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/**
* @example serial_port_read_write.cpp
*/
#include <libserial/SerialPort.h>
#include <cstdlib>
#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.
*/
int main()
{
using namespace LibSerial ;
// Instantiate two SerialPort objects.
SerialPort serial_port_1 ;
SerialPort serial_port_2 ;
try
{
// Open the Serial Ports at the desired hardware devices.
serial_port_1.Open(SERIAL_PORT_1) ;
serial_port_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_port_1.SetBaudRate(BaudRate::BAUD_115200) ;
serial_port_2.SetBaudRate(BaudRate::BAUD_115200) ;
// Set the number of data bits.
serial_port_1.SetCharacterSize(CharacterSize::CHAR_SIZE_8) ;
serial_port_2.SetCharacterSize(CharacterSize::CHAR_SIZE_8) ;
// Set the hardware flow control.
serial_port_1.SetFlowControl(FlowControl::FLOW_CONTROL_NONE) ;
serial_port_2.SetFlowControl(FlowControl::FLOW_CONTROL_NONE) ;
// Set the parity.
serial_port_1.SetParity(Parity::PARITY_NONE) ;
serial_port_2.SetParity(Parity::PARITY_NONE) ;
// Set the number of stop bits.
serial_port_1.SetStopBits(StopBits::STOP_BITS_1) ;
serial_port_2.SetStopBits(StopBits::STOP_BITS_1) ;
// Setup variables to store outgoing and incoming data.
char write_byte_1 = 'a' ;
char write_byte_2 = 'b' ;
char read_byte_1 = ' ' ;
char read_byte_2 = ' ' ;
// 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 WriteByte() and ReadByte() for one byte of data:"
<< std::endl ;
// Write a single byte of data to the serial ports.
serial_port_1.WriteByte(write_byte_1) ;
serial_port_2.WriteByte(write_byte_2) ;
// Wait until the data has actually been transmitted.
serial_port_1.DrainWriteBuffer() ;
serial_port_2.DrainWriteBuffer() ;
// Specify a timeout value (in milliseconds).
size_t timeout_milliseconds = 25 ;
try
{
// Read a single byte of data from the serial ports.
serial_port_1.ReadByte(read_byte_1, timeout_milliseconds) ;
serial_port_2.ReadByte(read_byte_2, timeout_milliseconds) ;
}
catch (const ReadTimeout&)
{
std::cerr << "The ReadByte() call has timed out." << std::endl ;
}
// Print to the terminal what was sent and what was received.
std::cout << "\tSerial Port 1 sent:\t" << write_byte_1 << std::endl
<< "\tSerial Port 2 received:\t" << read_byte_2 << std::endl
<< std::endl ;
std::cout << "\tSerial Port 2 sent:\t" << write_byte_2 << std::endl
<< "\tSerial Port 1 received:\t" << read_byte_1 << std::endl
<< std::endl ;
// Print to the terminal what will take place next.
std::cout << "Using Write() and Read() for a specified number of "
<< "bytes of data:" << std::endl ;
// Write a string to each serial port.
serial_port_1.Write(write_string_1) ;
serial_port_2.Write(write_string_2) ;
// Wait until the data has actually been transmitted.
serial_port_1.DrainWriteBuffer() ;
serial_port_2.DrainWriteBuffer() ;
try
{
// Read the appropriate number of bytes from each serial port.
serial_port_1.Read(read_string_1, write_string_2.size(), timeout_milliseconds) ;
serial_port_2.Read(read_string_2, write_string_1.size(), timeout_milliseconds) ;
}
catch (const ReadTimeout&)
{
std::cerr << "The Read() call has timed out." << std::endl ;
}
// 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() ;
// Print to the terminal what will take place next.
std::cout << "Using Write() and ReadLine() to write a string and "
<< "read a line of data:" << std::endl << std::endl ;
// Prompt the user for input.
std::cout << R"(Enter something you would like to send over )"
<< R"(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 ;
}
// Write the user input to the serial port.
serial_port_1.Write(user_input + "\n") ;
// Read the data transmitted from the corresponding serial port.
serial_port_2.ReadLine(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_port_1.Close() ;
serial_port_2.Close() ;
// Successful program completion.
std::cout << "The example program successfully completed!" << std::endl ;
return EXIT_SUCCESS ;
}
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