nuttx-apps/examples/zerocross/zerocross_main.c
Alin Jerpelea 6bc7a448de examples: author: Gregory Nutt: update licenses to Apache
Gregory Nutt is has submitted the SGA

as a result we can migrate the licenses to Apache.

Signed-off-by: Alin Jerpelea <alin.jerpelea@sony.com>
2021-06-15 05:16:58 -05:00

136 lines
3.9 KiB
C

/****************************************************************************
* examplex/zerocross/zerocross_main.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/ioctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/sensors/zerocross.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
#ifndef CONFIG_SENSORS_ZEROCROSS
# error "CONFIG_SENSORS_ZEROCROSS is not defined in the configuration"
#endif
#ifndef CONFIG_EXAMPLES_ZEROCROSS_DEVNAME
# define CONFIG_EXAMPLES_ZEROCROSS_DEVNAME "/dev/zc0"
#endif
#ifndef CONFIG_EXAMPLES_ZEROCROSS_SIGNO
# define CONFIG_EXAMPLES_ZEROCROSS_SIGNO 13
#endif
/* Helpers ******************************************************************/
#ifndef MIN
# define MIN(a,b) (a < b ? a : b)
#endif
#ifndef MAX
# define MAX(a,b) (a > b ? a : b)
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* zerocross_main
****************************************************************************/
int main(int argc, FAR char *argv[])
{
struct sigevent event;
int fd;
int tmp;
int ret;
int errcode = EXIT_FAILURE;
/* Open the zerocross device */
fd = open(CONFIG_EXAMPLES_ZEROCROSS_DEVNAME, O_RDONLY);
if (fd < 0)
{
fprintf(stderr, "ERROR: Failed to open %s: %d\n",
CONFIG_EXAMPLES_ZEROCROSS_DEVNAME, errno);
return EXIT_FAILURE;
}
/* Register to receive a signal on every zero cross event */
event.sigev_notify = SIGEV_SIGNAL;
event.sigev_signo = CONFIG_EXAMPLES_ZEROCROSS_SIGNO;
ret = ioctl(fd, ZCIOC_REGISTER, (unsigned long)((uintptr_t)&event));
if (ret < 0)
{
fprintf(stderr, "ERROR: ioctl(ZCIOC_REGISTER) failed: %d\n", errno);
goto errout_with_fd;
}
/* Ignore the default signal action */
signal(CONFIG_EXAMPLES_ZEROCROSS_SIGNO, SIG_IGN);
/* Then loop, receiving signals indicating zero cross events. */
for (; ; )
{
struct siginfo value;
sigset_t set;
ssize_t nread;
/* Wait for a signal */
sigemptyset(&set);
sigaddset(&set, CONFIG_EXAMPLES_ZEROCROSS_SIGNO);
ret = sigwaitinfo(&set, &value);
if (ret < 0)
{
fprintf(stderr, "ERROR: sigwaitinfo() failed: %d\n", errno);
goto errout_with_fd;
}
/* Show the value accompanying the signal */
printf("Signal received!\n");
printf("Sample = %d\n", value.si_value.sival_int);
}
errcode = EXIT_SUCCESS;
errout_with_fd:
close(fd);
return errcode;
}