Read data from serial port on thread


At first - sorry for my english

I need to read data from serial port (from GPS reciever)
I wrote a small app using SerialPort X2. It works.
But. I read data every 1 sec (on timer fire). And the recieving data is not very well. it could be without some first bytes or last bytes. So I need to read data from the “thread” (I did it when I wrote using Delphi in Windows).
I know that it could be using ObjC, but I am quit newbie in C

If someone have a small example (with tons of comments) on how to do it - it will be very helpfull


xCode 4, MacOSX 10.6