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/**
* @example serial_stream_read_write.cpp
*/
#include <libserial/SerialStream.h>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <iostream>
#include <unistd.h>
constexpr const char* const SERIAL_PORT_1 = "/dev/ttyUSB0" ;
constexpr const char* const SERIAL_PORT_2 = "/dev/ttyUSB1" ;
/**
* @brief This example demonstrates multiple methods to read and write
* serial stream data utilizing std::iostream functionality.
*/
int main()
{
using namespace LibSerial ;
// Instantiate two SerialStream objects.
SerialStream serial_stream_1 ;
SerialStream serial_stream_2 ;
try
{
// Open the Serial Ports at the desired hardware devices.
serial_stream_1.Open(SERIAL_PORT_1) ;
serial_stream_2.Open(SERIAL_PORT_2) ;
}
catch (const OpenFailed&)
{
std::cerr << "The serial ports did not open correctly." << std::endl ;
return EXIT_FAILURE ;
}
// Set the baud rates.
serial_stream_1.SetBaudRate(BaudRate::BAUD_115200) ;
serial_stream_2.SetBaudRate(BaudRate::BAUD_115200) ;
// Set the number of data bits.
serial_stream_1.SetCharacterSize(CharacterSize::CHAR_SIZE_8) ;
serial_stream_2.SetCharacterSize(CharacterSize::CHAR_SIZE_8) ;
// Turn off hardware flow control.
serial_stream_1.SetFlowControl(FlowControl::FLOW_CONTROL_NONE) ;
serial_stream_2.SetFlowControl(FlowControl::FLOW_CONTROL_NONE) ;
// Disable parity.
serial_stream_1.SetParity(Parity::PARITY_NONE) ;
serial_stream_2.SetParity(Parity::PARITY_NONE) ;
// Set the number of stop bits.
serial_stream_1.SetStopBits(StopBits::STOP_BITS_1) ;
serial_stream_2.SetStopBits(StopBits::STOP_BITS_1) ;
// Variables to store outgoing and incoming data.
std::string write_string_1 = "\"Do what you can, with what you have, where you are.\" - Theodore Roosevelt" ;
std::string write_string_2 = "\"Simplicity is prerequisite for reliability.\" - Edsger W. Dijkstra" ;
std::string read_string_1 = "" ;
std::string read_string_2 = "" ;
// Print to the terminal what will take place next.
std::cout << "\nUsing write() and read() for a specified number of "
<< "bytes of data:" << std::endl ;
// Write a specified number of bytes of data.
serial_stream_1.write(write_string_1.c_str(), write_string_1.size()) ;
serial_stream_2.write(write_string_2.c_str(), write_string_2.size()) ;
// Wait until the data has actually been transmitted.
serial_stream_1.DrainWriteBuffer() ;
serial_stream_2.DrainWriteBuffer() ;
// Char arrays to store incoming data.
char* read_array_1 = new char[write_string_2.size()] ;
char* read_array_2 = new char[write_string_1.size()] ;
// Use inheritted std::istream read() method to read the data.
serial_stream_1.read(read_array_1, write_string_2.size()) ;
serial_stream_2.read(read_array_2, write_string_1.size()) ;
// Print to the terminal what was sent and what was received.
std::cout << "\tSerial Port 1 sent:\t" << write_string_1 << std::endl
<< "\tSerial Port 2 received:\t" << read_array_2 << std::endl
<< std::endl ;
std::cout << "\tSerial Port 2 sent:\t" << write_string_2 << std::endl
<< "\tSerial Port 1 received:\t" << read_array_1 << std::endl
<< std::endl ;
// Print to the terminal what will take place next.
std::cout << "Using the \"<<\" operator and getline() for a line of data:"
<< std::endl ;
// Write a line at each serial port.
serial_stream_1 << write_string_1 << std::endl ;
serial_stream_2 << write_string_2 << std::endl ;
// Wait until the data has actually been transmitted.
serial_stream_1.DrainWriteBuffer() ;
serial_stream_2.DrainWriteBuffer() ;
// Read a line at each serial port.
std::getline(serial_stream_1, read_string_1) ;
std::getline(serial_stream_2, read_string_2) ;
// Print to the terminal what was sent and what was received.
std::cout << "\tSerial Port 1 sent:\t" << write_string_1 << std::endl
<< "\tSerial Port 2 received:\t" << read_string_2 << std::endl
<< std::endl ;
std::cout << "\tSerial Port 2 sent:\t" << write_string_2 << std::endl
<< "\tSerial Port 1 received:\t" << read_string_1 << std::endl
<< std::endl ;
// Variable to hold user input.
std::string user_input ;
user_input.clear() ;
// Prompt the user for input.
std::cout << "Type something you would like to send over serial,"
<< " (enter \"Q\" or \"q\" to quit): " << std::flush ;
while(true)
{
// Get input from the user.
std::getline(std::cin, user_input) ;
if (user_input == "q" ||
user_input == "Q" ||
user_input == "")
{
break ;
}
// Print to the terminal what will take place next.
std::cout << "Using the \"<<\" and \">>\" operators to send "
<< "and receive your data: " << std::endl ;
// Write the user input to the serial port.
serial_stream_1 << user_input << std::endl ;
// Read the data transmitted from the corresponding serial port.
// Note: The ">>" operator behavior is tricky if whitespace or
// nothing is entered by the user!
serial_stream_2 >> read_string_2 ;
// Print to the terminal what was sent and what was received.
std::cout << "\tSerial Port 1 sent:\t" << user_input << std::endl
<< "\tSerial Port 2 received:\t" << read_string_2 << std::endl ;
}
// Close the serial ports and end the program.
serial_stream_1.Close() ;
serial_stream_2.Close() ;
// Successful program completion.
std::cout << "The example program successfully completed!" << std::endl ;
return EXIT_SUCCESS ;
}
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