main.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2018-2018 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #include "events/EventQueue.h"
00018 
00019 #include "nfc/ndef/MessageBuilder.h"
00020 #include "nfc/ndef/common/URI.h"
00021 #include "nfc/ndef/common/util.h"
00022 
00023 #include "NFCEEPROM.h"
00024 
00025 #include "EEPROMDriver.h"
00026 #include <cstdio>
00027 
00028 using events::EventQueue;
00029 
00030 using mbed::nfc::NFCEEPROM;
00031 using mbed::nfc::NFCEEPROMDriver;
00032 using mbed::Span;
00033 
00034 using mbed::nfc::ndef::MessageBuilder;
00035 using mbed::nfc::ndef::common::URI;
00036 using mbed::nfc::ndef::common::span_from_cstr;
00037 
00038 /* URL that will be written into the tag */
00039 const char url_string[] = "st.com";
00040 
00041 class EEPROMExample : mbed::nfc::NFCEEPROM::Delegate
00042 {
00043 public:
00044     EEPROMExample(events::EventQueue& queue, NFCEEPROMDriver& eeprom_driver) :
00045         _ndef_buffer(),
00046         _eeprom(&eeprom_driver, &queue, _ndef_buffer),
00047         _queue(queue)
00048     { }
00049 
00050     void run()
00051     {
00052         if (_eeprom.initialize() != NFC_OK) {
00053             printf("failed to initialise\r\n");
00054             _queue.break_dispatch();
00055         }
00056 
00057         _eeprom.set_delegate(this);
00058 
00059         _queue.call(&_eeprom, &NFCEEPROM::write_ndef_message);
00060     }
00061 
00062 private:
00063     virtual void on_ndef_message_written(nfc_err_t result) {
00064         if (result == NFC_OK) {
00065             printf("message written successfully\r\n");
00066         } else {
00067             printf("failed to write (error: %d)\r\n", result);
00068         }
00069 
00070         _queue.call(&_eeprom, &NFCEEPROM::read_ndef_message);
00071     }
00072 
00073     virtual void on_ndef_message_read(nfc_err_t result) {
00074         if (result == NFC_OK) {
00075             printf("message read successfully\r\n");
00076         } else {
00077             printf("failed to read (error: %d)\r\n", result);
00078         }
00079     }
00080 
00081     virtual void parse_ndef_message(const Span<const uint8_t> &buffer) {
00082         printf("Received an ndef message of size %d\r\n", buffer.size());
00083     }
00084 
00085     virtual size_t build_ndef_message(const Span<uint8_t> &buffer) {
00086         printf("Building an ndef message\r\n");
00087 
00088         /* create a message containing the URL */
00089 
00090         MessageBuilder builder(buffer);
00091 
00092         /* URI expected a non-null terminated string  so we use a helper function that casts
00093          * the pointer into a Span of size smaller by one */
00094         URI uri(URI::HTTPS_WWW, span_from_cstr(url_string));
00095 
00096         uri.append_as_record(builder, true);
00097 
00098         return builder.get_message().size();
00099     }
00100 
00101 private:
00102     uint8_t _ndef_buffer[1024];
00103     NFCEEPROM _eeprom;
00104     EventQueue& _queue;
00105 };
00106 
00107 int main()
00108 {
00109     EventQueue queue;
00110     NFCEEPROMDriver& eeprom_driver = get_eeprom_driver(queue);
00111 
00112     EEPROMExample example(queue, eeprom_driver);
00113 
00114     example.run();
00115     queue.dispatch_forever();
00116 
00117     return 0;
00118 }
00119