serial port programming in c

[j1s]

Hi.

I'm just learning the c language, and I've read lots and lots of google search and forum listings. But I can not find what I need.

I want to control one simple LED with the serialport. I want to set the time the led will light.

Does anyone know how to do this? Or know the url to a good tutorial?

j1s

[GNU-Fan]

Serial HOWTO

[j1s]

Thanks but - Been there, done that...

[GNU-Fan]

With the text at hand being read and understood by you, I can't see what step you have trouble with.

[j1s]

The first time I read it, it seemed understandable, but it didn't get to me.

I will now concentrate, and read it again.

Thanks for your time!

Appreciate it!!

[curi]

Maybe you could try these examples; they explain how to work with functions like open(), read(), write() and close().
For example, if you want to use the serial port device ttyS0, you have to do
.
.
.
serial_fd = open ("/dev/ttyS0",B9600);//9600 bauds

if (serial_fd==-1) {
printf ("Error opening the serial device: "/dev/ttyS0");
perror("OPEN");
exit(0);
}


//Now the port is ready to work
//Write anything you want to the port;
//It`s stored in buf

write (serial_fd, &buf, buf_size);
printf ("String sent------> %s\n",buf);

//We can read from port too, this is the way
n=read(serial_fd,data,buf_size);
.
.
//Finally, you close the port
close(serial_fd);

Pay attention that you have to configure the serial port with settings that you'll find in header file "termios.h"

I hope that's helpful.

[j1s]

Thank you, curi.

This was most helpful, and explained in a simple way.

Thanks for your time and effort!