main.cpp

00001 /**
00002  * Door lock Mechanism which work similar to locking and unlocking
00003  * by using an RFID card to scan nfc tag which is publish onto MQTT
00004  * server by saying in door is locked or unlucked.
00005  * By Kwame Nyantakyi
00006 
00007  * Use of MQTT client code created by Daniel Knox and Fred Barnes
00008 **/
00009 
00010 //
00011 #include "mbed.h"
00012 #include "C12832.h"
00013 #include "MQTTEthernet.h"
00014 #include "MQTTClient.h"
00015 
00016 /* speed we talk up the [USB] serial-port at */
00017 #define HOST_SPEED (38400)
00018 
00019 // Using Arduino pin notation
00020 C12832 lcd(D11, D13, D12, D7, D10);
00021 
00022 static Serial host (USBTX, USBRX);      /* connection to host */
00023 
00024 // led display
00025 DigitalOut red_led(D5);
00026 DigitalOut green_led(D9);
00027 
00028 // joystick left and right
00029 DigitalIn left(A4);
00030 AnalogIn right(A5);
00031 
00032 // sw2 and sw3
00033 InterruptIn sw2_int (PTC6);             /* interrupts for the two on-board switches */
00034 InterruptIn sw3_int (PTA4);
00035 
00036 static volatile int sw2_trig;           /* switches triggered? */
00037 static volatile int sw3_trig;
00038 
00039 PwmOut spkr(D6);
00040 
00041 const char* def  = "Unknown";
00042 const char* stat  = "Unknown";
00043 
00044 
00045 /* connection stuff for MQTT */
00046 typedef struct S_mqtt_params {
00047     char *hostname;
00048     int port;
00049     char *topic;
00050     char *clientid;
00051 } mqtt_params_t;
00052 
00053 /* configure MQTT with hostname, port, topic and clientid */
00054 static mqtt_params_t mqtt_config = {
00055 hostname: "129.12.44.120"
00056     ,
00057     port: 1883,
00058 topic: "unikent/users/kn241/room/status"
00059     ,
00060 clientid: "kn241"
00061 };
00062 
00063 /*
00064 * prints stuffs on the serial host and lcd
00065 */
00066 static int set_up(void)
00067 {
00068     host.baud (HOST_SPEED);
00069     host.printf ("\r\n\r\nEthernet MQTT client from K64F\r\n");
00070 
00071     lcd.cls ();
00072     lcd.locate (0, 0);
00073     lcd.printf ("Door Lock Mechanism\n");
00074 
00075     return 0;
00076 }
00077 
00078 
00079 /*
00080 * Display the status of the connection to MQTT aswell as
00081 * the activity of the user.
00082 *
00083 * Roboust function used to print out format,arg of server
00084 * server connection and user interaction on the serial host
00085 * and lcd
00086 */
00087 static int display_info(const char *format, ...)
00088 {
00089     va_list arg;
00090     int re;
00091 
00092     va_start(arg, format);
00093     re = host.vprintf (format, arg);
00094     va_end (arg);
00095     host.printf ("\r\n");
00096 
00097     lcd.fill (0, 20, 128, 12, 0);
00098     lcd.locate (0, 15);
00099     va_start (arg, format);
00100     lcd.vprintf (format, arg);
00101     va_end (arg);
00102 
00103     return re;
00104 }
00105 
00106 /* plays sounds and sets chars to accepted */
00107 void accepted()
00108 {
00109     def = "Accepted";
00110     stat= "Unlocked";
00111     for (float i=2000.0f; i<10000.0f; i+=100) {
00112         spkr.period(1.0f/i);
00113         spkr=0.5;
00114         wait(0.02);
00115         spkr = 0.0;
00116     }
00117 }
00118 
00119 /* function which checks  when wrong card is scanned */
00120 void declined()
00121 {
00122     def = "Rejected";
00123     stat ="Locked";
00124     red_led = !left;
00125 
00126     for (float i=2000.0f; i<10000.0f; i+=100) {
00127         spkr.period(1.0/150.0); // 500hz period
00128         spkr =0.25;
00129         wait(.02);
00130         spkr=0.0;
00131     }
00132 }
00133 
00134 //main code, where the program runs
00135 int main()
00136 {
00137     const char *ip;
00138     int re = 0;
00139     MQTT::Message msg;
00140     char buf[200];
00141 
00142     set_up();
00143     display_info("Establishing network...");
00144 
00145     /* Brings up the network interface */
00146     MQTTEthernet eth = MQTTEthernet ();
00147     ip = eth.get_ip_address();
00148 
00149     display_info("IP address is: %s", ip ?: "Not found.");
00150 
00151     /* Create Mbed Client Interface */
00152     MQTT::Client<MQTTEthernet, Countdown> client = MQTT::Client<MQTTEthernet, Countdown> (eth);
00153 
00154     /* Create TCP connection */
00155     eth.open (eth.getEth());
00156     re = eth.connect (mqtt_config.hostname, mqtt_config.port);
00157 
00158 
00159     if (!re) {
00160         display_info ("Connected Status: Good");
00161 
00162         /* Wait for a short length of time to allow user to see output messages. */
00163         Thread::wait(1500);
00164 
00165         MQTTPacket_connectData data = MQTTPacket_connectData_initializer;
00166         data.keepAliveInterval = 20;
00167         data.cleansession = 1;
00168         data.MQTTVersion = 3;
00169         data.clientID.cstring = mqtt_config.clientid;
00170         re = client.connect (data);
00171 
00172         if (!re) {
00173             display_info ("MQTT connected!");
00174 
00175             while (!re) {
00176                 /* clear screen to setup - set up door status*/
00177                 lcd.cls ();
00178                 set_up();
00179 
00180                 while(1) {
00181 
00182                     //Depending on button pressed display a colour
00183                     red_led = !left;
00184                     green_led = !right;
00185 
00186                     if(right && !left) {
00187                         accepted();
00188                     } else if(left && !right) {
00189                         declined();
00190                     }
00191                     display_info("Scan :%s \n", def);
00192                     sprintf (buf, "%s\n", stat);
00193                     // QoS 0
00194 
00195                     msg.qos = MQTT::QOS0;
00196                     msg.retained = false;
00197                     msg.dup = false;
00198                     msg.payload = (void*)buf;
00199                     msg.payloadlen = strlen(buf)+1;
00200 
00201                     re = client.publish (mqtt_config.topic, msg);
00202                     wait(1.0);
00203 
00204 
00205                     if (re) {
00206                         //if data can't be publish
00207                         display_info ("MQTT publish failed with %d", re);
00208                     } else {
00209                         Thread::wait(1500);
00210                     }
00211                 }
00212             }
00213         } else {
00214             //
00215             display_info ("Failed to connect to MQTT");
00216         }
00217     } else {
00218         display_info ("Failed to connect (TCP)");
00219     }
00220 
00221     // closed ethernet socket
00222     eth.disconnect();
00223 }