int chksum = 0;

for (unsigned int i = 0; i <= (msg.length()-1); i++) {

chksum ^= (int)msg[i];

}

return chksum;

// Initialize read buffer, and serial port parameters

int fd;

const int baud = 9600;

char serialport[] = "/dev/ttyACM0";

// Define the delimiters of message

std::string startChar = "$";

std::string endChar = "!";

std::size_t foundStart, foundEnd;

int chksum = 0;

// Setup file name for log file

time_t rawtime;

struct tm *timeinfo;

time(&rawtime);

timeinfo = localtime(&rawtime);

std::string timestr (asctime(timeinfo));

std::string logPath = "/home/edward/Documents/DataLogging/log_files/";

std::string filename = logPath + "log_" + timestr.substr(0,timestr.length()-1) + ".dat";

// Display file name

cout << "main: Data is being logged into the file: ";

cout << filename << endl;

// Initialize serial port

Serial serial;

fd = serial.Initialize(serialport, baud);

// Read from serial port and write to file

if (fd > 0) {

std::ofstream file (filename.c_str());

if (file.is_open()) {

cout << "main: File opened successfully, logging data...\n";

while (1) {

char buf[127];

if (serial.ReadBlock(fd, buf) != -1) {

//file << buf;

cout << buf;

//printf("%s", buf);

//cout << sizeof(buf) << endl;

// Convert character array into string

std::string buffer = buf;

//cout << buffer;

foundStart = buffer.find_first_of(startChar);

foundEnd = buffer.find_first_of(endChar, foundStart+1);

//cout << foundStart << "|" << foundEnd << endl;

if ((foundStart != std::string::npos) && (foundEnd != std::string::npos)) {

std::string msg = buffer.substr(foundStart, (foundEnd-foundStart+1));

std::string::size_type sz;

int msgChksum = std::stoi(buffer.substr((foundEnd+1), (buffer.length()-foundEnd-2)), &sz);

chksum = findChksum(msg);

if (chksum == msgChksum) {

msg = msg + '\n';

//file << msg;

//cout << msg;

}

}

}

}

}

else {

cout << "main: File failed to open, exiting...\n";

exit(EXIT_FAILURE);

}

}

else {

cout << "main: Initialization failed, exiting...\n";

exit(EXIT_FAILURE);

}

return 0;

}