Timer.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #include "Timer.h"
00017 #include "ticker_api.h"
00018 #include "us_ticker_api.h"
00019 
00020 namespace mbed {
00021 
00022 Timer::Timer() : _running(), _start(), _time(), _ticker_data(get_us_ticker_data()) {
00023     reset();
00024 }
00025 
00026 Timer::Timer(const ticker_data_t *data) : _running(), _start(), _time(), _ticker_data(data) {
00027     reset();
00028 }
00029 
00030 void Timer::start() {
00031     if (!_running) {
00032         _start = ticker_read(_ticker_data);
00033         _running = 1;
00034     }
00035 }
00036 
00037 void Timer::stop() {
00038     _time += slicetime();
00039     _running = 0;
00040 }
00041 
00042 int Timer::read_us() {
00043     return _time + slicetime();
00044 }
00045 
00046 float Timer::read() {
00047     return (float)read_us() / 1000000.0f;
00048 }
00049 
00050 int Timer::read_ms() {
00051     return read_us() / 1000;
00052 }
00053 
00054 int Timer::slicetime() {
00055     if (_running) {
00056         return ticker_read(_ticker_data) - _start;
00057     } else {
00058         return 0;
00059     }
00060 }
00061 
00062 void Timer::reset() {
00063     _start = ticker_read(_ticker_data);
00064     _time = 0;
00065 }
00066 
00067 #ifdef MBED_OPERATORS
00068 Timer::operator float() {
00069     return read();
00070 }
00071 #endif
00072 
00073 } // namespace mbed