tmk_core/tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32L1/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 #define TIM_MST TIM5
  33
  34 static TIM_HandleTypeDef TimMasterHandle;
  35 static int us_ticker_inited = 0;
  36
  37 void us_ticker_init(void)
  38 {
  39     if (us_ticker_inited) return;
  40     us_ticker_inited = 1;
  41
  42     TimMasterHandle.Instance = TIM_MST;
  43
  44     HAL_InitTick(0); // The passed value is not used
  45 }
  46
  47 uint32_t us_ticker_read()
  48 {
  49     if (!us_ticker_inited) us_ticker_init();
  50     return TIM_MST->CNT;
  51 }
  52
  53 void us_ticker_set_interrupt(timestamp_t timestamp)
  54 {
  55     // Set new output compare value
  56     __HAL_TIM_SetCompare(&TimMasterHandle, TIM_CHANNEL_1, (uint32_t)timestamp);
  57     // Enable IT
  58     __HAL_TIM_ENABLE_IT(&TimMasterHandle, TIM_IT_CC1);
  59 }
  60
  61 void us_ticker_disable_interrupt(void)
  62 {
  63     __HAL_TIM_DISABLE_IT(&TimMasterHandle, TIM_IT_CC1);
  64 }
  65
  66 void us_ticker_clear_interrupt(void)
  67 {
  68     __HAL_TIM_CLEAR_IT(&TimMasterHandle, TIM_IT_CC1);
  69 }