Hi David,
The code i previosuly sent you is the way I expect to use it, because for my purposes I dont need to know the current position of the servo so i just took the get position function out and set a default value of the position variable. One piece of information I forgot to give you was i am connecting the servo controller to the ITX using a mini USB, does that affect anything? I have posted below the actual code im using and also the output of ttyACM0. Thanks in advance.
Output of ttyACM0:
ls /dev/ttyACM*
output: /dev/ttyACM0 /dev/ttyACM1
My code that i am using is below:
// Uses POSIX functions to send and receive data from a Maestro.
// NOTE: The Maestro’s serial mode must be set to “USB Dual Port”.
// NOTE: You must change the ‘const char * device’ line below.
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#ifdef _WIN32
#define O_NOCTTY 0
#else
#include <termios.h>
#endif
// Sets the target of a Maestro channel.
// See the “Serial Servo Commands” section of the user’s guide.
// The units of ‘target’ are quarter-microseconds.
int maestroSetTarget(int fd, unsigned char channel, unsigned short target)
{
unsigned char command[] = {0x84, channel, target & 0x7F, target >> 7 & 0x7F};
if (write(fd, command, sizeof(command)) == -1)
{
perror(“error writing”);
return -1;
}
return 0;
}
int main()
{
// Open the Maestro’s virtual COM port.
const char * device = “\\.\USBSER000”; // Windows, “\\.\COM6” also works
//const char * device = “/dev/ttyACM0”; // Linux
//const char * device = “/dev/cu.usbmodem00034567”; // Mac OS X
int fd = open(device, O_RDWR | O_NOCTTY);
if (fd == -1)
{
perror(device);
return 1;
}
#ifndef _WIN32
struct termios options;
tcgetattr(fd, &options);
options.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
options.c_oflag &= ~(ONLCR | OCRNL);
tcsetattr(fd, TCSANOW, &options);
#endif
int position = 1500;
printf(“Current position is %d.\n”, position);
int target = (position < 6000) ? 7000 : 5000;
printf(“Setting target to %d (%d us).\n”, target, target/4);
maestroSetTarget(fd, 0, target);
close(fd);
return 0;
}
