| /**************************************************************************** |
| * apps/examples/rfid_readuid/rfid_readuid.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 <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 |
| ****************************************************************************/ |
| |
| int main(int argc, FAR char *argv[]) |
| { |
| 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; |
| } |