tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F3/us_ticker.c

   1 /* mbed Microcontroller Library
   2  * Copyright (c) 2014, STMicroelectronics
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright notice,
   9  *    this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright notice,
  11  *    this list of conditions and the following disclaimer in the documentation
  12  *    and/or other materials provided with the distribution.
  13  * 3. Neither the name of STMicroelectronics nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  18  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28 #include <stddef.h>
  29 #include "us_ticker_api.h"
  30 #include "PeripheralNames.h"
  31
  32 // 32-bit timer selection
  33 #define TIM_MST      TIM2
  34
  35 static TIM_HandleTypeDef TimMasterHandle;
  36 static int us_ticker_inited = 0;
  37
  38 void us_ticker_init(void)
  39 {
  40     if (us_ticker_inited) return;
  41     us_ticker_inited = 1;
  42
  43     TimMasterHandle.Instance = TIM_MST;
  44
  45     HAL_InitTick(0); // The passed value is not used
  46 }
  47
  48 uint32_t us_ticker_read()
  49 {
  50     if (!us_ticker_inited) us_ticker_init();
  51     return TIM_MST->CNT;
  52 }
  53
  54 void us_ticker_set_interrupt(timestamp_t timestamp)
  55 {
  56     // Set new output compare value
  57     __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_1, (uint32_t)timestamp);
  58     // Enable IT
  59     __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC1);
  60 }
  61
  62 void us_ticker_disable_interrupt(void)
  63 {
  64     __HAL_TIM_DISABLE_IT(&TimMasterHandle, TIM_IT_CC1);
  65 }
  66
  67 void us_ticker_clear_interrupt(void)
  68 {
  69     __HAL_TIM_CLEAR_IT(&TimMasterHandle, TIM_IT_CC1);
  70 }