I know that there is a section at the Arduino Playground on interfacing the Arduino with C. However, I found it is much easier, almost trivial, to use libSerial with C++.
(libSerial works on POSIX systems. I guess Windows users could use it through Cygwin but I’m not sure)
(Update: No, they can’t)
First, you import your libraries and define the port you will be using:
#include < SerialStream.h >
#include < iostream >
#define PORT "/dev/ttyUSB0" //This is system-specific
SerialStream ardu;
using namespace std;
using namespace LibSerial;
The above code is assuming that the arduino is bound to /dev/ttyUSB0. Make sure to point the stream to the real device on you computer ;)
A new serial stream “ardu” is created.
Now let’s define a simple function to setup the Arduino for communication.
void open(){
/*The arduino must be setup to use the same baud rate*/
ardu.Open(PORT);
ardu.SetBaudRate(SerialStreamBuf::BAUD_9600);
ardu.SetCharSize(SerialStreamBuf::CHAR_SIZE_8);
(....)
At least in my case, this simple function is enough to have a working serial communication with the microcontroller.
Now I’ll write another simple function that sends one byte through the serial port to the arduino and then reads a string, which gets interpreted as an integer..
int get(char out){
int res;
char str[SOME_BIG_SIZE];
ardu << out;
ardu >> str;
sscanf(str,"%d",&res);
return res;
}
See? It’s easy! :)
If for some reason you must use standard POSIX libraries, here is a great article on POSIX serial programming.
If you have any doubts, post a comment.
