int cClassSerialLIB::ReadPort(/*QChar * Response*/)
{
long int iIn;
counter_uart2 =0;
for (int i=0;i<6000;i++)
array_uart2[i]='\0';
if (fd < 1)
{
printf(" port is not open\n");
return -1;
}
iIn = read(fd, array_uart2, sizeof(array_uart2));
static int count=0;
if (iIn < 0)
{
if (errno == EAGAIN)
{
//qDebug("Read nothing");
return 0; // assume that command generated no response
}
else
{
printf("read error %d %s\n", errno, strerror(errno));
}
}
counter_uart2=iIn;
return iIn;
}
and open function:
Code:
bool cClassSerialLIB::OpenPort(bool bloccante)
{
// make sure port is closed
ClosePort();
//ttymxc4
QByteArray Porta_byte_array = Porta.toLatin1();
const char* Porta_char=Porta_byte_array.data();
fd = open(Porta_char/*"/dev/ttymxc4"*/, O_RDWR |
O_NOCTTY | /* tells UNIX that this program doesn't want to be the "controlling terminal" for that port*/
O_NDELAY); /* tells UNIX that this program doesn't care what state the DCD signal line is in */
if (fd < 0)
{
qDebug("errore in apertura %d %s\n", errno, strerror(errno));
return false;
}
else
{
qDebug("ok %d",fd);
struct termios options;
/* The FNDELAY option causes the read function to return 0 if no
characters are available on the port. To restore normal (blocking) behavior,
call fcntl() without the FNDELAY option: */
if(bloccante)
{
printf("bloccante\n");
fcntl(fd, F_SETFL, 0);
}
else
{
printf("NON bloccante");
fcntl(fd, F_SETFL, FNDELAY);
}
//cfmakeraw(&options); //ABILITARLO NEL CASO DI ERRORE!
tcgetattr(fd, &options);
//set port speed 115200
cfsetispeed(&options, B115200);
cfsetospeed(&options, B115200);
options.c_cflag |= (CLOCAL | CREAD);
//set 8n1
options.c_cflag &= ~PARENB; /* Enable parity bit */
options.c_cflag &= ~CSTOPB; /* 2 stop bits (1 otherwise) */
options.c_cflag &= ~CSIZE; /* Mask the character size bits */
options.c_cflag |= CS8; /* Select 8 data bits */
options.c_iflag &= ~IXON; //RIMUOVE X0N/XOFF control
options.c_iflag &= ~IXOFF;
options.c_iflag &= ~IGNCR;
//set raw input
options.c_lflag &= ~(ICANON | /*Enable canonical input (else raw)*/
ECHO | /*Enable echoing of input characters*/
ECHOE | /*Echo erase character as BS-SP-BS*/
ISIG); /*Enable SIGINTR, SIGSUSP, SIGDSUSP, and SIGQUIT signals*/
tcsetattr(fd, TCSANOW, &options); /*Make changes now without waiting for data to complete*/
}
return true;
}
Also, the read() library call returns "ssize_t", not "long int". They might coincidentally be the same on your system's architecture, but they are not the same by definition. You then truncate the "long int" value by returning an "int" from your readPort() method.
Also, you are not checking the return values for your calls to fcntl(), tcgetattr(), cfsetispeed(), cfsetospeed(), or tcsetattr(). How do you know if those calls succeeded?
Also, the read() library call returns "ssize_t", not "long int". They might coincidentally be the same on your system's architecture, but they are not the same by definition. You then truncate the "long int" value by returning an "int" from your readPort() method.
Also, you are not checking the return values for your calls to fcntl(), tcgetattr(), cfsetispeed(), cfsetospeed(), or tcsetattr(). How do you know if those calls succeeded?
how checking the return values for my calls? thanks?
I've modified my Read Function:
Code:
int cClassSerialLIB::ReadPort_poll(){
int iIn;
struct pollfd pfds[5];
pfds[0].fd = fd;
pfds[0].events = POLLIN;
int nfds = 1;
while(1){
/* poll aspetta indefinitivamente (-1) */
int pollret = poll(pfds, nfds, -1);
if (pollret == -1) {
//perror("poll");
continue;
}
/* 2) timeout: this should never happen really... */
if (pollret == 0) {
continue;
}
if(pfds[0].revents == POLLIN){
iIn = read(fd, array_uart2, sizeof(array_uart2));
if (iIn < 0)
{
if (errno == EAGAIN)
{
continue; // assume that command generated no response
}
else
{
printf("read error %d %s\n", errno, strerror(errno));
} // end if
}
aggiorna1();
}
}
}
aggiorna() is decodified function of my packets data, infact i receive a packet data(310 byte at max) every 50ms and so (115200 8n1) i have 1byte every 87us and so 27 ms for trasmission!
With this function i have error in my arrayuart2(the work's buffer) infact i have error on byte for example len payload is wrongor other similar errors:
My protocol:
M A M <-- header first 3 bytes
len payload <-- 2 byte
payload <--1--300 byte
EOM='m' <--1 byte
checksum<--1 byte
If i write
if(pfds[0].revents == POLLIN){
sleep(1);
iIn = read(fd, array_uart2, sizeof(array_uart2));
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