main.cpp

00001 /*
00002 The MIT License (MIT)
00003 
00004 Copyright (c) 2016 British Broadcasting Corporation.
00005 This software is provided by Lancaster University by arrangement with the BBC.
00006 
00007 Permission is hereby granted, free of charge, to any person obtaining a
00008 copy of this software and associated documentation files (the "Software"),
00009 to deal in the Software without restriction, including without limitation
00010 the rights to use, copy, modify, merge, publish, distribute, sublicense,
00011 and/or sell copies of the Software, and to permit persons to whom the
00012 Software is furnished to do so, subject to the following conditions:
00013 
00014 The above copyright notice and this permission notice shall be included in
00015 all copies or substantial portions of the Software.
00016 
00017 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00018 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00019 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
00020 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00021 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
00022 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
00023 DEALINGS IN THE SOFTWARE.
00024 */
00025 
00026 
00027 /*
00028  * This is a simple example that uses the micro:bit radio to show if another
00029  * micro:bit running the same code is nearby.
00030  *
00031  * Each micro:bit is periodically broadcasting a group name, and listening
00032  * to see if another micro:bit in that group is also in-range. 
00033  *
00034  * When another micro:bit in the same group is detected, the display of the
00035  * detecting micro:bit will show a filled-in heart shape
00036  *
00037  * Otherwise, the display will show an empty heart shape
00038  *
00039  */
00040 
00041 #include "MicroBit.h"
00042 
00043 #if MICROBIT_BLE_ENABLED 
00044  #ifdef YOTTA_CFG
00045   #error "This example needs BLE to be disabled. Use the yotta config.json in the proximit-heart directory to do this"
00046  #else
00047   #error "This example needs BLE to be disabled in the microbit config file in the microbit-dal: MicroBitConfig.h"
00048  #endif
00049 #endif
00050 
00051 MicroBit    uBit;
00052 
00053 // Have we seen a friend recently?
00054 uint8_t friend_seen = 0;
00055 
00056 // Are we currently sending out messages?
00057 uint8_t broadcast = 1;
00058 
00059 /* We have a group name, and if any micro:bit is in range and in the group
00060  * then the others will see it.
00061  */
00062 const char group_name[] = "tiger";
00063 
00064 const uint8_t empty_heart_arr[] {
00065                           0, 1, 0, 1, 0,
00066                           1, 0, 1, 0, 1,
00067                           1, 0, 0, 0, 1,
00068                           0, 1, 0, 1, 0,
00069                           0, 0, 1, 0, 0, };
00070 
00071 const uint8_t full_heart_arr[] {
00072                           0, 1, 0, 1, 0,
00073                           1, 1, 1, 1, 1,
00074                           1, 1, 1, 1, 1,
00075                           0, 1, 1, 1, 0,
00076                           0, 0, 1, 0, 0, }; 
00077 
00078 const uint8_t small_heart_arr[] {
00079                           0, 0, 0, 0, 0,
00080                           0, 1, 0, 1, 0,
00081                           0, 1, 1, 1, 0,
00082                           0, 1, 1, 0, 0,
00083                           0, 0, 0, 0, 0, };
00084 
00085 MicroBitImage empty_heart(5,5,empty_heart_arr);
00086 MicroBitImage full_heart(5,5,full_heart_arr);
00087 MicroBitImage small_heart(5,5,small_heart_arr);
00088 
00089 /* We send messages when people press buttons 'A' and 'B'.
00090  * At the moment, all micro:bits listening for messages
00091  * will see these and can respond to them
00092  * Challenge: make only certain micro:bits respond to these
00093  */
00094 void onButtonA(MicroBitEvent)
00095 {
00096     uBit.radio.datagram.send("1");    
00097 }
00098 
00099 void onButtonB(MicroBitEvent)
00100 {
00101     uBit.radio.datagram.send("2");    
00102 }
00103 
00104 /* We toggle broadcasting if both buttons are pressed together */
00105 void onButtonAB(MicroBitEvent)
00106 {
00107     broadcast = !broadcast;
00108     uBit.display.print("!");
00109 }
00110 
00111 
00112 void onData(MicroBitEvent)
00113 {
00114     ManagedString s = uBit.radio.datagram.recv();
00115     int rssi = uBit.radio.getRSSI();
00116 
00117     if (s == "1")
00118         uBit.display.print(full_heart);
00119 
00120     if (s == "2")
00121         uBit.display.print(small_heart);
00122     
00123     /* For detecting the presence of our friend, we require them to be sending
00124      * the same group name as we are in 
00125      */ 
00126     if (s == group_name && rssi < 70) {
00127         // We can make this larger to allow more missed packets
00128         friend_seen = 3;
00129     }
00130 }
00131 
00132 int main()
00133 {
00134     // Initialise the micro:bit runtime.
00135     uBit.init();
00136 
00137     // Setup some button handlers to allow direct heartbeat control with buttons
00138     uBit.messageBus.listen(MICROBIT_ID_BUTTON_A, MICROBIT_EVT_ANY, onButtonA);
00139     uBit.messageBus.listen(MICROBIT_ID_BUTTON_B, MICROBIT_EVT_ANY, onButtonB);
00140     uBit.messageBus.listen(MICROBIT_ID_BUTTON_AB, MICROBIT_EVT_ANY, onButtonAB);
00141 
00142     //Setup a hander to run when data is received
00143     uBit.messageBus.listen(MICROBIT_ID_RADIO, MICROBIT_RADIO_EVT_DATAGRAM, onData);
00144 
00145     uBit.radio.enable();
00146 
00147     while(1) {
00148         if (friend_seen) {
00149         uBit.display.print(full_heart); 
00150             friend_seen -= 1;
00151         } else {
00152             uBit.display.print(empty_heart);
00153         }
00154         
00155         if (broadcast)
00156             uBit.radio.datagram.send(group_name);
00157 
00158         uBit.sleep(1000);
00159     }
00160 }