/****************************************************************************
* examples/timer/timer_main.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <nuttx/timer.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef CONFIG_EXAMPLE_TIMER_DEVNAME
# define CONFIG_EXAMPLE_TIMER_DEVNAME "/dev/timer0"
#endif
#ifndef CONFIG_EXAMPLE_TIMER_INTERVAL
# define CONFIG_EXAMPLE_TIMER_INTERVAL 1000000
#endif
#ifndef CONFIG_EXAMPLE_TIMER_DELAY
# define CONFIG_EXAMPLE_TIMER_DELAY 100000
#endif
#ifndef CONFIG_EXAMPLE_TIMER_NSAMPLES
# define CONFIG_EXAMPLE_TIMER_NSAMPLES 20
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* timer_handler
****************************************************************************/
static bool timer_handler(FAR uint32_t *next_interval_us)
{
/* This handler may:
*
* (1) Modify the timeout value to change the frequency dynamically, or
* (2) Return false to stop the timer.
*/
return true;
}
/****************************************************************************
* timer_status
****************************************************************************/
static void timer_status(int fd)
{
struct timer_status_s status;
int ret;
/* Get timer status */
ret = ioctl(fd, TCIOC_GETSTATUS, (unsigned long)((uintptr_t)&status));
if (ret < 0)
{
fprintf(stderr, "ERROR: Failed to get timer status: %d\n", errno);
close(fd);
exit(EXIT_FAILURE);
}
/* Print the timer status */
printf(" flags: %08lx timeout: %lu timeleft: %lu\n",
(unsigned long)status.flags, (unsigned long)status.timeout,
(unsigned long)status.timeleft);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* timer_main
****************************************************************************/
#ifdef CONFIG_BUILD_KERNEL
int main(int argc, FAR char *argv[])
#else
int timer_main(int argc, char *argv[])
#endif
{
struct timer_sethandler_s handler;
int ret;
int fd;
int i;
/* Open the timer device */
printf("Open %s\n", CONFIG_EXAMPLE_TIMER_DEVNAME);
fd = open(CONFIG_EXAMPLE_TIMER_DEVNAME, O_RDONLY);
if (fd < 0)
{
fprintf(stderr, "ERROR: Failed to open %s: %d\n",
CONFIG_EXAMPLE_TIMER_DEVNAME, errno);
return EXIT_FAILURE;
}
/* Show the timer status before setting the timer interval */
timer_status(fd);
/* Set the timer interval */
printf("Set timer interval to %lu\n",
(unsigned long)CONFIG_EXAMPLE_TIMER_INTERVAL);
ret = ioctl(fd, TCIOC_SETTIMEOUT, CONFIG_EXAMPLE_TIMER_INTERVAL);
if (ret < 0)
{
fprintf(stderr, "ERROR: Failed to set the timer interval: %d\n", errno);
close(fd);
return EXIT_FAILURE;
}
/* Show the timer status before attaching the timer handler */
timer_status(fd);
/* Attach the timer handler
*
* NOTE: If no handler is attached, the timer stop at the first interrupt.
*/
printf("Attach timer handler\n");
handler.newhandler = timer_handler;
handler.oldhandler = NULL;
ret = ioctl(fd, TCIOC_SETHANDLER, (unsigned long)((uintptr_t)&handler));
if (ret < 0)
{
fprintf(stderr, "ERROR: Failed to set the timer handler: %d\n", errno);
close(fd);
return EXIT_FAILURE;
}
/* Show the timer status before starting */
timer_status(fd);
/* Start the timer */
printf("Start the timer\n");
ret = ioctl(fd, TCIOC_START, 0);
if (ret < 0)
{
fprintf(stderr, "ERROR: Failed to start the timer: %d\n", errno);
close(fd);
return EXIT_FAILURE;
}
/* Wait a bit showing timer status */
for (i = 0; i < CONFIG_EXAMPLE_TIMER_NSAMPLES; i++)
{
usleep(CONFIG_EXAMPLE_TIMER_DELAY);
timer_status(fd);
}
/* Stop the timer */
printf("Stop the timer\n");
ret = ioctl(fd, TCIOC_STOP, 0);
if (ret < 0)
{
fprintf(stderr, "ERROR: Failed to stop the timer: %d\n", errno);
close(fd);
return EXIT_FAILURE;
}
/* Show the timer status before starting */
timer_status(fd);
/* Close the timer driver */
printf("Finished\n");
close(fd);
return EXIT_SUCCESS;
}
