mbed_wait_api_rtos.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 
00017 // This implementation of the wait functions will be compiled only
00018 // if the RTOS is present.
00019 #ifdef MBED_CONF_RTOS_PRESENT
00020 
00021 #include "platform/mbed_wait_api.h"
00022 #include "hal/us_ticker_api.h"
00023 #include "rtos/rtos.h"
00024 #include "platform/mbed_critical.h"
00025 #include "platform/mbed_power_mgmt.h"
00026 
00027 void wait(float s)
00028 {
00029     wait_us(s * 1000000.0f);
00030 }
00031 
00032 void wait_ms(int ms)
00033 {
00034     wait_us(ms * 1000);
00035 }
00036 
00037 void wait_us(int us)
00038 {
00039     const ticker_data_t *const ticker = get_us_ticker_data();
00040 
00041     uint32_t start = ticker_read(ticker);
00042     if ((us >= 1000) && core_util_are_interrupts_enabled()) {
00043         // Use the RTOS to wait for millisecond delays if possible
00044         sleep_manager_lock_deep_sleep();
00045         Thread::wait((uint32_t)us / 1000);
00046         sleep_manager_unlock_deep_sleep();
00047     }
00048     // Use busy waiting for sub-millisecond delays, or for the whole
00049     // interval if interrupts are not enabled
00050     while ((ticker_read(ticker) - start) < (uint32_t)us);
00051 }
00052 
00053 #endif // #if MBED_CONF_RTOS_PRESENT
00054