Diff: main.cpp

Revision:

0:ec9669ff706c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Jun 09 21:12:22 2014 +0000
@@ -0,0 +1,244 @@
+/****************************************************************************************/
+/*                               INTERNET OF THINGS ASSIGNMENT 6                        */
+/*This assignment implements a thermostat which turns ON/OFF depending on the set and   */
+/*current temperature. The thermostat can be turned ON/OFF by following ways:           */
+/*                    1. Joustick up button on the application board.                   */
+/*                    2. Depending on if there is movement or not                       */
+/*                    3. Remotely through wifly(Telnet)                                 */
+/****************************************************************************************/
+
+#include "mbed.h"
+#include "rtos.h"
+#include "C12832_lcd.h"
+#include "NTPClient.h"
+#include "WiflyInterface.h"
+#include "LM75B.h"
+#include "DebouncedIn.h"
+#include "MMA7660.h"
+
+#define SEC 1000                     //macro for no. of msec in sec
+#define MIN 60*SEC                  //macro for no. of msec in min
+#define hys 3
+#define TIME 20                    //Time after which system should turn OFF if
+                                   //no movement detected
+#define ECHO_SERVER_PORT   7       //Server port for HTTP client.
+
+Mutex LCD;
+C12832_LCD lcd;
+Serial pc (USBTX,USBRX);
+LM75B current(p28,p27);
+MMA7660 MMA(p28,p27);
+BusOut move(p23,p24,p25);
+
+//System ON/OFF
+BusIn heat_on (p16,p13); 
+                                      
+//Increase Temperature
+DebouncedIn temp_up (p15); 
+
+//Decrease Temperature                                    
+DebouncedIn temp_down (p12);                                   
+
+//System ON/OFF LED
+DigitalOut thermostat (LED1);
+
+//Heater ON/OFF LED. This can be furthur connected to the relay                                  
+DigitalOut heater (LED2);                                  
+
+
+int temp = 10;
+bool status = 0;
+
+void update_lcd(void const *args);       //Thread 1
+void Thermostat_logic (void const *args);      //Thread 2
+void check_movement(void const *args);      //Thread 3
+
+bool no_move;
+float acc_x = MMA.x();
+float acc_y = MMA.y();
+float acc_z = MMA.z();
+float acc_x_old,acc_y_old,acc_z_old;
+bool wifly_on = 0;
+
+WiflyInterface wifly(p9, p10, p30, p29, "MY_WIFI", "", NONE);
+
+/****************************************************************************************/
+/*Thread update_lcd: This thread is used to update the lcd. The LCD will dispaly current*/
+/*time, Set temperature and the actual temperature. If the system is OFF lcd will show  */
+/*current time and message 'System OFF'                                                 */
+/****************************************************************************************/
+void update_lcd(void const *args)
+{
+    set_time(1391739990); 
+    while (true) {
+    time_t seconds = time(NULL);
+    LCD.lock();
+    lcd.locate(0,0);
+    lcd.printf("%s",ctime(&seconds));
+    lcd.locate(0,10);
+    if (status) {                                          
+            lcd.printf("Current: %.2f",current.read());
+            lcd.locate(1,20);
+            lcd.printf("Set: %d",temp);
+        } else {                                               
+            lcd.printf("System OFF");
+        }     
+    LCD.unlock();
+    Thread::wait(200);        //LCD will update after every 200msec.
+    }
+}
+/****************************************************************************************/
+
+/****************************************************************************************/
+/*Thread: thermostat logic: This thread implements the logic of the thermostat. It turns*/
+/*ON/OFF the thermostat depending on temperature, movement and the web control. It also */
+/*allows the user to set the temperature from the push button switches. The setting of  */
+/*temperature can also be done remotely through xively. Currently the program just      */
+/*controls turning ON/OFF the system remotely.                                          */
+/****************************************************************************************/
+void Thermostat_logic(void const *args)
+{
+    while (true) {
+        if (heat_on == 0x2  || wifly_on || !no_move) 
+        {
+            thermostat = 1;                                    
+            status = 1;   
+            wifly_on = 1;                                     
+        } else if ( wifly_on == 0 ){              
+            thermostat = 0;                                    
+            heater = 0;                                       
+            status = 0;   
+            wifly_on = 0;                                    
+        }
+        else if (heat_on == 0x1 || no_move ) {                
+            thermostat = 0;                                    
+            heater = 0;                                       
+            status = 0;   
+            wifly_on = 0;                                    
+        }
+        
+        /*If the joystick is pushed upwards increase set temperature by 2
+        And print the set temperature on LCD.*/
+        if (temp_up.rising()) {                                
+            temp = temp + 0x2;                                                      
+        }
+        
+        /*else if the joystick is pushed downwards decrease set temperature by 2
+        And print the set temperature on LCD.*/ 
+        
+        else if (temp_down.rising()) {                       
+            temp = temp - 0x2;                                 
+        }
+
+        //Comparison logic and turn Heater ON/OFF
+        if ((temp > (current.read()+ hys)) && thermostat == 1)
+            heater =  1;
+        else if ((temp < (current.read()- hys)) || thermostat == 0)
+            heater = 0;
+            
+        if (acc_x_old != MMA.x() || acc_y_old != MMA.y() || acc_z_old != MMA.x())
+       {
+           no_move = 0;
+       }
+         
+        Thread::wait(100);      //Temperature comparison will take place after 
+                                      //every 100msec.
