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:
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));
It work without errors but i think that i lose some packets of data because i receive data every 50ms and i wait 1second...
Hello,
I have an unloaded T5140 machine and want to access the ILOM for the first time and subsequently the network port after that., and then load Solaris 10 the final January 2011 build.
The first part is what confuses me -the cabling.
I am coming from a Windows machine (w/appropriate... (5 Replies)
Dear List -
I am trying to capture data from a serial port and write it to a file.
/var/www$ cat /dev/ttyS0 > scale_value.html
cat: /dev/ttyS0: Device or resource busy
/var/www# cat /proc/tty/driver/serial
serinfo:1.0 driver revision:
0: uart:16550A port:000003F8 irq:4 tx:90... (11 Replies)
Hi
I try to communicate with a GSM modem, from C, for sending SMS.
I use standart AT-commands.
Working well with terminal.
There is no problem writing ti the port.
But when I try to read I only get a echo, I write "ATI" and get "ATI" back, I should get somthing like "SIEMENS 35... (4 Replies)
hey frns pls help me out !!
i hav a code of c that i have to include in my project.
i am using a device (geomeda) that has unix based OS. it also support SIM card for connecting to server . I need to send SMS to user from this device..
below code is not working .. i am unable to send sms and the... (7 Replies)
Hi Everyone,
In my environment, I have few T5220. On the iLOM Management Card, I have both Network and Serial port are cabled, I don't have any issues while I try to connect using Network Management port, but when I try to connect the serial port for the same server which is actually connected... (3 Replies)
Hi,
I have a external board connected to my serial port. I need to execute "shutdown -r now" command when system boot up. When system boots up it requires a username ans password. Then I need to run my command. I can use rc script but that is rebooting system before it asks for username and... (0 Replies)
I have problem with C programming. I want to send & receive data through serial communication. I send data(command) to device to get data from device but when receive data, it can't get altogether of data.
It get only some data. What should I do to get altogether of data?
If all of... (7 Replies)
dear sir,
pls. can you help me ? , my os is unix sco 5.0.4 and ,server dat derive (1,4gb)
not working, now i want to transfer my server data in other machine (unix/other possible) by serial port/other port comminication.
thanks
pankaj raval (2 Replies)
Hi All,
I am a begineer in Linux, I have 4 ports and 3 are operational port 1,port 2 and port 4 (when I plug in serial device I can see it working) but port 3 seems it is not working.
I am sure the hardware is fine.
when I give command
dmesg | grep tty
I get,
serial 8250:ttyS0 at... (0 Replies)