFFERSIZE)
(4) if unable to read the two bytes of the OSP payload length
(5) if read error occurred reading OSP payload bytes
(6) if OSP start bytes have not been received before "exhaust patience"

void SerialTxRx::setPortParams	(	int	baudRate,
		int	timeout = `1`
	)

setPortParams sets port baud rate. Other relevant port parameters are set to the following values:

ByteSize = 8
StopBits = ONESTOPBIT;
Parity = NOPARITY;
fBinary = TRUE;
fDtrControl = DTR_CONTROL_DISABLE;
fRtsControl = RTS_CONTROL_DISABLE;

Parameters

baudRate	the value of the baud rate to be set
timeout	the limit for a timer in tenths of a second to wait for input data

Exceptions

error string with the message explaining it

void SerialTxRx::sleepTime ( int ms )

sleepTime stops the process for the milliseconds stated Here it is implemented a version for Windows

void SerialTxRx::writeNMEAcmd	(	int	mid,
		string	cmdArgs
	)

writeNMEAcmd builds a NMEA message command and sends it to receiver through to the serial port.

Parameters

mid	the identification of the command to be generated in the form $PSRF<mid>, ...
cmdArgs	the message parameters: a comma separated list of arguments

Exceptions

error string message explaining it

void SerialTxRx::writeOSPcmd	(	int	mid,
		string	cmdArgs,
		int	base = `16`
	)

writeOSPcmd builds a OSP message command and sends it to receiver through the serial port.

Parameters

mid	the message identification of the OSP command to be generated
cmdArgs	the rest of message payload, as a whitespace-separated sequence of bytes
base	the base used to write the parameters (16, 10, ...)

Exceptions

error string when message cannot be send

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

SerialTxRx/src_Windows/SerialTxRx.h
SerialTxRx/src_Windows/SerialTxRx.cpp

Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation