nuttx-apps/examples/rfid_readuid/rfid_readuid.c
2016-10-06 07:46:01 -06:00

120 lines
3.8 KiB
C

/****************************************************************************
* examples/rfid_readuid/rfid_readuid.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Alan Carvalho de Assis <acassis@gmail.com>
*
* 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 <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <nuttx/contactless/mfrc522.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef CONFIG_CL_MFRC522
# error "CONFIG_CL_MFRC522 is not defined in the configuration"
#endif
#ifndef CONFIG_EXAMPLES_RFID_READUID_DEVNAME
# define CONFIG_EXAMPLES_RFID_READUID_DEVNAME "/dev/rfid0"
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* rfid_readuid_main
****************************************************************************/
#ifdef CONFIG_BUILD_KERNEL
int main(int argc, FAR char *argv[])
#else
int rfid_readuid_main(int argc, char *argv[])
#endif
{
int fd;
int ret;
int count = 0;
char buffer[10];
fd = open(CONFIG_EXAMPLES_RFID_READUID_DEVNAME, O_RDONLY);
if (fd < 0)
{
printf("Failed to open %s\n", CONFIG_EXAMPLES_RFID_READUID_DEVNAME);
return -1;
}
/* Try to read a card up to 3 times */
while (count < 3)
{
printf("Trying to READ: ");
/* 11 bytes = 0x12345678\0 */
ret = read(fd, buffer, 11);
if (ret == 11)
{
printf("RFID CARD UID = %s\n", buffer);
break;
}
if (ret == -EAGAIN || ret == -EPERM)
{
printf("Card is not present!\n");
}
else
{
printf("Unknown error!\n");
}
/* Wait 500ms before trying again */
usleep(500000);
count++;
}
return 0;
}