C++ and Create 2

Question

I am trying to use C++ to talk to the Create 2 robot. Does anyone have basic code to write/read from the Create 2 using C++ or C?

I am having trouble with converting Create 2 commands (like 145) into one char.

Answer 1

As ott mentioned, you can simply make the type an unsigned char which is an 8 bit data type. Here is some code snipits that should work, but are untested. This uses the "Drive" example from the OI Spec.

#include <termios.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>

unsigned char buff[5] = {137, 255, 56, 1, 244};

fd = open("/dev/ttyUSB0", O_RDWR | O_NOCTTY);

struct termios tio;
bzero(&tio, sizeof(tio));
tio.c_cflag = B115200 | CS8 | CLOCAL | CREAD;
tio.c_iflag = IGNPAR;
tio.c_cc[VTIME]    = 1;
tio.c_cc[VMIN]     = 0;
tcflush(fd, TCIFLUSH);
tcsetattr(fd, TCSANOW, &tio);

int res = write(fd, buff, 5);
if (res < 0)
{
    int err = errno;
    perror("write error: ");
    printf("\nWARNING: write returned %d, errno: %d\n", res, err);
}