main.cpp

00001 #include "mbed.h"
00002 #include <cctype>
00003 #include "Car.h"
00004 #include "TextLCD.h"
00005 #include "signal_wrapper.h"
00006 
00007 Serial pc(USBTX, USBRX);    // The connection to USB
00008 TextLCD lcd(p15, p16, p17, p18, p19, p20, TextLCD::LCD16x2 ); // rs, e, d4-d7
00009 
00010 // define any needed global variables
00011 // ...
00012 // ...
00013 #define MAX_CAR_SPEED 15
00014 #define MIN_CAR_SPEED 5
00015 
00016 // This function present the "prompt" string to the user before accepting
00017 // an integer back from the Serial connection. If the user enters anything
00018 // other than a digit (e.g. return key, letters), the currently built number
00019 // is returned
00020 int read_int(char* prompt) {
00021     int number = 0;
00022     
00023     pc.printf(prompt);
00024     
00025     char input;
00026     while(1) {
00027         input = pc.getc();
00028         pc.putc(input);
00029         
00030         if( std::isdigit(input) ) {
00031             number = (number * 10) + (input-'0');   
00032         } else {
00033             pc.putc(input);
00034             break;   
00035         } 
00036     }
00037     
00038     return number;
00039 }
00040 
00041 void handle_input(int* car_speed)
00042 {
00043     int valid_reading = 0;
00044     while( !valid_reading )
00045     {
00046         *car_speed = read_int("car_speed:");   
00047         if( *car_speed >= MIN_CAR_SPEED && *car_speed <= MAX_CAR_SPEED )
00048         {
00049             valid_reading = 1;
00050             printf("\r\n");
00051         }
00052         else
00053         {
00054             printf("\r\n");
00055             printf("invalid input ... range: %d -> %d\r\n", MIN_CAR_SPEED, MAX_CAR_SPEED);
00056         }
00057             
00058     }
00059 }
00060 
00061 // The main thread of the program. This runs the main program, accepting user
00062 // input, creating cars, displaying state of cars, and handling coordination that
00063 // may be needed. Timing statistics are also presented.
00064 int main()
00065 {   
00066     // ------------------------------------------------------------------------------
00067     // The following three variables are used for timing statistics, do not modify them
00068     Timer stopwatch;    // A timer to keep track of how long the updates take, for statistics purposes
00069     int numberCycles = 0;
00070     int totalUpdateTime = 0;
00071     // ------------------------------------------------------------------------------
00072     // prepare screen for input
00073     printf("\033[2J");
00074     printf("\r\n");
00075     
00076     
00077     
00078     Car car(0);         // Create a car. This call will need to be modified with any additional parameters you add
00079     stopwatch.start();  // Start out stats timer
00080     
00081     while (true) {      // Run the simulation indefinitely
00082         
00083         int carspeed =0;
00084         // Prompt the user for an initial speed and ensure it is valid
00085         handle_input(&carspeed);
00086         // Start the car / let the car know its initial speed
00087         car.reset(carspeed);
00088         lcd.cls();
00089         // ----------------------------------------------------------------------
00090         // Timing statistics logic, do not modify
00091         stopwatch.reset();
00092         // ----------------------------------------------------------------------
00093         
00094         do {    // Run the simulation until the car exits the road
00095 ;
00096             // wait some time before sending signal
00097             while(stopwatch.read_ms() < TICK)
00098             {
00099                 // do nothing I guess
00100             }
00101             
00102             //signal car it can update
00103             send_signal( CAR_SIGNAL );
00104             
00105             // wait for car to update
00106             wait_for_signal( CAR_UPDATE_MAIN_SIGNAL );
00107 
00108             // ------------------------------------------------------------------
00109             // Timing statistics logic, do not modify
00110             totalUpdateTime += stopwatch.read_ms();
00111             numberCycles++;
00112             stopwatch.reset();
00113             // ------------------------------------------------------------------
00114             lcd.cls();
00115             // Display the state of the car to the LCD
00116             lcd.printf( "%d -> %d \n",car.speed,car.position );
00117             
00118         } while (car.is_simulating());     // Modify this condition to stop the simulation when the car exits the road
00119         // ----------------------------------------------------------------------
00120         // Timing statistics printout, do not modify
00121         pc.printf("Resetting...\r\n");
00122         pc.printf("Average update cycle took: %fms \r\n", (totalUpdateTime*1.0)/(numberCycles*1.0));
00123         totalUpdateTime = 0;
00124         numberCycles = 0;
00125         // ----------------------------------------------------------------------
00126     }
00127 }