+    }
+}
+/****************************************************************************************/
+
+
+/****************************************************************************************/
+/*Thread check movement: This thread detects if there is movement nearby the thermostat.*/
+/*If there is no movement this thread sets a variable called no_move which is furthur   */
+/*used to turn ON/OFF the system. Logic implemented for movement detection is as follows*/
+/*This thread is executed once every minute. Every time this thread is executed it      */
+/*compares the accelerometer reading with its previous value. If the reading is same    */
+/*(no movement detected) it increments a counter. When this counter reaches 20 (which   */
+/*means there is no movement for 20 mins) it sets the variable no_move to turn OFF the  */
+/*system. When a different accelerometer value is detected(movement present) it resets  */
+/*the variable which will in turn turn the system ON.                                   */
+/****************************************************************************************/
+void check_movement(void const *args)
+{
+    static int move_cntr = 0;
+    while (true) {
+    acc_x_old = acc_x;
+    acc_y_old = acc_y;
+    acc_z_old = acc_z;
+    acc_x = MMA.x();
+    acc_y = MMA.y();
+    acc_z = MMA.z();
+    if (acc_x_old == acc_x && acc_y_old == acc_y && acc_z_old == acc_z)
+    {
+        move_cntr++;
+        pc.printf("Value of move_cntr = %d\r\n",move_cntr);
+        move = 011;
+    }
+    else {
+        move_cntr = 0;
+        pc.printf("Move_cntr reset\r\n");}
+    if (move_cntr >= TIME)    //If the Accelerometer value remains constant for 20 mins no movement detected
+        no_move = 1;
+    else
+        no_move = 0;
+    Thread::wait(1*MIN);
+    }
+    
+}
+/****************************************************************************************/
+
+
+/****************************************************************************************/
+/*Thread main: This is the main thread which instantiates all other threads. The main   */
+/*thread also initializes the wifly module and communicates with the mbed via wifly.    */
+/*If the HTTP client is not connected, the main thread continues its operation through  */
+/*the on board joystick. Turning ON/OFF the thermostat remotely is not possible in such */
+/*a case. The other controls like the joystick and the accelorometer operate normally.  */
+/****************************************************************************************/
+int main() {
+    
+    Thread lcd_display(update_lcd,NULL,  osPriorityAboveNormal);
+    Thread thermostat_thread(Thermostat_logic,NULL,  osPriorityAboveNormal);
+    Thread accel_thread(check_movement,NULL,osPriorityAboveNormal);
+    
+    wifly.init(); //Use DHCP
+    while (!wifly.connect());
+    pc.printf("IP Address is %s\n\r", wifly.getIPAddress());
+ 
+    TCPSocketServer server;
+    
+    server.bind(ECHO_SERVER_PORT);
+    server.listen();
+ 
+    printf("\nWait for new connection...\r\n");
+    TCPSocketConnection client;
+    server.accept(client);
+    char buffer[3];   
+    // NTPClient ntp;
+    //ntp.setTime("nist1.symmetricom.com");
+
+        while (true) {
+            if (client.is_connected()){          
+            int n = client.receive(buffer, sizeof(buffer));
+            if (n <= 0)continue; 
+            buffer[n] = 0;
+            pc.printf("Buffer is %s\r\n",buffer);
+            if (!(strcmp(buffer,"o")))
+               wifly_on = 1;
+            else if (!(strcmp(buffer,"f"))){
+               wifly_on = 0;
+               pc.printf("wifi off\r\n");
+            }
+                Thread::wait(100);
+        client.send_all(buffer,n);
+        pc.printf("Sent data is %s\r\n",buffer);
+        }
+        else
+        Thread::wait(1*SEC);
+        Thread::wait(100);   //This wait is necessary for the condition in which http
+                                     //client is connected but it does not receive anything.
+                                     //if n<= 0
+        }
+}
+/****************************************************************************************/
\ No newline at end of file