Timer.h

00001 /* mbed Microcontroller Library - Timer
00002  * Copyright (c) 2007-2009 ARM Limited. All rights reserved.
00003  */ 
00004  
00005 #ifndef MBED_TIMER_H
00006 #define MBED_TIMER_H
00007 
00008 #include "platform.h"
00009 #include "PinNames.h"
00010 #include "PeripheralNames.h"
00011 #include "Base.h"
00012 
00013 namespace mbed {
00014 
00015 /** A general purpose timer 
00016  *
00017  * Example:
00018  * @code
00019  * // Count the time to toggle a LED
00020  *
00021  * #include "mbed.h"
00022  * 
00023  * Timer timer;
00024  * DigitalOut led(LED1);
00025  * int begin, end;
00026  * 
00027  * int main() {
00028  *     timer.start();
00029  *     begin = timer.read_us();
00030  *     led = !led;
00031  *     end = timer.read_us();
00032  *     printf("Toggle the led takes %d us", end - begin);
00033  * }
00034  * @endcode
00035  */
00036 class Timer : public Base {
00037 
00038 public:
00039 
00040     Timer(const char *name = NULL);
00041     
00042     /** Start the timer
00043      */
00044     void start(); 
00045 
00046     /** Stop the timer
00047      */
00048     void stop(); 
00049 
00050     /** Reset the timer to 0. 
00051      *
00052      * If it was already counting, it will continue
00053      */
00054     void reset();
00055 
00056     /** Get the time passed in seconds
00057      */
00058     float read();
00059 
00060     /** Get the time passed in mili-seconds
00061      */
00062     int read_ms();
00063 
00064     /** Get the time passed in micro-seconds
00065      */
00066     int read_us();
00067 
00068 #ifdef MBED_OPERATORS 
00069     operator float();
00070 #endif
00071 
00072 #ifdef MBED_RPC
00073     virtual const struct rpc_method *get_rpc_methods();
00074     static struct rpc_class *get_rpc_class();
00075 #endif
00076 
00077 protected:
00078 
00079     int slicetime();    
00080     int _running;          // whether the timer is running
00081     unsigned int _start;   // the start time of the latest slice
00082     int _time;             // any accumulated time from previous slices
00083     
00084 };
00085 
00086 } // namespace mbed
00087 
00088 #endif
00089